The URL can be used to link to this page

Home My WebLink AboutLand Use Case.1150 River Dr.A081-02. -rlou River Drive Stream Margin Exemp~ ~2735-013-07-004 A081-02 ~3 r { 1 5661\J NED 1 1 1003 -1 i /91.-1 h 7 / 23 5 c-- 0) 3 -Â·-- 0 3 - CIL I . CASE NUMBER A081-02 PARCEL lD # 2735-013-07004 CASE NAME Joy Streambank Stabilization Project PROJECT ADDRESS 1150 River Drive PLANNER Fred Jarman CASE TYPE Stream Margin Exemption OWNER/APPLICANT William and Sarah Joy REPRESENTATIVE Beach Environmental LLC DATE OF FINAL ACTION 4/10/02 CITY COUNCIL ACTION PZ ACTION ADMIN ACTION Approved w/ Condition BOA ACTION DATE CLOSED 10/3/02 BY J. Lindt PARCEL ID: ~2735-013-07004 DATE RCVD: ~4/11/02 #COPIES:~-- CASE NO|A081-02 CASE NAME:~Joy Streambank Stabilization Project PLNR:~ Fred Jarman PROJ ADDR:~ 1150 River Drive CASE TYP:|Stream Margin Exemption STEPS1 OWN/APP: William and Sarah J ADR|1150 River Drive C/S/Z: ~Aspen/CO/81611 PHN:1 REP:1Beach Environmental LLC - ADR:J715 W. Main St., ste 3 C/S/Z:~Aspen/CO/81611 PHN~925-3475 FEESDUE1None- Fees Waived FEES RCVD~None- Fees Waived STAT: F REFERRALS] REfl Bl DUE:| MTG DATE REV BODY PH NOTICED 1 DATE OF FINAL ACHON:1 4/1 0/ 0.2. CITY COUNCIL: REMARKS~ PZ: BOA: CLOSED:lit/yod BY: I -3--, L ,~ Inct; 1 DRAC: PLAT SUBMITD: j PLAT (BK,PG):~ ADMIN: A-/)967 0 4% NOTICE OF APPROVAL TO: Julie Ann Woods, Community Development Director Joyce Ohlson, Deputy Director FROM: Fred Jarman, Planner, 0 72 RE: Joy Streambank Stabilization Project DATE: April 10, 2002 6149- , 4.V* Joy Streambank Stabilization t i 4. ..r.: ': ../ Project / l r ... I I'll ./ .....el:. 7% |~11160 River drivâ‚¬ r-|1150 River Drivi $ ..1.... Text Road Name Topography 1... ,A/City Line Structures 4 Li~ Water bodies ~ 3,3 Roaring Fork I 1 ,2* ~ parceIs / River ' 1 1 /1 1 W- - E \ 7 1 S 64.._12 2-1 Applicant: William and Sara Joy Project Description: hydrologic forces are eroding the present stream bank along 1150 and Representative: Beach Environmental, LLC 1160 River Drive, shown above. The Applicant is requesting approval to stabilize the bank with Project Location: 1150 River Drive, Aspen an environmentally sensitive design incorporating bio-engineering techniques such Zone District: R-30 (Low-Density Residential) as native plant materials, geotextile mesh, stone- toe protection, and coir logs for a more Recommended Action: Approval with sensitive approach to stabilizing the bank from Conditions further erosion. Staff Comments Due to hydrologic forces that are eroding the present stream bank along 1150 and 1160 River Drive, the applicants, William and Sara JOY, are requesting approval to stabilize the bank with an environmentally sensitive design incorporating bio-engineering techniques such as native plant materials, geotextile mesh, stone-toe protection, and coir logs for a more sensitive approach to stabilizing the bank from furth er erosion. The subject stretch of bank proposed for re-stabilization is approximately 300 feet in length and has been analyzed into five "sites." A brief summary of the sites and proposed actions are listed below: Site 1: The applicants placed an 85-foot long stone wall with a slope of 2:1 along the southeastern portion of the bank several years ago as a "hard fix" to erosion problems. This wall has begun to show signs of undercutting and erosion. The applicants propose to remove the wall and replace with fill, and install vegetative erosion control as specified in the plan. The applicants proposed to add three boulders in the river in this section to divert flow force away from this bank area while providing for fish habitat. Staff strongly disagreed with the boulder additions and requested the applicant remove them from the proposed plan. With this change, Staff finds this to be an appropriate method for stabilization. Site 2: This section is a 35-foot section of steeply eroded bank, which is also failing. The applicants propose to construct a 2:1 slope using vegetative controls. Staff finds this to be an appropriate method for stabilization. Site 3: This section consists of 58 feet of somewhat eroded bank. The remediation proposed for this area is limited to native vegetation planting. Staff finds this to be an appropriate method for stabilization. Site 4: This section consists of 90 linear feet with some boulders placed for limited erosion control. The applicants propose to remove the large boulders and to rebuild the 2:1 slope with native vegetative controls. Staff finds this to be an appropriate method for stabilization. Site 5: This last area consists of a linear stretch of 32 feet, which is currently stabilized with felled logs that are anchored into the slope with ropes to overhanging trees. The applicants proposed to reinforce the felled logs with coir logs (a coir log is a cylindrical structure made of coconut fiber bound together with woven twine to protect slopes from erosion while trapping sediment; they also encourage plant growth within the fiber roll) to reinforce the erosional gaps. Staff finds this to be an appropriate method for stabilization. (Please see tbe detailed written description and site sections provided iÂ·n tbe application tbat outline tbe proposed actions for eacb section.) City of Aspen Parks, Engineering, and Community Development Departments and representative from Beach Environmental, LLC, conducted a site visit on Thursday, May 34, 2001, in order to discuss the proposed project. After discussing the project with Community Development Staff, it is our opinion, that this project can be handled as a Steam Margin "Exemption" which is an administrative action authorized by the Community Development Director pursuant to Section 26.435.040(13) (1) of the Aspen Land Use Code which states: Construction of pedestrian or automobile bridges, public trails, or structures for irrigation, drainage, flood control or water diversion, provided plans and specifications are submitted to tbe City Engineer demonstrating tbat tbe structure is engineered to prevent blockage of drainage cbannels during peak flows and tbe Community Development Director determines tbe proposed structure complies, to tbe extent practical, witb tbe Stream Margin Review Standards. However, given this exemption, the project shall comply, to the extent practical, with the Stream Margin Review Standards including a set of conditions attached with this letter specifically related to this approval. The City of Aspen Parks Department forwarded the following comments regarding this project. Specifically, that 1) a detailed plant list must be submitted prior to the project commencing. The Parks Department shall have final approval for plant species; 2) the applicant should consider mulching the access way into the project area. No trees are permitted to be removed and no excavation should occur within the driplines of the trees; and 3) the City Forester (Stephen) shall be contacted for a site inspection during the project as well as a post project inspection. The Parks Department endorses this project and commends the applicants and project engineer for taking this bio-engineering approach to stabilize the bank, further indicating this is a good project and should be used as a model for future bank stabilization repairs and projects. The City Engineering Department indicated concern as to the potential for down stream scouring or upstream flooding during peak flows as a result of changing the flow dynamics at the Joy property due to this project. Specifically, by altering the way the river flows in direction and capacity, there may be more serious consequences further down stream or upstream as a result. The Engineering Department met with the applicant's representative to determine what impacts might occur and what methods could be used to mitigate them. The Applicant has provided a flood profile analysis to the Engineering department that determined that the placement of 90 cubic yards of material along the stream bank will have an almost imperceptible effect on the river's water surface elevation. This report satisfied all concerns of the Engineering Department. In Summary, the Community Development Department approves this project as a Stream Margin Exemption with the following conditions: Conditions of Approval: 1. That applicant shall ensure the proposed development does not pollute or interfere with the natural changes of the river, stream or other tributary, including erosion and/or sedimentation during construction. 2. The Applicant shall provide written notice to the Colorado Water Conservation Board prior to any alteration or relocation of a watercourse, and a copy of said notice is submitted to the Federal Emergency Management Agency and the Community Development Department. 3. The Applicant shall provide the Community Development Department and Engineering Department with copies of all necessary federal and state permits relating to work within the one-hundred-year floodplain. 4. The Applicant shall provide the Parks Department with an approved detailed plant list prior to the project commencing. 5. The Applicant shall contact the City Forester (Stephen Ellesperman) for a site inspection during the project as well as a post project inspection. 6. The Applicant shall provide a letter from Mike Claffy at the Army Corps of Engineers approving the work to the Engineering Department. Community Development Director Decision The Community Development Director finds the Stream Margin Review Exemption is consistent with the review criteria, and hereby approves the exemption contingent upon com{pliance with the conditions stated herein and required for this approval. i"1rl *4{M 4 341# j * th . 02 Julie Ann Woods, Community Development Director Date *SUPPORTING DECISION DOCUMENTATION REQUIRED AS PART OF THIS DECISION OF APPROVAL CONSISTING OF THE ATTACHMENTS LISTED BELOW MAY BE FOUND IN THE CORRESPONDING LAND USE FILE AT THE CITY HALL. ATTACHMENTS: Exhibit A -- Review Criteria & Staff Findings Exhibit B -- Application Letter Exhibit A 1) It can be demonstrated that any proposed development, which is in the Special Flood Hazard Area, will not increase the base flood elevation on the parcel proposed for development. This shall be demonstrated by an engineering study prepared by a professional engineer registered to practice in the State of Colorado which shows that the base flood elevation will not be raised, including, but not limited to, proposing mitigation techniques on or off-site which compensate for any base flood elevation increase caused by the development; and Staff Finding At the time the proposed project was submitted, the Applicant did not present any information indicating that this propose project will not increase the base flood elevation on the parcel proposed for development. However, Staff included a condition of this approval that required the applicant to submit an engineering study to the Engineering Department that demonstrates that any proposed development which is in the Special Flood Hazard Area will not increase the base flood elevation on the parcel proposed for development. Specifically, this shall be demonstrated by an engineering study prepared by a professional engineer registered to practice in the State of Colorado which shows that the base flood elevation will not be raised, including, but not limited to, proposing mitigation techniques on or off-site which compensate for any base flood elevation increase caused by the development. This report has been completed and submitted to the Engineering Department; it determines that the placement of 90 cubic yards of material along the stream bank will have an almost imperceptible effect on the river's water surface elevation. This report satisfied all concerns of the Engineering and Community development Department. 2) The recommendations of the Aspen Area Community Plan: Parks/Recreation/Open Space/Trails Plan and the Roaring Fork River Greenway Plan are implemented in the proposed plan for development, to the greatest extent practicable. Areas of historic public use or access shall be dedicated via a recorded easement for public use. A fisherman's easement granting public fishing access within the high water boundaries of the river course shall be granted via a recorded "Fisherman's Easement;" and, Staff Finding Staff finds that the proposed bank stabilization project is consistent with the Aspen Area Community Plan: Parks/Recreation/Open Space/Trails Plan to the extent practicable by protecting the stream bank from further erosion so that soil is not continually eroded into the stream and thereby increasing sedimentation of soil particulates or suspended solids as well as altering the water course downstream. This is consistent with Goal E of the AACP regarding protecting and enhancing the natural environment. 3) There is no vegetation removed or damaged or slope grade changes (cut or fill) made outside of a specifically defined building envelope. A building envelope shall be designated by this review and said envelope shall be barricaded prior to issuance of any demolition, excavation or building permits. The barricades shall remain in place until the issuance of Certificates of Occupancy; and Staff Finding Staff referred this application to the City Parks Department who forwarded the following comments regarding this project. Specifically, that 1) a detailed plant list must be submitted prior to the project commencing. The Parks Department shall have final approval for plant species; 2) the applicant should consider mulching the access way into the project area. No trees are permitted to be removed and no excavation should occur within the driplines of the trees; and 3) the City Forester (Stephen) shall be contacted for a site inspection during the project as well as a post project inspection. The Parks Department endorses this project and commends the applicants and project engineer for taking this bio-engineering approach to stabilize the bank, further indicating this is a good project and should be used as a model for future bank stabilization repairs and projects. Further, Staff has included as a condition of approval that the applicant shall ensure the proposed development does not pollute or interfere with the natural changes of the river, stream or other tributary, including erosion and/or sedimentation during construction. 4) The proposed development does not pollute or interfere with the natural changes of the river, stream or other tributary, including erosion and/or sedimentation during construction. Increased on-site drainage shall be accommodated within the parcel to prevent entry into the river or onto its banks. Pools or hot tubs cannot be drained outside of the designated building envelope; and Staff Finding Staff has included as a condition of approval that the applicant shall ensure the proposed development does not pollute or interfere with the natural changes of the river, stream or other tributary, including erosion and/or sedimentation during construction. Further, the Applicant shall contact the City Forester (Stephen) for a site inspection during the project as well as a post project inspection. 5) Written notice is given to the Colorado Water Conservation Board prior to any alteration or relocation of a water course, and a copy of said notice is submitted to the Federal Emergency Management Agency; and Staff Finding As a condition of approval, the Applicant shall be required to provide written notice to the Colorado Water Conservation Board prior to any alteration or relocation of a watercourse, and a copy of said notice is submitted to the Federal Emergency Management Agency and the Community Development Department. However, the Applicant does not intend to alter the course of the river as a result of this project. The focus of the project work will be to reinforce the existing bank through a sensitive bio-engineering approach treatment of the bank restabilization with appropriate materials and plants. Staff met with the Applicant and Engineering Department regarding any further studies for watercourse changes. Ultimately, the Engineering Department required, prior to approval, that the Applicant shall conduct a survey of the cross sectioning of the existing and proposed river channel, using 3 sections and said study shall be stamped by a licensed surveyor in the State of Colorado. Further, the Engineering Department required a letter from a professional engineer registered in the State of Colorado stating that no upstream or downstream degradation will result from the proposed project. Finally, the Engineering Department required that the Applicant provide a letter from Mike Claffy at the Army Corps of Engineers approving the work. 6) A guarantee is provided in the event a water course is altered or relocated, that applies to the developer and his heirs, successors and assigns that ensures that the flood carrying capacity on the parcel is not diminished; and Staff Finding The Applicant contends that the watercourse will not be altered as a result of this project. Please refer to the response provided in the review standard number 6 above. More specifically, the Engineering Department required the Applicant to conduct a HEC-RAS computer model analysis to determine upstream and down stream effects of the project. The analysis indicated that the placement of 90 cubic yards of material along the stream bank "will have an almost imperceptible effect on the river's water surface elevation." In addition, "the placement of this material through this reach of the river will have an inconsequential impact and is likely to be similar to the impact of created by such natural phenomena as waves and floating debris. This report satisfied all concerns of the Engineering Department. 7) Copies are provided of all necessary federal and state permits relating to work within the one-hundred-year floodplain; and Staff Finding The Applicant provided a letter from the Army Corps of Engineers to the property owners (Toy) that indicated that the Corps of Engineers had issued a nationwide general permit number 13 which authorizes Â«tbe discbarge of dredged or fill materials in 'waters of tbe United States for bank stabilization." The Corps of Engineers also determined that this project Â« will not affect threatened or endangered species protected by tbe Endangered Species Act. Your project can be constructed under tbis autbority provided tbe work meets tbe conditions listed on tbe enclosed information sheets." The Applicant has further addressed these conditions in their application. 8) There is no development other than approved native vegetation planting taking place below the top of slope or within fifteen (15) feet of the top of slope or the high waterline, whichever is most restrictive. This is an effort to protect the existing riparian vegetation and bank stability; and Staff Finding This project is a bank stabilization project intended to reinforce the stream bank to assist in flood control and correct any further water diversion as a result of the bank erosion. The project will occur at the water's edge, which is below the top of bank. As such the effort of the project to protect the bank stability. Staff has included a condition of approval requiring that the applicant provide the Parks Department with an approved detailed plant list prior to the project commencing. 9) All development outside the fifteen (15) foot setback from the top of slope does not exceed a height delineated by a line drawn at a forty-five (45) degree angle from ground level at the top of slope. Height shall be measured and determined by the Community Development Director using the definition for height set forth at Section 26.04.100 and method of calculating height set forth at Section 26.575.020 (See Figure "A" below for illustrative purposes); and Staff Finding This standard does not apply as the development takes place on the water's edge. 10) A landscape plan is submitted with all development applications. Such plan shall limit new plantings (including trees, shrubs, flowers, and grasses) outside of the designated building envelope on the river side to native riparian vegetation; and Staff Finding Staff has required the applicant to applicant provide the Parks Department with an approved detailed plant list prior to the project commencing. 11) All exterior lighting is low and downcast with no light(s) directed toward the river or located down the slope and shall be in compliance with section 26.575.150; and Staff Finding -2- April 15, 2002 Staff has brought this to the attention of the Applicant and has included the requirement as a condition of this approval. 12) Site sections drawn by a registered architect, landscape architect, or engineer are submitted showing all existing and proposed site elements, the top of slope, and pertinent elevations above sea level; and Staff Finding The applicant has provided extensive detailed site plans including site sections depicting the areas proposed for stabilization with extensive details regarding the mean water elevations and proposed techniques. Ultimately, the Engineering Department required, prior to approval, that the Applicant shall conduct a survey of the cross sectioning of the existing and proposed river channel, using 3 sections and said study shall be stamped by a licensed surveyor in the State of Colorado. Further, the Engineering Department required a letter from a professional engineer registered in the State of Colorado stating that no upstream or downstream degradation will result from the proposed project. Finally, the owners of the property had the property surveyed by High Country Engineering on September 17, 2001. Cross-sections developed through the survey were used in a HEC-RAS computer model to determine the changes in flood elevation that would result from the proposed stream bank stabilization project. The result of the analysis determined that the placement of 90 cubic yards of material along the stream bank would have an almost imperceptible effect on the river's water surface elevation. This report satisfied all concerns of the Engineering Department. 13) There has been accurate identification of wetlands and riparian zones. Staff Finding The Applicant has indicated in response to the Army Corps of Engineers that the proposed bank stabilization does not impair flow into or out of any wetland area. Joy Stream Bank Stabilization Project Roaring Fork River Report Prepared by: Jorine Lawyer & Tara MeGowan Environmental Scientist & Staff Engineer Beach Environmental, LLC March 8, 2001 772~ ZONE X 0 0% PITKIN COUNTY -9. 0 OF ASPEN 1113-~ ZONE X k- fri 44 + 0 f 7736 11#$& 42 4~21 i i PITKIN COUNTY e UNINCORPORATED AREAS 4 ~ 7739 4 DK 080287 4â‚¬ AIVER-\ ~ 7742 ~ ~~~~~ DRIVE V -4 ZONE AE 1 / MOUNTAIN VIEW DRIVE BLACK 1 7746 IRCH -' 7747 DRIVE ZONE #1ZON E X/j 775 ~Â· 13. 7749 7, , -6 C ; il ' 71 . 2 0 1* M ZONE AE 7759 l '' ZONEX ~ - 16 ZONE-X 49 7 7766 -7 7771 (c (744x 4 7775 I \ ft i 7780 ZONE '1 ZONE X CITY OF ASPEN u * 080143 \' 2* - Int - -- 11:rl - ~4 7798 \ &1 -% 7802 ~ 7806 3 ic. 78,0 5 U G 7814 \\ 7819 r .0.0 H 1 1 1 1%4 - CITY OF ASPEN 4 - 1 -7829 080143 2/ 7833 // li < 7837, 1 WAHot Hlâ€¢O 9 PROPOSED ASH HOLE & EXISTING BOULDER j L $0 t SITE 2: STEEP ERODED SLOPE PROPOSED BOULDERS .-4. ACTION: FILL EROSION, INSTALL / - VEGETATIVE EROSION CONTROL, ~ 7743 PROPOSED STONE TOE PROTECTION AND STONE TOE PROTECTION - 0 0 0 ~~ INSTALLED TO HIGH WATER MARK i: O++ +++\\ 50 \0 * g 8 3 6 8\ ACTION: REMOVE WALL, ~~3 i__ 1 1,11 4 / , *\(P \ SITE 1 STONE WALL ("< tb ir,1 /-4 111== REPLACE W/ FILL, AND INSTALL 25 v. VEGErATIVE EROSION CONTROL -, ~ Ir-w=.77.4.8% 4 "6 TW=7749.14 1: ' BW= 7 142 4 6*=7742.49 Li U] i U. 13- , -Il. e Â¥ 7, 7.21 In K / e 3: ONE DECK - . f, 4 '/ / / 7/ 00 /4 7//9 /7 ... /l. /7, 9-,=742.07 - STZ\E EMBANKMENT 8,5 E 40 EXISTING DWELLING 8 Oi /\11 0 S=7746.)34 ~ 1 1 EXISTING TREE - ~ ~.39=77~/76 ~ ~ f N 1 \ ./.49//240 \ \ /40 BY SMALL BOULDERS L_ 61 i E o: SLOPE SUPPORTED( J / / 40 7%-4 -1 44.9~ ~ ACTION: INSTALL VEGETATIVE 51 4 ///11 8~774123 ~ ~~ EROSION CONTROLS 1 7 5 TE + S.OFNE %64PORTED 1 <*6 ~/ ) co~ = ZU] &=Z 8 ao = 3~ LARGE BOULDERS / ACTON: REMOVE BOULDERS ~ 10 3 11- -y- z 211'Qu- S~-z-4 REPLACE WITH FILL AND 24,90 1/ / / INSTALL VEGETATIVE g EROSION CONTROLS J 4.96 \ y Â¢ly ~ ~ TS67744.82 ~BS=7740.30 \7 SITE 5: SLOPE SUPPORTED BY FELLED LOGS ACTION: INSTALL COIR LOGS ADD BOULDERS TO CONTAIN LOGS logr021.1 NOUVZnl 11 ~~~6~6)=Hd~ *GLâ€¢-926(0 0-n 1 -// 1 , ~1~79IVER DR - /1/ -1- .-- -552: , 1 - %--- Â¥ 1 -3 , ' Wk Ill'14.Â· 05 2â‚¬4/ 1 -- ------ -Â»26-=1129#9- --%21=22=1.../ ./ -9 -/ / /055055>~5 0 1 /0,/54/2-11,Â·C - -$ ------%-.-k--EZEZZÂ» /~d*;5*3~> Â·- I --*45Â«<-21- --- -719*38-5715*I 'xdrat a -.---6 1-,fi,SEESÂ»â‚¬2-~'-~'~$ 2--Â·9~f~58 k\\--->- --/ / - - .0 2 -/ ".0-655Â·40~015.6. .Â»F 2%fEET- .515<1-*5 * ~*~.W~t. . . Â»39\ 1111. -1/lq fl///C Project Objective To stabilize banks that are presently threatened by the erosive forces of the river on the Joy property. The existing rock wall no longer provides adequate protection and is beginning to fail due to undercutting and lack of restraint. The pore spaces between the rocks allow sediment to escape and will eventually lead to additional slumping and failure of the slope. A staff engineer and scientist completed an initial survey in October 2000. Design decisions were made using a variety of stream stabilization techniques emphasizing bioengineering. Bioengineering uses vegetation and organic structural materials to provide stability and control erosion while enhancing habitat and stream aesthetics. The use of "hard" barriers such as rock is held to a practical minimum, with the design purpose being to establish a vigorous, sustainable native or naturalized Elantcommunity as the primary erosion control mechanism. There are a variety of bioengineering methods that can be used in different combinations to fit a diverse set of conditions. Using bioengineering in conjunction with principles of fluvial geomorphology will provide an environmentally sensitive protection design. Project Location William and Sara Joy 1150 River Drive Aspen, Colorado 81611 Roaring Fork River in Pitkin County, Colorado, below the confluence of the Roaring Fork River and Castle Creek in the SW 1/4 of Section 1, Township 10 S, Range 85 W. The drainage area is approximately 228 square miles. See vicinity map for details (Figure 1). Roaring Fork River The United States Geological Survey (USGS) maintains historical data from the Roaring Fork River based on various gauging stations along the River. The closest USGS gauging station to the Joy property is located near the intersection with Cemetery Lane. This station provided data from the years 1913-1918 but was taken out of service. Due to the short time period, the flow velocities may not be accurate due to the influence of decadal climatic regimes and post 1918 upstream diversions. However, it should give a general idea of the rivers behavior. The river --- characteristically has low discharge 9 months out of the year during fall and winter, and higher discharges during a typical snowmelt season, April -July (See Figure 2). Construction for this project is recommended in late fall to maximize the growing season for vegetative species and due to the dormancy requirements for cuttings. Beach Environmental. LLC Joy Stream Bank Stabilization nwaring Fork River Flow Velocl.y 1913-1918 (Fig. 2) 3500 - 1 , 1 1 3000 1 i /11 1 1 3/1\ 2500 - i i / i~ i 2000 1 1 1/ 1\1 1500 1 i . i \1 1 1 1 1 \1 1 1 /1 1 1 1000 1\ 1 1 /1 1 500- 1 3 0 -1 Ij- 1 1 0 -1 - ert i = - Jan Feb Mar April May June Jul Aug Sep Oct Nov Dec Month - Average CFS Role of Vegetation in Slope Stability Vegetation interacts with the bank's materials and creates long-term stabilization through the use of a variety of processes. For streambank restoration, the role of vegetation acts threefold. First, root systems will work to bind soil particles together in the streambank, while the exposed branches and leaves will act to trap sediment in those portions that are exposed to water. Second, vegetation structures wilI increase roughness, slowing down the velocity of water and reducing the stress at the soil/water interface. Lastly, vegetation with non-rigid stems such as willows will bend during high flows and effectively armor the bank. Proposed Techniques After review of the Roaring Fork River system on the Joy property, three major restorative techniques were chosen to stabilize the banks since there are several varying conditions that exist across the site. A brief description of each technique and their respective sites will follow. Boulder Clusters: Strategically placed groups of boulders in the base flow channel will provide cover, create scour holes, or areas of reduced velocity. This method benefits streams that exceed 2 cubic feet per second (CFS). Group placement is most desirable and it is most effective in wide shallow streams with gravel beds. The added erosive forces might cause channel and bank failures, however they will be placed in areas upstream of the erosion site to reduce this possibility. This technique was chosen due to the availability of materials on site. See site plan for details. Beach Environmental. LLC Joy Stream Bank Stabilization Average Maximum velocity Brushlavering with Stone Toe Protection: A ridge of quarried rock or stream cobble placed at the toe of the streambank as an armor to detlect flow from the bank, stabilize the slope and promote sediment deposition. This technique will be used in areas that are below the high water line where vegetation cannot be used. This toe protection will be used in combination with soil bioengineering systems. See Figure 4 for details Joint Plantings/ Live Staking: This technique is useful in areas that are presently riprapped and will provide better aesthetics and drainage of the bank. Live stakes are installed between openings of the rock into the stream bank. Joint planting must be implemented during the dormancy period of chosen plant species, late fall to early spring. See Figure 5 for details. Coir Logs: This technique uses cylindrical structures made of coconut fiber or other fibrous material and bound together with woven twine to protect slopes from erosion while trapping sediment. Coir logs encourage plant growth within the fiber roll. They are flexible for molding to the side of the bank and have an effective life of 6 - 10 years. Subsequent to this time, the trapped sediment and vegetation will provide for a stable channel. They are buoyant and require secure anchoring. See Figure 6 for details. Army Corps of Engineers Permitting To protect the banks along the Joy property, fill material will be needed to stabilize some of the undercut banks, thus subjecting this project to the federal permitting process. The Army Corps of Engineers has the authority to issue permits for discharging dredged and fill material into wetlands under the Clean Water Act using a Section 404 permit. However, due to the lengthy permitting process, a Nationwide Permit may substitute for a Section 404 under certain conditions and limitations set by the Corps. Nationwide permits are designed to expedite processing of projects that, individually and cumulatively, have little or no adverse effect on the environment. This project qualifies for a Nationwide Permit #13 Bank Stabilization. The following are terms and conditions set by the Corps under this permitting process. Under each condition there is a written response verifying that our project falls under these conditions. [leach Environmental. LLC Joy Stream Bank Stabilization Bank stabilization activities necessary for erosion prevention are authorized provided that (Modified from Federal Register Vol. 61, No. 241 December 13, 1996): A. No material is placed in excess ofthe minimum needed for erosion protection; The minimum amount of material will be used to stabilize these banks. See engineering plans for details. B. The bank stabilization activity is less than 500 feet in length; The 300 feet of streambank to be protected through this stabilization project is below the maximum length. c. The activity will not exceed an average of one cubic yard per running foot placed along the bank below the plane of the ordinary high water mark or the high tide line; The material placed below the high water mark will not exceed an average of one cubic yard per running foot. Total fill to be used is approximately 140 cubic yards. d. No material is placed in any special aquatic site, including wetlands; Although riffle and pool complexes are present, material will not be placed in any of these sites, or if necessary, impacted pool and riffle sequences will be replaced on-site. Material will only be placed along the bank where it is eroding. e. No material is of the type or is placed in any location or in any manner so as to impair surface water flow into or out of any wetland area; No impairment of flow into or out of any wetland area is proposed. L No material is placed in a manner that will be eroded by normal or expected high flows (properly anchored trees and treetops may be used in low energy areas) Bioengineering stabilization techniques used in this project site are intended to negate this issue. g. The activity is part of a single and complete project. At the time of survey. only 300 feet of bank were in need of stabilization. Bank stabilization activities in excess of 500 feet in length or greater than an average of one cubic yard per running foot may be authorized if the permittee notifies the district engineer in accordance with the "Notification" general condition and the district engineer determines the -- _- _ activity complies with the other terms and conditions of the nationwide permit and the adverse environmental impacts are minimal both individually and cumulatively. (Sections 10 and 404) Beach Environmental, LLC Joy Streambank Stabilization 5 General Conditions requirements for NWP - (Modified from Federal Register Vol. 65, No. 47 March 9,2000) The following are terms and conditions set by the Corps as "general conditions". Under each condition there is a written response verifying that our project falls under these conditions 1) That the activity may not cause more than a minimal adverse effect on navigation. There are no proposed effects on navigation activities on the Roaring Fork River 2) That the structure offill will be properly maintained The use of vegetation for stabilization should result in a maintenance free fill structure. 3) That appropriate erosion and sittation controls will be used and maintained during construction. Erosion and siltation will be kept to a minimum during stabilization installation. 4) That any activity shall not substantially disrupt the movement of indigenous aquatic species unless the primary purpose of the fill is to impound water. Proposed activities are not anticipated to disrupt the movement of indigenous aquatic species. 5) That heavy equipment must be placed on mats or other measures taken to minimize soil disturbance. This requirement will be adhered to. 6) That the actively complies with regional and case specific conditions. This activity complies with all regional and case specific conditions. 7) That the activity will not occur in a component of the National Wild and Scenic River System, nor in a river officially designated by Congress as a "Study River" for possible inclusion in the system while the river is in an official study status. The Roaring Fork River in Colorado is not part of the National Wild & Scenic River System. 8) That the activity will not impair reserved tribal rights, including, but not limited to, reserved water rights and treaty fishing and hunting rights. This activity will not impair any protected federal reserved rights. Beach Environmental, LLC Joy Streambank Stabilization 6 9) That in certain states and individual state water quality certification must be obtained or waived. The Colorado Department of Water Resources was contacted and there are no requirements for this activity. 10) That an individual state coastal zone management consistency concurrence must be obtained and waived in certain states. Not applicable in Colorado 11) That the activity will not jeopardize a threatened or endangered species as identified linder the Endangered Species Act, or destroy or adversely modify the critical habitat of such species and, ifthe presence or proximity of endangered species is known, non-Federal permittee must notify the Corps and wait for its approval Bill Clark, biologist for the Colorado Division of Wildlife has confirmed that there are no threatened or endangered species in this particular area, and in fact a bioengineering project will enhance wildlife habitat, water quality, and fish habitat. 12) U the activity may adversely affect historic properties which the National Park Services has listed on, or are or may be eligible for listing on, the National Register of Historic Places, that the permittee shall notify the Corps and wait for its approval There are no historic properties on site. 13) Where notification is required, that the permittee has compiled with the specific notification provisions, including a delineation where required. A proposed mitigation plan may also be submitted with the "Pre-Construction Notification" or PCN As proposed, notification for this project is not required. 14) Compliance Certification - The permittee who receives a Nationwide Permit Verification must submit a signed certification regarding the completed work and any required mitigation. N/A. The project will not receive a Nationwide Permit Verification. 15) Use of Multiple Nationwide Permits - The use of more than one NWP for a single and complete project is prohibited. Only NWP 13 will be used for this project. 16) Water Supply Intakes - No activity, including structures and work in navigable waters of the U.S. may occur in the proximity of a public water supply intake except where the activity is for repair of the public water supply intake structures or adjacent bank stabilization. Beach Environmental, LLC Joy Streambank Stabilization 7 The activity will not be in the proximity of a public water supply intake. 17) Shellfish Beds - No activity may occur in areas of concentrated shellfish populations. The activity does not occur in areas where shellfish are present. 18) Suitable Material - Fill materials may not consist of unsuitable material such as trash, debris, car bodies, asphalt, etc.. Materials used for construction must be free from toxic pollutants. All fill will be of suitable material and will be approved by Beach Environmental. 19) Mitigation - The project must be designed and constructed to avoid and minimize adverse effect to waters of the US to the maximum extent practicable. Mitigation will be required when necessary to ensure that the adverse effects to the aquatic environment are minimal. No mitigation is necessary for this project. 20) Spawning Areas - Activities including structures and work in navigable waters of the United States or discharges of dredged or fill material, in spawning areas during spawning seasons must be avoided to the maximum extent practicable. Spawning of the native cutthroat trout and non-native rainbow trout takes place in the Spring. Brook and Brown trout are fall spawners. Stabilization work will be scheduled for late fall, winter, or early summer to avoid spawning season. 21) Management of Water Flows - To the maximum extent practicable, the activity must be designed to maintain preconstruction downstream jlow conditions. Furthermore, the activity must not permanently restrict or impede the passage or normal or high flows. The project will not affect downstream flow conditions or restrict normal or high water flows. 22) Adverse Effects from Impoundments - If the activity, including structures and work in navigable waters of the US or discharge creates an impoundment of water, adverse effects to the aquatic system caused by accelerated passage of water shall be minimized to the maximum extent practicable This project will not cause impoundments of water. 23) Waterfowl Breeding Areas - Activities into breeding areas shall be minimized to the _ maximum practicable extent. This project does not affect waterfowl breeding areas. 24) Removal of temporary fills - Any temporary fills must be removed in their entirety and the affected areas returned to their preexisting elevation. Beach Environmental, LLC Joy Streambank Stabilization 8 ' I. All temporary fills will be removed at the conclusion of this project. 25) Designated Critical Resource Waters - Projects are not authorized in critical resource waters without public approval. The Roaring Fork River is not a critical resource water. 26) Fills within 100-year Floodplains - Above grade fills within the 100 year floodplain are not authorized by NWP 29, 39, 40,42,43, and 44. For NWP 12 and 14, the permittee must notify the District Engineer in accordance with General Condition 13 and document that any permanent above grade fills in waters of the US within the 100 year floodplain comply with FEMA construction requirements. N/A. Application is for a Nationwide Permit #13 Site Plan Details: The entire length of stream bank that requires restoration is approximately 300 feet and is broken up into four different sites (see site plan for details). Each site requires different methods of stabilization. Site 1: Stone Wall The existing stonewall extends for approximately 85 linear feet and is not providing adequate erosion protection to the bank. Small gaps between the stones have allowed water to infiltrate, and remove sediment from behind the stonewall and slumping has commenced. The corrective course of action involves removal of the stonewall and rebuilding the slope (2:1) using vegetative erosion controls. The base of the slope will use stone-toe protection up to the high water mark. Geotextile mesh and burlap will be used underneath the stone-toe protection and to hold the fill of the rebuilt slope while the vegetation takes root. Native vegetation provided by Rocky Mountain Native plants will be used above the high-water line and placed in holes made in the geotextile mesh. Additionally, three boulders are proposed to be placed in the Rearing Fork River for water 00 deflection away from the bank and to create fish habitat downstream. See site plan for details. Erosion control techniques are illustrated in greater detail in figures 3 and 4. Beach Environmental, LLC Joy Streambank Stabilization 9 4. Site 2: Steep Eroded Slope This area extends 35 linear feet and is currently failing. The corrective course of action involves rebuilding the slope (2:1) using vegetative erosion controls. The base of the slope will use stone- toe protection up to the high water mark. Geotextile mesh and burlap will be used underneath the stone-toe protection and to hold the fill of the rebuilt slope while vegetation takes root . Native vegetation provided by Rocky Mountain Native plants will be used above the high-water line and placed in holes made in the geotextile mesh. See site plan for details. Erosion control techniques are illustrated in greater detail in figure 4. Site 3: Slope supported by small boulders This area extends 58 linear feet and has small pockets of erosion. Due to the small amount of erosion in this area, only vegetative erosion controls are needed. The stable slope and presence of some vegetation alleviates the need for geotextile mesh in this area. Native vegetation provided by Rocky Mountain Native plants will be used in places sparse of vegetation. See site plan for details. Erosion control techniques are illustrated in greater detail in figure 5. Site 4: Slope supported by large boulders This area extends 90 linear feet; the current erosion protection is large boulders placed under the bank. The corrective course of action involves removing the large boulders, and rebuilding the slope (2:1) using vegetative controls. The base of the slope will use stone-toe protection up to the high water mark. Geotextile mesh and burlap will be used underneath the stone-toe protection and to hold the fill of the rebuilt slope. Native vegetation provided by Rocky Mountain Native plants will be used above the high-water line and placed in holes made in the geotextile mesh. See site plan for details. Erosion control techniques are illustrated in greater detail in figure 4. Site 5: Slope supported by felled logs This area extends 32 linear feet. Current erosion protection is felled logs that are anchored into Beach Environmental, LLC Joy Streambank Stabilization 10 the slope with ropes. The corrective course of action for this area is to install coir logs beneath the felled logs to fill in erosional gaps. The ropes will be removed and boulders will be used to anchor the existing logs. See site plan for details. Erosion control techniques are illustrated in greater detail in figure 6. Beach Environmental, LLC Joy Streambank Stabilization 11 4 1, , 1 1 *,1 =765-- %70- (39-17/111~\Â« 332 Â¢ 0......0 19 1 1. IN NX \ 't\ *1- C I ,#-~ , I rk ./ 3\' \1.14 ~i i- 4 ' Fi . . -1% 1 -\ZES>\#14â€¢ Â«A- 6 .k- k lef A ' : 4. \ 0 * -1 6 P %* 1. 1 irA . - I./. R. \----,--- 2#M; 12 1 8: NÂ« I .- 4 - .f \9 0 f..~LI-_PEW -N-- 1 / 3-1_j i I I al.-oâ€ž,<\:.1 . \i,#4Â«&497--* . 1 11 ... .N '0.. .... . 1 \~ \1 '.' 1 \\6. ir--LE:P*#,re.F:Bill .j , '' i i \ A k.4 ' t -F f . 1 I r 1 *196 4.--.9~ .r--- sfy . Â»â€¢ 1 1 1 ; . 0 0 314 334 i -1- i 300 . I.- .%\2 -Ltrit 1 E) ....24 i d &[3 tq( t I e e ,Â·. .1~ DURSE ~ 0.~\--51'. e:met r~ ) 4. \ . /.-1 -Â«ff- 9~ Â·f il - .lili . 4 4 . %Â«1/1. . - t. "f . U U h vi</ l - 1, 1 . U / . - 7-'jvsÂ·faw*IlÂ·-Â·11-1:11 I 51 */Ant i â€¢ U // -J M . 11 11. p i ... 7-zz:J -â€¢. 4 Â£\ 11 \\ â€¢1\ 1 f 1/7 4< ~->~ ~~ ~7940:.~-*/9..4. 1.6 4 JOY STREAM BANK 5TABIUZATION PROJECT ., BEACH ENVIRONMENTAL LLC VICINITY MAP 715 WEST MAIN STREET FIGURE I SUITE 304 ASPEN, CO 81611 DATE: SCALE: DRAWN BY: JOB NO.: P.H.(970)925-3475 FAX(970)925-4754 11/6/00 1: 12000 USGS 0269 REVISIONS: -TOP OF BANK BOULDER CLUSTER AREA OF EROSION ~ ~ \ SITE 1 (ROCK WALL) \ \\ 02) A METHOD OF LOCATING BOULDER CLUSTERS Boulder clusters to be located based on ~ Cal field conditions. TOP OF BANK NORMAL F-ROCK SHOULD BE STREAM / 2' DIAMETER v F LEVEL 07 / OR LARGER ~H/GH WATER ~ \\ /Xti../ NOT TO SCALE 291Â»9 (300mm) KEY BOULDER INTO STREAMBED CROSS SECTION JOY 5TREAM BANK *TABILIZATION PROJECT ~~ - SUITE 304 BEACH ENVIRONMENTAL LLC DETAIL OF BOULDER CLUSTERS 715 WEST MAIN STREET FIGURE 3 ASPEN, CO 81611 DATE: SCALE: DRAWN BY: JOB NO.: P.H.(970)925-3475 FAX(970)925-4754 11/6/00 NTS JM 0269 REVISIONS: ~ 1996 JOHN McCUU.AH .t</ X 1/7 9 FRONT OF SLOPE \ x ,, >f< ~ BACK OF 1 \ C %. , TERRACE \/ 4XX: 9\ I . ,<l GEOTEXTILE MESH . I AND BURIAP L ./ X >< 6.14 Y | \ I 1/ r Crisscross branches , 5-8 branches/ft. min. (20/linear meter) . 0 placed at random with ) PLAN VIEW regard to size and age. a 1.00 L 4 4...O 4 0 1 .0 11 GEOTEXTILE MESH , .O AND BURLAP p 3. 4 4. 6 0 I A , ' 4 .O .0 4 4/4 0 0 4 .6 .E1 1 4. .0 -001 1 a . 0 4 0 .. 0 0 .00 MHW .0 .0 / I .0 O - 0 \X 0 MLW .0 0a 7 Oa 0 ' 0 10-20 0 -%-66 4 g .6 4 . .0 Â·--- -1 7 0 .4 . a I ..0 . 0 40. ., 34,\4 0 -O :1_ EL- -.q~Sil '\ /55. I I .13\'Ky - --I.Ii- NOTES: /\44\ 1. Tilt branches down into the slope 10.-20' min. 2. Brushlayering may be constructed with non-compacted or compacted backfill without damage to the brush layer. 3. Branches irrespective of length, should protrude 8-18in. (0.20-0.50 meters) beyond the face of the slope. 4. Holes to be cut in burlap to allow plantings through. JOY 5TREAM BANK 5TABIUZATION PROJECT ,, BEACH ENVIRONMENTAL LLC DETAIL OF BRUSH LAYERING 715 WEST MAIN STREET FIGURE 4 SUITE 304 ASPEN, CO 81611 DATE: SCALE: DRAWN BY: JOB NO.: P.H.(970)925-3475 FAX(970)925-4754 11/6/00 NTS )64 0269 REVISIONS: HÂ¥1-InDOM NHOr 6661 Typical use of willow stakes to anchor willow wattles, straw rolls, bio mats, or turf , . reinforcement mats. * / Â·. 7/fil 1 0 //>16 i i\ / //%88 Typical area staking-1 0 / 1-x-O~Se 1 -3ft. (0.3- lm) apart. 7 /11 /747 #37- - ~-- Cut top of stake square. ~ Typical - drive or plant . willow stakes through 4 2 to 5 buds scars shall openings in riprop or * be above the ground. gabions. 79/ MOW. \9666*6/ l 11 18in. (0.5my\.< .t min. 4, Plant 80% of stake length into the ground.104 .~ ~-- Trim branches close. NOTES: 49~5<1 1. Harvest and plant stakes during the dormant season. 3/4-3in. (20-75mm) diameter. 2. Use healthy, straight and live wood at least 1 year old. 3. Make clean cuts and do not damage stakes or split ends during ~... .- Make angled cut at butt-end. installation, use a pilot bar in firm soils. . . plant butt-end down. 4. Sock cuttings for 24 hours (min.) prior to installation. 5. Tamp the soil around the stake. ~ 2000 JOHN McCULLAH JOY 5TREAM BANK STABIUZATION PROJECT ., BEACH ENVIR0NMENTAL LLC DETAIL OF JOINT FLANTING5 715 WEST MAIN STREET FIGURE 5 SUITE 304 ASPEN, CO 81611 DATE: SCALE: DRAWN BY: JOB NO.: P.H.(970)925-3475 FAX(970)925-4754 11/6/00 NTS IM 0269 REVISIONS: -21-L . . . PLACE COIR ROLLS PARALLEL TO THE STREAMBANK ALONG .#*- A HORIZONTAL CONTOUR ,#- \.AL i I ./ 12" 4, 2/7 .4 / 1 t.'- : :' 4G 1 / d - ..:ilv-'+I::. e- t.. 4 ; 1 1/2" X 1 1/2" k./ 43 (38 X 38 mm) DOUBLE STAKES OPTIONAL 9-V RECOMMENDED t REQUIRED FOR OFFSHORE l- LENGTH OF STAKE INSTALLATION DETERMINED BY THE SUBSTRATE PLACE COIR ROLL SUCH THAT THE ROLL EXTENDS F 2" (50 mm) ABOVE MEAN WATER ELEVATION , \%4 -//13- 1 1 10*1 1 y.: t i~. MEAN WATER r<.lift. ELE144770/Vn 1 - 9?;0 " -Ii----- ----22 \2 /79 71 - ' ' . 4-gAAQ.i Â· /Â·01.i AIL' ..illtÂ·[( 11 /4 64>. i-, 4% i \FA /. 7.-DRIVE STAKE THROUGH NETTING *~ $ - .:X NOT TO SCALE V JOY 5TREAM BANK 5TABIUZATION PROJECT ,, BEACH ENVIR0NMENTAL LLC DETAIL OF COIR LOG5 715 WEST MAIN STREET FIGURE G SUITE 304 ASPEN, CO 81611 DATE: SCALE: DRAWN BY: J08 NO.: P.H.(970)925-3475 FAX(970)925-4754 11/6/00 NTS 061 0269 REVISIONS: ~ 1996 JOHN McCUU-AH PLACE -COR ROLLS PARALLEL TO THE STREAMBANK ALONG ~ 1 A HORIZONTAL. CONTOUR ~ h .r .-U ..-...I-/I..+F~/.19/2..#.' A #717* ./-4-: dll/ 1 t.... ' V : 1 -A-6--A- '.Ir 1 1.-n. L+AN:' 'c---f;, 1- : ' W I A _*/ i -- Â· .-, - 1/ U/111 p.~L/Ati. f- 3</C -//1:ir; ~l- ..cllÂ·ci~1 -X /;~- , {11 I / 1 -:-i- W-- , 2 } ' NL....t - - Â·--Â·,---Â·Â·-----Erp: .1....1 +W r v li i . .1 -<t ~TZ.-clmfu .413:=- ...- 41600mm) Â·~ :: < 65*42--~-1 i E. h -- ~ 1 1/2" X 1 1/2" ./1-0 (38 X 38 mm) DOUBLE STAKES OPTIONAL RECOMMENDED ~ - REQUIRED. FOR OFFSHORE Z- - - LENGn+ OF STAKE iNSTALLATION - DETERMINED EY"THE SUBSTRATE PLACE_Cala ROLL SUCH. THAT. THE. ROLL EkIENDS_ 0----â‚¬3Â· (EfI_rrIrrdrAMEAASIikA-026616*A,NA,nw~ r.. Ar---0 -- '41 r MEAN WATER - -. .<31:7 a .0\ \ :. ELEVATION-- /04,' -_~_. .:f<-540 \ 2" 22:3 31749/~4,jÂ·~~ ..Flx - - , \24,;1 347-DRIVE STAKE THROUGH NETTING 3-Â·~ Â»64Â· 19:.,2.2:542::Â·031 - us \6\Â»1Â·- e -7 /1 \ NOT TO SCALE V JOY STREAM BANK STABIUZATION PROJECT , - DETAIL OF COIR LOGS J BEACH ENVIRONMENTAL -UC 715 WEST MAIN STREET FIGURE G SUITE 304 I SCALE: ASPEN, CO 81611 . DATE: | DRAWN RY: 1 IDe ke. P.H.(970)925=3475 FAX<970)925-4754 - 11/6/to i Nis :* i 1 :281 REVISIONS: - 1 2// 't./ %Â·.Il ,.... I IR 8%4> t... 1 7i -., ' i : VED Beach * ' OCT -5 2001 Resource Management, LLC Nick Adeh City Engineer City of Aspen 130 South Galena St Aspen, CO 81611 Re: Joy Streambank Stabilization Project Aspen, CO Dear Nick: At your request we have undertaken and completed a flood profile analysis of the Roaring Fork River at the William and Sara Joy property near the northwest city limits of Aspen, Colorado. The Roaring Fork River along the Joy property was surveyed by High Country Engineering on September 17, 2001 and cross-sections developed through the survey were used in a HEC-RAS computer model to determine the changes in flood elevation that would result from the proposed streambank stabilization of the left bank of the Roaring Fork River adjacent to the Joy property. To paraphrase the conclusions of this study and report, the proposed placement of 90 cubic yards of material along this bank will have an almost imperceptible effect on the stream's water surface elevation. In fuct, in order to produce a measurable result it was necessary to calculate the surface water elevation change on a ten-year event. It is the engineer's opinion therefore that the results of this study indicate the addition of 90 cubic yards of fill through this reach of the river will have an inconsequential impact and is likely to be similar to the impact created by such natural phenomena as waves and fioating debris. Therefore, we believe that the City of Aspen can now move forward with the issuance of a permit to allow the streambank stabilization project to proceed. Should you have any questions regarding the HEC study please feel free to give me a call. Sincerely, GarFBeactr Principal 715 W. Main w/ attachment Suite 304 Cc: S. Broderick 02691.streambank_stabilization.100201 Aspen, CO 81611 Tel (970) 925-3475 Fax 925-4754 MEMORANDUM To: Fred Jarman, Planner From: Richard Goulding, Project Engineer Date: May 25, 2001 Re: Joy Stream Meeting Attendance : Nick Adeh, Fred Jarman, Gary Beach, Richard Goulding On Thursday, May 24, 2001 Gary Beach met with the City Engineer, Nick Adeh to discuss the requirements for stabilizing the Joy stream bank. The following conditions are to be met to ensure approval from the engineering department: 1) Completion of a survey of the cross sectioning of the existing and proposed river channel, using 3 sections and is to be stamped by a licensed surveyor in the state of Colorado 2) A letter from a professional engineer registered in Colorado stating that no upstream or downstream degradation will result from the proposed development 3) A letter from Mike Claffy at the Army Core of Engineers approving the work loves Eli 1 Beach Resource Management, LLC IMPACT OF STREAMBANK STABILIZATION PROJ ECT ON FLOOD HEIGHT OF ROARING FORK RIVER Property of William and Sara Joy 1150 River Drive Aspen, Colorado SW W T 10 N. R 85 W 28 September 2001 $0"1.44 e rAWALIT:*4, -- lilli. 2 4 /~. Â·303\STER,?6*~RA William W. Hansen Eumb,JUR#*tr- :ZE Registered Professional Engineer 5 -1 tfy WV I Er *f Red Feather Lakes, Colorado .en r '4,14:(QNAL. trit:<557 4'4,~OF COL~,7 BRM 3.01 William W. Hansen, P.E Water Resource Management Consultant 663 Socorro Trail PO Box 227 1//16.//4:8*/f - Red Feather Lakes, Colorado 80545 (970) 881-3500 28 September '01 Mr. Gary L. Beach Beach Resource Management, LLC 715 West Main, Suite 304 Aspen, Colorado 81611 RE: Flood-Profile Analysis Joy Streambank Stabilization Project Your File No. 0269 Dear Gary: This letter and the attachments thereto constitute our report on an investigation of the hydraulic characteristics of the Roaring Fork River where it flows past the Joy property in Aspen, Colorado. The purpose of the investigation is to evaluate the changes in floodwater elevation that would result from a proposed streambank stabilization project on the left bank of the Roaring Fork along the Joy property. PROCEDURES Basic data and procedures were obtained from 1. the Flood Insurance Study (FIS) for Pitkin County, published by the Federal Emergency Management Agency (FEMA) in June, 1987, 2. a field survey conducted by High Country Engineering on 17 September 2001, 3. computer software developed at the Hydrologic Engineering Center (HEC) of the U.S. Army Corps of Engineers for analysis of river hydraulics; the most recent version is entitled HEC-RAS (River Analysis System), Version 3.0 released January 2001, and includes many modifications and improvements to the earlier version (HEC-2), and 4. our own reconnaissance and examination of the site and your files on 10 September 2001. In addition, we have requested the computer printouts of the input and output files of the FIS to see if the data can be incorporated into our investigation. Presumably it is the events of September 11th that have delayed the processing of our order by the FEMA archives in Virginia. - Mr. Cary L. Beach 28 September '01 Page 2 PROJECT LOCATION The study area is approximately one mile northwest of downtown Aspen, as shown on Figure 1. The base map for Figure 1 is the Flood Insurance Rate Map (FIRM) for the City of Aspen, published by FEMA as a companion document to the FIS and bearing the same date of publication. Also shown on Figure 1 are the locations of the cross-sections used in the FIS as well as the cross- sections surveyed by High Country Engineering on September 17th (Sl. 52 & 53). It can easily be observed that the FIS cross-sections at DK and DL would be particularly useful if tying these two studies together were of any importance. SUMMARY OF RESULTS The ten-year flood for the Roaring Fork developed in the FlS was used as a baseline discharge for this analysis. A flowrate of 3700 cubic feet per second is reported as the appropriate value for the Roaring Fork immediately upstream from the confluence with Maroon Creek. When - projected onto the geometric configuration of the river in the study reach the profiles plotted on Figure 2 are obtained. [Nb: on several of the figures and tables the elevation is reported as the truncated value of elevation above Mean Sea Level, i.e., an elevation of 7742.65 may be written as 42.65 for convenience.] The profiles are virtually indistinguishable at the vertical scale of Figure 1, which has been exaggerated as much as possible to maximize the difference. Only on Table 1, the standard output format for HEC-RAS, can any difference be detected. The figures in bold represent the elevation of the water surface during the 10-year event. The italicized figures represent the addition of approximately 90 cubic yards of fill material along the left bank required for the stabilization thereof. The maximum increase that is predicted by this procedure is 0.12 feet at the upstream end of the Joy property. This value is not only negligibly small but may be misleading due to the fact that it constitutes the solution to a highly sophisticated mathematical equation with a small change in the value of only one boundary condition. In reality, the complexities and irregularities of the channel, floodplain and river flow will cause departures from predicted flood stages that will be well in excess of 0.12 feet. Mr. Gary L. Beach 28 September '01 Page 3 SUMMARY OF INPUT DATA The geometrical data used in the HEC-RAS simulation were obtained from the field survey conducted by High Country Engineering on September 17th. The cross-sections are shown in their relative locations on Figure 1 and are plotted on Figure 3. The 90 cubic yards of fill material required for the stabilization of the embankment is assumed to be uniformly distributed throughout the 300-foot length of bank on the Joy property. Therefore. the average reduction in cross-sectional area will be approximately 8 square feet. The rectangles in the diagrams of Figure 4 are scaled to approximately 2 feet wide by 4 feet high, or about 8 square feet. The modified configuration of the stream bank has been drawn so as to increase the bank volume by roughly the same area as that of the rectangle. The bank configurations labeled as "Proposed" on Figure 4 resulted in the profile labeled "Proposed" on Figure 1 and the portion of Table 1 headed "With Proposed Embankment Improvements". CONCLUSIONS The linear approximations to the "before and after" geometry of the left bank result in a predicted increase of 0.12 feet in the 10-year water surface elevation. It is our opinion that this purely mathematical result is inconsequential in comparison to the variations in the water surface that are caused by natural phenomena such as waves and floating debris. I hope that this report provides the information needed by staff of the City of Aspen and of Pitkin County. Please feel free to call if there are any questions or need for further investigation. Sincere!~ you7 111Â©HA u. William W. Hansen, P.E. \X/WH/Ig Attachments (5) - 7729 3 ON E X 1 1 4 44 -\ .L n ZONEX 13 + 4 . Er. 11 0 1 - -h- I LtÂ« 0 ~ 7736 4 1<54/0.-A I I ;. 22. . / iv ni \ Sl 1 / Ab F-1 , ~sh, a 7739 i,11 1 (ID Ki- lk, ...' *' S2 / ' ISO RIVER-, 074 DRIVE \. 1. 641#: < 742 40 ZONE A E * Yjdel - C~-* *6. 1 3Â·17- 2-7746 MOLI :Â·Â·i TAI N VIE.Â·iÂ· DRIVE i BLACK 7747 f \\\.\~ ( BIRCH i t' DRIVE C ZONE X EZONE X ~ .-~1~0775~\ 1-?+ e FLOTTD z *--- --+- - #:~ =4%<c. --\ 7749 411*. 2 I - ---241*â‚¬TLI--2-- 1--gi-1417.- <~3 i.''~~21.42.:i ~ ~0 ~~ 1% \ 0224 / W , I. -di f 1.~4~% /023 i ZONE AE- ,;44.2~, i / 7759 /56:. % ..7769 *. ZONE 0-i . i. ... X LF - ZOAE X 2*A 4 1 . 7 ; 1126~* - Ky :\\ 7766 Â¢ 1 1 6 4 jtÂ¢Â· Â·' 2,~*. I '' .31.i:' . 7771 -1 * 30 2 7775 f 2%*e 7780 \2/ C 11 ZONE. M ZONE AE 1 1 41:~22.4 H ~,< 7784 \9-/ J 1, EN I. 1 1 /3 ,#3 -le 6 1 ~ ROIRAVG FORK RIVER ' i \A 5 - ial 1 1 .... M 'Irn' 1441 -- 1 7794 1 . 11:A: 1, cr r C "Â·7798 '' ZONE X 01 : 1 '2| : 1 \ ~ !mI 01 7802 ~ / 101 1<1 09 7806 1- S III \4 11 7810 5 4 -I Figure 1: LOCATION OF STUDY REACH , -_261-EspIE AND CROSS-SECTIONS 1 26/ir --- ' L J, 1 SCALE: 1 inch = 500 feet , , - (Base map from FEMA Flood Insurance Study ..'- QS r -- completed April 1985, published June 1987) 8 - ...459 2--- 8 27 - 72-Pok... .170-â„¢ U f '/Â· 9/ Geometric Data from 17 Sept'01 Survey by High Country Engineering 48 1----4/ 46 i 1 1 1 1 1 1 44 11] 1*21 151-1 L-J 42 - -Streambed 40 --il-- 10-yr WS, existing - 0 - 10-yr WS, proposed 38 36 335 535 625 300 400 500 600 700 Distance, feet (add 102000 to match 1987 FIS) Figure 2: 10-YEAR FLOOD PROFILES Roaring Fork River at Joy Property (10-year flood discharge = 3700 cfs from FEMA Flood Insurance Study dated June 4, 1987) Elevation, feet (add 7700 to match MSL datum) Table 1: RESULTS OF HEC HYDRAULIC SIMULATION 10-year Flood, Roaring Fork River at Joy Property Run 1: EXISTING CONDITIONS Section River Sta Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chi (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft) Upstream 3 3700 39.18 47.14 47.81 0.004957 6.54 572.28 138.75 0.52 Midpoint 2 3700 38.25 46.26 47.24 0.007147 7.95 465.27 88.57 0.61 Downstream 1 3700 36.45 45.62 42.52 46.28 0.002902 6.65 615.15 101.48 0.43 Run 2: WITH PROPOSED EMBANKMENT IMPROVEMENTS Section River Sta Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chi (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft) Upstream 3 3700 39.18 47.26 47.91 0.004760 6.46 581.27 143.17 0.51 Midpoint 2 3700 38.25 46.33 47.34 0.007467 8.06 459.26 89.15 0.63 Downstream 1 3700 36.45 45.69 42.62 46.35 0.002902 6.65 616.12 101.56 0.43 Figure 3: CROSS-SECTIONS Roaring Fork River at Joy Property Based on field survey of 17 September 2001 by High Country Engineering CROSS-SECTION 1, Upstream Property Line (HEC Sta. 3) 7775 7770 *-4 7765 5 7760 g 7755 ~ 7750 7740 7735 0 50 100 150 200 250 Distance, feet CROSS-SECTION 2, Midpoint of Property (HEC Sta. 2) 7770 7765 ,-4 7760 7755 7750 7745 4 *lt~~*p-*Â·Vi 7740 7735 0 20 40 60 80 100 120 140 160 180 200 Distance, feet CROSS-SECTION 3, Downstream Property Line (HEC Sta. 1) 7770 7765 7760 * C :2 7755 Z 7750 Lu 7745 7740 .\XÂ»-Â»..,04 7735 0 20 40 60 80 100 120 140 160 Distance, feet Elevation Figure 4: APPROXIMATION OF CHANGES TO CONFIGURATION OF CROSS-SECTIONS (Left bank facing downstream) Station 3 (xsec 1) Station 3, Upstream PL (xsec 1) Distance Surveyed Filled 48 C - 46 0 47.99 54.3 46.54 c 44 \12 55.7 46.23 46.23 % 58.4 44.47 45 ; 42 -0- Surveyed 0, 60.8 41.37 43 LU 40 -1- Proposed 65.8 39.68 39.68 38 73.8 39.56 36 0 10 20 30 40 50 60 70 80 Distance, feet Station 2 (xsec 2) Station 2, Intermediate PL (xsec 2) Distance Surveyed Filled 48 46 0 46.48 25.6 46.98 c 44 32.8 45.89 45.89 :2 - Surveyed 35.5 43.57 45 2 42 0, -~ Proposed 36.2 40.44 45 - LU 40 40 39.7 39.7 46.2 38.64 38 57.8 38.8 36 65.8 38.2 0 10 20 30 40 50 60 70 80 Distance, feet Station 1 (xsec 3) Station 1, Downstream PL (xsec 3) Distance Surveyed Filled 48 46 0 43.8 26.3 41.75 41.75 c 44 0 29.4 40.84 41.75 ~ 1 -+-Surveyed 31.1 38.78 40.6 2 42 a, ~ Proposed 35 38.5 38.5 w 40 -, 1 39 38.2 ~_ - 47.3 37.83 38 59.8 37.63 36 0 10 20 30 40 50 60 70 80 Distance, feet joi y(?6#QckÂ«roure <Cp.4 DEPARTMENT OFTHE ARMY U.S. ARMY ENGINEER DISTRICT, SACRAMENTO CORPS OF ENGINEERS 1325 J STREET SACRAMENTO, CALIFORNIA 95814-2922 REPLYTO - ATTENTION OF November 15, 2001 Regulatory Branch (200175496) William and Sara Joy 1150 River Drive Aspen, Colorado 81611 Dear Mr. and Mrs. Joy: We are responding to your request, submitted by Beach Environmental, for a Department of the Army permit to perform streambank stabilization on approximately 300 linear feet of the Roaring Fork River. The project is located just below the confluence of the Roaring Fork River and Castle Creek within the SW 1/4 of Section 1, Township 10 South, Range 85 West, Pitkin County, Colorado. The Chief of Engineers has issued nationwide general permit number 13 which authorizes the discharge of dredged or fill material in waters of the United States for bank stabilization. We have determined that your project will not affect threatened or endangered species protected by the Endangered Species Act. Your project can be constructed under this authority provided the work meets the conditions listed on the enclosed information sheets. You must send a signed letter of certification to the Corps of Engineers within 30 days after completion of the work (see general condition number 14). A copy of the certification statement is included for your use. This verification is valid until February_11,_1001. If you have not completed your project by that time, you should contact the Corps of Engineers to obtain information on any changes which may have occurred to the nationwide permits. You are responsible for remaining informed of such changes and for ensuring that all contract personnel are familiar with the terms and conditions of this permit. ... -2- We have assigned number 200175496 to your project. Please refer to this number in any correspondence with this office. If you have any questions, please contact Mr. Randy Snyder of this office or telephone number (970) 243-1199, extension 12. Sincendly, I -- 1431Â»U- Ke<Jacgbson Chief. tolorado/Gunnison Basin Re#afatory Office 402 Rood Avenue, Room 142 Grand Junction, Colorado 81501-2563 Enclosures Copies Furnished: Mr. Gary Beach, Beach Environmental, LLC, 715 West Main Street, Suite 304, Aspen, Colorado 81611 Pitkin County, 506 East Main Street, Aspen, Colorado 81611 APR-11-2002 07:50 FROM: TO:83-9205439 P.001/012 F, Beach Environmental, LLC LETTER OF TRANSMITTAL TO: Fred Jarman City ofAspen - Comm Dev 130 S. Galena Street Aspen, CO 81611 PA>Q FM: Gary Beach 920- 54 59 RE: Joy Streambank Stabilization DATE: April 11,2002 1905 5 1 +626 /5 7mf INS You yk~ KED.Id Zt |CM 01, 1- Claric Â°p GLO,\S -*Â«2 64Â· 40 441. 5,4- Vetle@7 - -1-61 427--Â·004Â«U #4t Quw w< Â«c- W~ -6 1 4-,1- clA~Ack - w c. 56&6 & 4tu~ 4.4 Wi-lt tra. Ewiv toof Â£_ 61 2- S jaÂ£js 50 4Â°Fc'Ait L 485 will Cuae . Â»7 Please call 925-3475 with any questions about this transmittal. Beach 715 West Main Street Suite 304 Aspen, Colorado 715 W. Alain 970.925.3475 Suite 304 Aspen, CO 81611 lei <970) 925-3475 Fax 925-4754 APR-11-2002 07:50 FROM: TO:83-9205439 P.002/012 To: FILE FM: KKM Date: 2/02 Re: Joy Streambank I spoke with Steve Ellspermann and asked if we needed to secure any tree removing permits, if in case we thought we would have to. He said that so long as the tree is under 6 inches in diameter all we had to do was call him a couple of weeks in advance and have him view the property and mark the tree. As it turns out, I do not think that any trees will need to be removed. 0269_Â»le.doc APR-11-2002 07:50 FROM: Tn::83-9205439 P.003/012 0264 DEPARTMENT OFTHE ARMY 0 .f / li U.S. ARMY ENGINEER DISTRICT, SACRAMENTO CORPS OF ENGINEERS 1325 J STREET SACRAMENTO. CAUFORNIA 95814-2922 ATTENTION OF February 25, 2002 Regulatory Branch (200175496) Mr. William and Sara Joy 1150 River Drive Aspen, Colorado 81611 Dear Mr. and Mrs. Joy: We have extended the construction period under grandfather - --Provis'ions --for expd:ring-nationwide. Department- *11- Ule_Army.. Pe.Kmit number 200175496 to February 11, 2003. All other condition"s Of the permit remain in full force and effect. If you have any questions, please write to Mr. Mark Gilfillan, Colorado/Gunnison Basin Regulatory Office, 402 Rood Avenue, Room 142, or telephone (970> 243-1199, extension 15. Sincerely, Ken Jacobson Chief, Colorado/Gunnison Basin Regulatory Office 402 Rood Avenue, Room 142 Grand Junction, Colorado 81501-2563 Copies Furnished: , /*Mr. Gary Beach, Beach Resource Management, LLC, 715 West Main Slieet-i'--S=-irte--80,4, Asparl, -â€ž.Colo]2*49,81611 Pitkin County, 506 East Main St.reet, AspenT Colora-dE--8'161'r-- --- *.Il.-Ii#. -..Ill/. APR-11-2002 07:50 FROM: TO:83-9205439 P.006/012 INTEROFFICE MEMORANDUM TO: GLB FROM: BT,p SUBJECT: JoÂ¥ FLOODPLAIN REPORT DATE: OCt'OBER 22, 2001 CC: G ary, Nick Adch, Ci4 Engineer, called this afternoon to inform us that the recently submitted report on the Joy Floodplain satisfics all his concerns, According to his direction the next stcp would be to notify the COE of our intention of work. Thc City will then verify compliance when the work has bcen completed. 0269.Adeh floo,!plitin response. 10_22_01.doÂ¢ APR-11-2002 07:50 FROM: TO:83-9205439 P.007/012 - The Aspe~nslitute Aspen Meadows - - -1,4*1â‚¬~*42%%9420742â‚¬42/~*e 2â€¢ PHONS ' -'Â· , Â·FAY -Â· ~ Â·1 66| MFACAAF &8),4- aitaGes ~.TELEPtONED C OAC Â¢.An fÂ»f- 34923 El RETUR*D YOUR CAU - Z ~*,|-~ . ,~2- 02 ,t}Â·,hi/,2, a~ ..C PLEASE- CALL â€¢ Er.,-0 1.-Â·17,M.. tf:17:/93--,L;- i.2.1.ff:,:-ff *12 0 1 44*E#*f-Ya~ 0- *4~84&f**%92#840*26="Lia,~,90:_2--3~6 <ve'.~39?: APR-11-2002 07:51 FROM: TO:83-9205439 P.008/012 L; Â°filtkK< Mit*Ze A 1 oil / 0 4 02.69 Beach . Resource Management. LLC Nick Adeh City Engineer City of Aspen 130 South Galena St ASpen, CO 81611 Re: Joy Streambank Stabilization Project Aspen, CO Dear Nick: At your request we have undertaken and completed a flood profile analysis of the Rom=ing Fork River at the William and Sara Joy property near the northwest city limits of Aspen, Colorado. The Rearing Fork River along the Joy property was surveyed by High Country Engineering on September 17, 2001 and cross-sections developed through the survey were used in a HEC-RAS computer model to determine the changes in flood elevation that would result from the proposed streambank stabilization of the left bank of the Roaring Fork River adjacent to the Joy properly. To paraphrase the conclusions of this study and report, the proposcd placement of 90 cubic yards of material along this bank will have an almost imperceptible effect on the stream's water surface elevation. In fact, in order to produce a measurable result it was necessary to calculate the surface water elevation change on a ten-year event. It is the engineer's opinion therefore that the results of thjs study indicate the addition of 90 cubic yards of fill through this reach of the river will have an inconscquential impact and is likely to be similar to the impact created by such natural phenomena as waves and floating debris. Therefore, we believe that the City of Aspen can now move forward with the issuance of a permit to allow the streambank stabilization project to proceed. Should you have any qucstions regarding the HEC study please feel free to give me a call. Sincerely, Principal /15 W Main w/ artachment Suite 304 Cc: S. Broderick 02691 slreautbank-stabilization. 100201 Aspen Co 81611 Tel (970) (225-3475 Far 975 4754 imi. L- ..il APR-11-2002 07:51 FROM: TO:83-9205439 P. 009/012 0 4 Subject: Date: Mon, 30 Apr 2001 16:02:09 -0600 From: Richard Goulding <richardg@ci.aspen.co.us> To: jorine@beach.resource.com Jorine, Attached is the official response of the Engineering Department in relation to the proposed Bank Stabilization. Sorry about the delay getting this to you today but I wanted to talk to the Army Corps. of Engineers first. r was informed that new regional conditions have recently been put in place for more sensitive rivers such as the Roaring Fork, also they would like to be informed of such proj ects on the Roaring Fork even though it falls within the 500ft limit. If you have further questions please contact me at 970 920 5087 or richardg@ci.aspen.co. US . Richard Goulding Name: Ji,ybankstablisation.doc [3)0Ybankstablisation.do, Type: WINWORD File (application/msword): Encoding: base64 - maq haue new retyonÂ« 1 Conot ,-1-WAS D \A 36.ura-2 , 2. E 2-iuuv , 00 1 8 nit-6.-2 StÂ«arn -46 1, 4.+ 4Â·0 \0<.- n. +Of)1 4 - IM,9 lc, C./lot&!r~M : 4Of =* AA-; S,4â‚¬. Voc Â¢oh/rÂ«_ A,Â·~â‚¬ * lofl 480/015:45 PM APR-11-2002 07:51 FROM: TO:83-9205439 P.010/012 0 0 DRC Joy Slope Stabilization Memo Ref: 1250 Ri verside Drive, Aspen Date: April 30, 2001 The submittal need to include a report by a licensed professional engineer registered in the stale of Colorado with experience in the field of Iiver hydrology/ channel stabilization. The submittal must include the following professional level work: 1) Completion of a survey of the cross sectioning of the existing and proposed river channel 2) Perfunning a HEC- 2 run/ analysis to ensure to ensure no rise or spread of flood tlows beyond floodplain boundaries established by FEMA in the June 1973 Publication. 3) Meet the regional conditions from the Army Coip. of Engineers und inform them of the project if a Nationwide Permit #13 Bank Stabilization is to be used. We are asking for the above so as to avoid any damage to up, down stream or adjacent properties and to safeguard against future related problems. APR-11-2002 07:52 FROM: TO:83-9205439 P. 011 /012 0 0 April 6, 2001 Beach Environmental. LLC Steven Elsperman City Of Aspen 130 S. Galene Aspen, Colorado 81611 Dear Steven Elsperman, JOY STREAMBANK STABILIZATION As you requested, 1 am submitting the site plan and report for the Joy streambank stabilization project We are requesting for an exemption from the stream margin review process. Please review and advise. Fccl free to call with any questions or if additional information is needed. Sincerely, Jorinc 1.awyer Environmental Scientist 7 1 S W. Mdin 5111Â» 304 Aspen, CO 81611 Td (970) 925-3475 Fax 925-4754 APR-11-2002 07:52 FROM: TO:83-9205439 P.012/012 0 0 . Beach Environmental, LLC DATE: 3/26/01 TO: NIC.K [JELACK, COY PTANNER CC; CAKY BEACH, '1'AKA MCCOWA.N FROM: JORINE LAWYER RE: JOY 5IIULAMBANK STABILIZATION I have attached this memo as a supplement to our report to highlighl the Joy Srresinbank Stabilization project on the Roating Fork River. Please view our site plan as a supplement to this memo. The Joy>s presently own two properties adjacent to the Rowing Fork River on 1150 River Drive in thc City of Aspen. Currently the streambank along their propecty is protected by a long rockwall, boulders, and felled trees. This protection has aged, and the hydraulic forces of the river arc croding their property. Beach Environmental was retained by the )oys to consrruct an environmentilly sensitive design that would both stabilize the banks whjle enhancing habitat and stream aesthetics. Our designs incorporate bioengineering, which uses nacive plant materials above the high water line for stabilization, Bclow the high water line, we will be using stone-toe protection. This is similar to what is presently on-site, but we will use a geotextile mesh behind thc stonc to limit erosion of silt and other fine material Coir logs, and boulder clusters are also part of our prolection design. Details of each of these techniques can be found in figures 3-6. This project is small in scale; approximately 300 fect of streambank arc sitcd for stabilization. Wc have already been approved for a Nationwide Permit No. 13 from the Army Corps of Engineers tor thls project and meet all of thrir general arid specific conditions See attached report for details. We are asking the City of Aspen for two things: 1) Approval for the project as is. What is the process and timeframe for approval? What additional information is required? 2) What portions of our proposal need to be removed, if a.ny, if we. would like to expedite tlic process and qualify for an exemption? 0269m.03 1, S * Main Â»ib.Â· .18.1 1 AN'< n. Ll) 8101 i Tel (970) 025Â·3475 r.,x ,72 5 4 P;-1 MEMORANDUM To: Fred Jarman, Planner From: Richard Goulding, Project Engineer Date: May 25,2001 Re: Joy Stream Meeting Attendance : Nick Adeh, Fred Jarman, Gary Beach, Richard Goulding On Thursday, May 24, 2001 Gary Beach met with the City Engineer, Nick Adeh to discuss the requirements for stabilizing the Joy stream bank. The following conditions are to be met to ensure approval from the engineering department: 1) Completion of a survey of the cross sectioning of the existing and proposed river channel, using 3 sections and is to be stamped by a licensed surveyor in the state of Colorado 2) A letter from a professional engineer registered in Colorado stating that no upstream or downstream degradation will result from the proposed development 3) A.letterfrom Ivlike-CtaffraUbe-AmmQ,23 of Engineers approving the work . j 1-t\~nxv ,>v . fl r 11* 1 i>Â·he 1 - 1 Ans- r LE I fi > Vt .1 - 1 0 Beach Environmental, LLC folt[ ./ LI # P .b.f4-.. 1.,1 61 /0 1,9 / - LE /6 Â« C k ne 1 Â¥/1. It- ?14--r i r U a. r j. .i i 1 74 00 -4 Ar 4 JA ..4 0, DATE: 3/26/01 ;-7-- , - TO: NICK LELACK, CITY PLANNER F > CC: GARY BEACI I, TARA MCGOWAN FROM: 1()11!NI< 1.,\Un'IER~ RE: JOY S'1111(,\MBANK STABILIZATION I have attached this memo as a supplement to our report to highlight the joy Streambank Stabilization project on the Roaring Fork River. Please ,view our site plan as a supplement to this memo. C 30: f(yoft (30Â¥ 5 9 -it) for w bile.~ cte i< c {s , The Joy's presently own two properties adjacent to the Roaring Fork River on 1150 River Drive in the City of Aspen. Currently the streambank along their property is protected by a long rockwall, boulders, and felled trees. This protection has aged, and the hydraulic forces of the river are eroding their property. Beach Environmental was retained by the Joys to construct an environmentally sensitive design that would both Mabilize the banks while enhancing habitat and stream aesthetics. Our designs incorporate bioengineering, which uses native plant materials above the high water liny for stabilization. Below the high water line, we will be using stone-toe protection. This is similar to what is presently on-site, but we will use a geotextile mesh behind le stone to -limit erosion of silt and other fine material. Coir logs, and boulder clusters are also part of our protection design. Details of each of these techniques can be found in figures 3-6. This project is small in scale; approximately 329 feet of streambank are sited for stabilization. We have already been approved for a Nationwide Permit No. 13 from the Army Corps of Engineers for this project and meet all of their general and specific conditions. See attached report for details. We are asking the City o f Aspen for two things: 1) Approval for the project as is. What is the process and timeframe for approval? What additional information is required? 2) What portions of our proposal need to be removed, if any, if we would like to expedite the process and qualify for an exemption? 0269m.03 3r L) . 715 W. Main Suite 304 1 A 41 1 ' Aspen. CO 81611 i.u 4 . 9-1 Tel (970) 925-3475 ~,â€žL''Ad y, -k . it f Fax 925-4754 46# A L.~~ ~ W 8e PROPOSED FISH HOLE Z ~- EXISTING BOULDER : PROPOSED BOULDERS SITE 2: STEEP ERODED SLOPE 1 ACTION: FILL EROSION, INSTALL ~ PROPOSED STONE TOE PROTECTION VEGETATIVE EROSION CONTROL, \, 7743- AND STONE TOE PROTECTION - \ 0 -- INSTALLED TO HIGH WATER MARK o 0-\~\ O++ + + +l i k cn k W - 0) 8 D 000 < 0 V . F<-<---0"Lij lili\ SITE 1: STONE WALL 2 g L 1/ r , S < ~ ACTION: REMOVE WALL, 1/ f * 00 0 1 //4 1- -1 Z .-<-9- - veÂ»U.Â«j-Â«t REPLACE W/ FILL, AND INSTALL 61'In -~ ~ VEGETATIVE EROSION CONTROL ~ IV=,,4 .68 4 TW=7749.14 1 / ra / 61>3 BW= 7.42 BW=7742.49 9 I" // 7. 9 3% / 7 / 90 m- , /:. E .~ 11 fl .1 - STONE DECK //// 7 7/Xed . l.. =7742. 7- 1/r ~ 42 7. 9.9 / -Â«C - - EXISTING DWELLING -- 9 2 / /.4 STONE EMBANKMENT- / /Il/ f â€¢Â·f 1 17 4 - .f . ~--f~ 7 04 5=7746.4 1 EXISTING TREE ft p AL BS=774 .76 1 4 - 2 4 + 4 1 1- Â» 11Â·C SITE 3: SLOPE SUPPORTED o A BY SHALL BOOLDERS 3.- g ACTION: INSTALL VEGETATIVE u IiI e 2%5 / ...JU.1 31-7741/73~~ EROSION CONTROLS em ER I/)r-1 7 SITE 4: SLOPE- 40 --4 { - 141 ' f FE~ &=z=E= BY LARGE BOULDERS 4/ / 4 ZR'9 0 L. 1,-~ i r-: :.12 ACTION: REMOVE BOULDERS / 0 ~ 5 h q DWELLING REPLACE WITH FILL AND 2*60 /4 f INSTALL VEGETATIVE -,0 510 F IiI. 1 If 3) EROSION CONTROLS 49~ A 1/ Ar ~,Â·Â·:z~Â¢tip' A I -=i- ey m Â¢f TS&7744.82 ~ BS=7740.30 SITE 3 SLOPE SLIPPERTED BY FILLED LEGS ACTION: INSTALL COIR LOGS ADD BOULDERS TO CONTAIN LOGS 133['Cnlcl NOUVZnlâ‚¬VIG Va,NVaLâ‚¬ REVISIONS: ~LtÂ£-916(0Â£6)'11'd 6 + / 3 k U. 5/ / I.' / - . L /1 1 /+ . ' -/,1 \491 -I 4/ 1 *I .3 I. \ '- X i ~-If~\344129/ -,1/ - , K-/ 1- I --- -- -k' /// - I 1 . -, 1 04/1 / h / // - 1.-7 1 - It: , 1 L *% ./..5.4 ./ j " E : I. .... - --Â·35â‚¬023.-.-7 -, / - /./ t X iff- , >91- .55 1/lk-..ni j :3/ 3.2/3/1 + 02- 044Â« Â£f I &; . lilli /04. . 1 ././*., / 7 .'.di'--- fErELL,09: 0/3/3 -4--# 7 / ~ 1.M/* aÂ»fe./ M*=4 ' -- '1- wri./// ... ,Â«ri , 3' IL Â» 355--*- 1 \ .-. - ..32 #Al.I- /:.72 24, / .. # --2549 1, . , W-,-*--'.---'.----'.--,--,----*g- ..11, , / .4 /1 , I //0 1 , 1 ,/.,3.tfuE*323*0 /Im .-r---'.-"'---+-------.-7----~-,--~--,-----P-'.. / // Â· . ./1/ / 4. .... ---- - - . I .<552/&*-$ ' 4 &*.. -/Â»'.,... - I : fw.4--5-2-- torN-ZOIIÂ«ft' ; I 224Â»-__..~___aci=non .4-9- --------99>:7--L4 /fÂ« 2.-44-_- /7 ... '"' r".I ---rl ~ )...--1 - ---icÂ«32*f--IN- //Â«Â»99Â«10229/4494 tfff/ #~i-9 -\ ---%%.341â‚¬42*r2--1//'' 10/=11 // - /4 35'~4,152+37.~w.5xfiL=**- :\ r # LA#~ z~9190- 'f 'r * 1---intiLIEiL .-I--6-/W -5'. ~4Â« 74-- Â·-ir. L K - * 2%& c/ '.'.--------/4/ \\ 1551<6~E)~%OÂ« - -1.......... Z% <PPY /: -- / 2/ /' / Ii...2404 3--4965 . 6\ \\ Joy Stream Bank Stabilization Project Roaring Fork River Report Prepared by: Jorine Lawyer & Tara McGowan Environmental Scientist & Staff Engineer Beach Environmental, LLC March 8, 2001 Project Objective To stabilize banks that are presently threatened by the erosive forces of the river on the Joy property. The existing rock wall no longer provides adequate protection and is beginning to fail due to undercutting and lack of restraint. The pore spaces between the rocks allow sediment to escape and will eventually lead to additional slumping and failure of the slope. A staff engineer and scientist completed an initial survey in October 2000. Design decisions were made using a variety of stream stabilization techniques emphasizing bioengineering. Bioengineering uses vegetation and organic structural materials to provide stability and control erosion while enhancing habitat and stream aesthetics. The use of "hard" barriers such as rock is held to a practical minimum, with the design purpose being to establish a vigorous, sustainable native oF I - naturalized Mant community as the primary erosion control mechanism. There are a variety of bioengineering methods that can be used in different combinations to fit a diverse set of conditions. Using bioengineering in conjunction with principles of fluvial geomorphology will provide an environmentally sensitive protection design. Project Location William and Sara Joy 1150 River Drive Aspen, Colorado 81611 Roaring Fork River in Pitkin County, Colorado, below the confluence of the Roaring Fork River and Castle Creek in the SW 1/4 of Section 1, Township 10 S, Range 85 W. The drainage area is approximately 228 square miles. See vicinity map for details (Figure 1). Roaring Fork River The United States Geological Survey (USGS) maintains historical data from the Roaring Fork River based on various gauging stations along the River. The closest USGS gauging station to the Joy property is located near the intersection with Cemetery Lane. This station provided data from the years 1913-1918 but was taken out of service. Due to the short time period, the flow velocities may not be accurate due to the influence of decadal climatic regimes and post 1918 upstream diversions. However, it should give a general idea of the rivers behavior. The river characteristically has low discharge 9 months out of the year during fall and winter, and higher discharges during a typical snowmelt season, April -July (See Figure 2). Construction for this project is recommended in late fall to maximize the growing season for vegetative species and due to the dormancy requirements for cuttings. Beach Environmental, LLC Joy Stream Bank Stabilization .goaring Fork River Flow Velocity 1913-1918 (Fig. 2) 3500 - 3000 ; f -* ---â€žI 2500 - / \ \ 2000- i 1500 - â€¢ 1000 - 1 1 500 O 1 11'I Jan Feb Mar April May June Jul Aug Sep Oct Nov Dec Month - Average CFS Role of Vegetation in Slope Stability Vegetation interacts with the bank's materials and creates long-term stabilization through the use of a variety of processes. For streambank restoration, the role of vegetation acts threefold. First, root systems will work to bind soil particles together in the streambank, while the exposed branches and leaves will act to trap sediment in those portions that are exposed to water. Second, vegetation structures will increase roughness, slowing down the velocity of water and reducing the stress at the soil/water interface. Lastly, vegetation with non-rigid stems such as willows will bend during high flows and effectively armor the bank. Proposed Techniques After review of the Roaring Fork River system on the Joy property, three major restorative techniques were chosen to stabilize the banks since there are several varying conditions that exist across the site. A brief description of each technique and their respective sites will follow. Boulder Clusters. Strategically placed groups of boulders in the base flow channel will provide cover, create scour holes, or areas of reduced velocity. This method benefits streams that exceed 2 cubic feet per second (CFS). Group placement is most desirable and it is most effective in wide shallow streams with gravel beds. The added erosive forces might cause channel and bank failures, however they will be placed in areas upstream of the erosion site to reduce this possibility. This technique was chosen due to the availability of materials on site. See site plan for details. Beach Environmental. LLC Joy Stream Bank Stabilization Average Maximum velocity Brushlaverine with Stone Toe Protection: A ridge of quarried rock or stream cobble placed at the toe of the streambank as an armor to deflect flow from the bank, stabilize the slope and promote sediment deposition. This technique will be used in areas that are below the high water line where vegetation cannot be used. This toe protection will be used in combination with soil bioengineering systems. See Figure 4 for details Joint Plantings/ Live Staking: This technique is useful in areas that are presently riprapped and will provide better aesthetics and drainage of the bank. Live stakes are installed between openings of the rock into the stream bank. Joint planting must be implemented during the dormancy period of chosen plant species, late fall to early spring. See Figure 5 for details. Coir Logs: This technique uses cylindrical structures made of coconut fiber or other fibrous material and bound together with woven twine to protect slopes from erosion while trapping sediment. Coir logs encourage plant growth within the fiber roll. They are flexible for molding to the side of the bank and have an effective life of 6 - 10 years. Subsequent to this time, the trapped sediment and vegetation will provide for a stable channel. They are buoyant and require secure anchoring. See Figure 6 for details. Army Corps of Engineers Permitting To protect the banks along the Joy property, fill material will be needed to stabilize some of the undercut banks, thus subjecting this project to the federal permitting process. The Army Corps of Engineers has the authority to issue permits for discharging dredged and fill material into wetlands under the Clean Water Act using a Section 404 permit. However, due to the lengthy permitting process, a Nationwide Permit may substitute for a Section 404 under certain conditions and limitations set by the Corps. Nationwide permits are designed to expedite processing of projects that, individually and cumulatively, have little or no adverse effect on the environment. This project qualifies for a Nationwide Permit #13 Bank Stabilization. The following are terms and conditions set by the Corps under this permitting process. Under each condition there is a written response verifying that our project falls under these conditions. Beach Environmental. LLC Joy Stream Bank Stabilization Bank stabilization activities necessary for erosion prevention are authorized provided that (Modified from Federal Register Vol. 61, No. 241 December 13, 1996): A. No material is placed in excess of the minimum needed for erosion protection; The minimum amount of material will be used to stabilize these banks. See engineering plans for details. B. The bank stabilization activity is less than 500 feet in length; The 300 feet of streambank to be protected through this stabilization project is below the maximum length. c. The activity will not exceed an average of one cubic yard per running foot placed along the bank below the plane of the ordinary high water mark or the high tide line; The material placed below the high water mark will not exceed an average of one cubic yard per running foot. Total fill to be used is approximately 140 cubic yards. d. No material is placed in any special aquatic site, including wetlands; Although riffle and pool complexes are present, material will not be placed in any of these sites, or if necessary, impacted pool and riffle sequences will be replaced on-site. Material will only be placed along the bank where it is eroding. e. No material is of the type or is placed in any location or in any manner so as to impair surface water flow into or out Of any wetland area; No impairment of flow into or out of any wetland area is proposed. f. No material is placed in a manner that will be eroded by normal or expected high flows (properly anchored trees and treetops may be used in low energy areas) Bioengineering stabilization techniques used in this project site are intended to negate this issue. g. The activity is part of a single and complete project. At the time of survey, only 300 feet of bank were in need of stabilization. Bank stabilization activities in excess of 500 feet in length or greater than an average of one cubic yard per running foot may be authorized if the permittee notifies the district engineer in accordance with the "Notification" general condition and the district engineer determines the activity complies with the other terms and conditions of the nationwide permit and the adverse environmental impacts are minimal both individually and cumulatively. (Sections 10 and 404) Beach Environmental, LLC Joy Streambank Stabilization 5 General Conditions requirements for NWP - (Modified from Federal Register Vol. 65, No. 47 March 9,2000) The following are terms and conditions set by the Corps as "general conditions". Under each condition there is a written response verifying that our project falls under these conditions 1) That the activity may not cause more than a minimal adverse effect on navigation. There are no proposed effects on navigation activities on the Roaring Fork River 2) That the structure offill will be properly maintained The use of vegetation for stabilization should result in a maintenance free fill structure. 3) That appropriate erosion and siltation controls will be used and maintained during construction. Erosion and siltation will be kept to a minimum during stabilization installation. 4) That any activity shall not substantially disrupt the movement of indigenous aquatic species unless the primary purpose of the fillis to impound water. Proposed activities are not anticipated to disrupt the movement of indigenous aquatic species. 5) That heavy equipment must be placed on mats or other measures taken to minimize soil disturbance. This requirement will be adhered to. 6) That the actively complies with regional and case specific conditions. This activity complies with all regional and case specific conditions. 7) That the activity will not occur in a component of the National Wild and Scenic River System, nor in a river officially designated by Congress as a "Study River" for possible inclusion in the system while the river is in an official study status. The Roaring Fork River in Colorado is not part of the National Wild & Scenic River System. 8) That the activity will not impair reserved tribal rights, including, but not limited to, reserved water rights and treaty fishing and hunting rights. This activity will not impair any protected federal reserved rights. Beach Environmental, LLC Joy Streambank Stabilization 6 9) That in certain states and individual state water quality certification must be obtained or waived. The Colorado Department of Water Resources was contacted and there are no requirements for this activity. 10) That an individual state coastal zone management consistency concurrence must be obtained and waived in certain states. Not applicable in Colorado 11) That the activity will not jeopardize a threatened or endangered species as identified under the Endangered Species Act, or destroy or adversely modify the critical habitat of such species and, if the presence or proximity of endangered species is known, non-Federal permittee must notify the Corps and wait for its approval. Bill Clark, biologist for the Colorado Division of Wildlife has confirmed that there are no threatened or endangered species in this particular area, and in fact a bioengineering project will enhance wildlife habitat, water quality, and fish habitat. 12) If the activity may adversely affect historic properties which the National Park Services has listed on, or are or may be eligible for listing on, the National Register of Historic Places, that the permittee shall notify the Corps and wait for its approval There are no historic properties on site. 13) Where notification is required, that the permittee has compiled with the specific notification provisions, including a delineation where required. A proposed mitigation plan may also be submitted with the "Pre-Construction Notification" or PCN As proposed, notification for this project is not required. 14) Compliance Certification - The permittee who receives a Nationwide Permit Verification must submit a signed certification regarding the completed work and any required mitigation. N/A. The project will not receive a Nationwide Permit Verification. 15) Use of Multiple Nationwide Permits - The use of more than one NWP for a single and complete project is prohibited. Only NWP 13 will be used for this project. 16) Water Supply Intakes - No activity, including structures and work in navigable waters of the U.S. may occur in the proximity of a public water supply intake except where the activity is for repair of the public water supply intake structures or adjacent bank stabilization. Beach Environmental, LLC Joy Streambank Stabilization 7 The activity will not be in the proximity of a public water supply intake. 17) Shellfish Beds - No activity may occur in areas of concentrated shellfish populations. The activity does not occur in areas where shellfish are present. 18) Suitable Material - Fill materials may not consist of unsuitable material such as trash, debris, car bodies, asphalt, etc.. Materials used for construction must be free from toxic pollutants. All fill will be of suitable material and will be approved by Beach Environmental. 19) Mitigation - The project must be designed and constructed to avoid and minimize adverse effect to waters of the US to the maximum extent practicable. Mitigation will be required when necessary to ensure that the adverse effects to the aquatic environment are minimal. No mitigation is necessary for this project. 20) Spawning Areas - Activities including structures and work in navigable waters of the United States or discharges of dredged or fill material, in spawning areas during spawning seasons must be avoided to the maximum extent practicable. Spawning of the native cutthroat trout and non-native rainbow trout takes place in the Spring. Brook and Brown trout are fall spawners. Stabilization work will be scheduled for late fall, winter, or early summer to avoid spawning season. 21) Management of Water Flows - To the maximum extent practicable, the activity must be designed to maintain preconstruction downstream flow conditions. Furthermore, the activity must not permanently restrict or impede the passage or normal or high flows. The project will not affect downstream flow conditions or restrict normal or high water flows. 22) Adverse Effects from Impoundments - If the activity, including structures and work in navigable waters of the US or discharge creates an impoundment of water, adverse effects to the aquatic system caused by accelerated passage of water shall be minimized to the maximum extent practicable This project will not cause impoundments of water. 23) Waterfowl Breeding Areas - Activities into breeding areas shall be minimized to the maximum practicable extent. This project does not affect waterfowl breeding areas. 24) Removal of temporary fills - Any temporary fills must be removed in their entirety and the affected areas returned to their preexisting elevation. Beach Environmental, 1.1..C Joy Streambank Stabilization 8 All temporary fills will be removed at the conclusion of this project. 25) Designated Critical Resource Waters - Projects are not authorized in critical resource waters without public approval. The Roaring Fork River is not a critical resource water. 26) Fills within 100-year Floodplains - Above grade fills within the 100 yearfloodplain are not authorized by NWP 29, 39, 40, 42, 43, and 44. For NWP 12 and 14, the permittee must notify the District Engineer in accordance with General Condition 13 and document that any permanent above grade fills in waters of the US within the 100 year floodplain comply with FEMA construction requirements. N/A. Application is for a Nationwide Permit #13 Site Plan Details: The entire length of stream bank that requires restoration is approximately 300 feet and is broken up into four different sites (see site plan for details). Each site requires different methods of stabilization. Site 1: Stone Wall The existing stonewall extends for approximately 85 linear feet and is not providing adequate erosion protection to the bank. Small gaps between the stones have allowed water to infiltrate, and remove sediment from behind the stonewall and slumping has commenced. The corrective course of action involves removal of the stonewall and rebuilding the slope (2:1) using vegetative erosion controls. The base of the slope will use stone-toe protection up to the high water mark. Geotextile mesh and burlap will be used underneath the stone-toe protection and to hold the fill of the rebuilt slope while the vegetation takes root. Native vegetation provided by Rocky Mountain Native plants will be used above the high-water line and placed in holes made in the geotextile mesh. Additionally, three boulders are proposed to be placed in the Roaring Fork River for water / M - deflection away from the bank and to create fish habitat downstream. \L>/ See site plan for details. Erosion control techniques are illustrated in greater detail in figures 3 and 4. Beach Environmental, LLC Joy Streambank Stabilization 9 Site 2: Steep Eroded Slope This area extends 35 linear feet and is currently failing. The corrective course of action involves rebuilding the slope (2: 1) using vegetative erosion controls. The base of the slope will use stone- toe protection up to the high water mark. Geotextile mesh and burlap will be used underneath the stone-toe protection and to hold the fill of the rebuilt slope while vegetation takes root . Native vegetation provided by Rocky Mountain Native plants will be used above the high-water line and placed in holes made in the geotextile mesh. See site plan for details. Erosion control techniques are illustrated in greater detail in figure 4. Site 3: Slope supported by small boulders This area extends 58 linear feet and has small pockets of erosion. Due to the small amount of erosion in this area, only vegetative erosion controls are needed. The stable slope and presence of some vegetation alleviates the need for geotextile mesh in this area. Native vegetation provided by Rocky Mountain Native plants will be used in places sparse of vegetation. See site plan for details. Erosion control techniques are illustrated in greater detail in figure 5. Site 4: Slope supported by large boulders This area extends 90 linear feet; the current erosion protection is large boulders placed under the bank. The corrective course of action involves removing the large boulders, and rebuilding the slope (2: 1) using vegetative controls. The base of the slope will use stone-toe protection up to the high water mark. Geotextile mesh and burlap will be used underneath the stone-toe protection and to hold the fill of the rebuilt slope. Native vegetation provided by Rocky Mountain Native plants will be used above the high-water line and placed in holes made in the geotextile mesh. See site plan for details. Erosion control techniques are illustrated in greater detail in figure 4. Site 5: Slope supported by felled logs This area extends 32 linear feet. Current erosion protection is felled logs that are anchored into Beach Environmental, LLC Joy Streambank Stabilization 10 the slope with ropes. The corrective course of action for this area is to install coir logs beneath the felled logs to fill in erosional gaps. The ropes will be removed and boulders will be used to anchor the existing logs. See site plan for details. Erosion control techniques are illustrated in greater detail in figure 6. Beach Environmental. 1.-1...C Joy Streambank Stabilization 11 t> 17Â».2 -51 Â» < ~r--- Fl 8 3 . 0.0 -9 -Â· I x. \12: Â£ % i. n. Al~-- it\~Ni -11 1 \\. . 1 4 2 k .< % ~Nk.22:5% r\~ K.=Z:=fict<fOO~--==e= 142 -7--4 /==10194:95. .Â«. C.\\ 4 1.6\\ 52 . \ .0-,1 94 5 1-- 211 0 .A 0 n . \1 \- . 1 hÂ»-Â»-496 4. \th*7443,<R.774 . %. I , 4 U ' 0 /... ..... 1 . i. . ... Ill 6 fLA I . . 12 10 2 .Â· A - . . 03 , ..4>64~: \ 1 I 1 Xhka . U\\ \ ft - * / . 1/ \\ 1 3. .\J // ; 1 -- -\ / / C .6 02> t Â·Â·a up , of 21. -7=34 -. c L -- DURSE Â· .-Â· i erriet -r'Py-\'~- -- ..1 I .3 L . .j .1 ..t :f . .Â· D I / .1 '\ 1 2 ' e 4 \4 44 "4*rhl D . ..r- -6 â€¢:-Â·nip#i.â€¢.: i=#: C 4 t. 1 46JL7NH I FF 1 . . 5 ~ ~--1--- 1 * =d. ~ ~" 60Â»Â»433% .4 , 4 V... 1 [~144.i::4 6 .... . Â»4 44(/. /Â»--7/12- \4 . ----7-4 j loA 2/ 1.11 .. â€¢ 1 larrk-46.. vi Â·714- 1 JOY STREAM BANK 5TABIUZATION PROJECT BEACH ENVIRONMENTAL LLC VICINITY MAF 715 WEST MAIN STREET FIGURE I SUITE 304 ASPEN, CO 81611 DATE: SCALE: DRAWN BY: JOB NO.: P.H.(970)925-3475 FAX(970)925-4754 11/6/00 1:12000 USGS 0269 REVISIONS; -TOP OF BANK 1 BOULDER CLUSTER \ AREA OF EROSION ~ SITE 1 (ROCK WALL) \ :\\ A METHOD OF LOCATING BOULDER CLUSTERS Boulder clusters to be located based on r- field conditions. TOP OF BANK NORMAL F-ROCK SHOULD BE STREAM 1 2' DIAMETER 1/ F 6 / OR LARGER ~HIGH WATER ~ <f \\ /375: - / r</ 11 STREAMBED ., NOT TO SCALE 12" ~ L /40/111\ (300mm) KEY BOULDER INTO STREAMBED CROSS SECTION JOY STREAM [3ANK STABILIZATION PROJECT ,, BEACH ENVIR0NMENTAL LLC DETAIL OF BOULDER CLUSTERS 715 WEST MAIN STREET FIGURE 3 SUITE 304 ASPEN, CO 81611 DATE: SCALE: DRAWN BY: JOB NO.: P.H.(970)925-3475 FAX(970)925-4754 11/6/00 NTS JM 0269 REVISIONS: ~ 1996 JOHN McCULLAH FRONT OF SLOPE ~ BACK OF TERRACE GEOTEXTILE MESH AND BURLAP XX V Crisscross branches 4 1 5-8 branches/ft. min. (20/linear meter) .0 placed at random with 1 PLAN VIEW 01 9 0 regard to size and age. d .. O ' 4 4 . -0 -4|. 0, 0 1 00 GEOTEX-FILE MESH , .' 0 .0 AND BURLAP 4 06 : d.,o g 9 Â· 3:Â· ~14 4 0 . gO . boo - 43 61' a I 0 4 O .. 0 MHW .0 .0 O 6Â· O 00 4 .-0 0 -0 ./. 4. I . <7 7.6 0, MLW 8 0 <2 400 0 0 10'-20' OIl 4 0 ./ --I 4 . a Â· -O 0 0 - -tit__ a_ 2-494 0 <AW:27/<7- NOTES: /\44\ 1. Tilt branches down into the slope 10.-20' min. 2. Brushlayering may be constructed with non-compocted or compacted backfill without damage to the brush layer. 3. Branches irrespective of length, should protrude 8-18in. (0.20-0.50 meters) beyond the face of the slope. 4. Holes to be cut in burlap to allow plantings through. JOY 5TREAM BANK STABIUZATION PROJECT F, BEACH ENVIRONMENTAL LLC DETAIL OF BRU5M LAYERING 715 WEST MAIN STREET FIGURE 4 SUITE 304 ASPEN, CO 81611 DATE: SCALE: DRAWN BY: JOB NO.: P.H. (970)925-3475 FAX(970)925-4754 11/8/00 NTS JM 0269 REVISIONS: HY11(DOM NHOr 666 L ~ Typical use of willow stakes to anchor willow wattles, /4 straw rolls, bio mats, or turf reinforcement mats. . ...'4? 1 .If â€¢ \ 1-2/ / / % - Iia\4 Typical area staking-1 1 -3ft. 0.3- l m) apart. / L- 773\ /60~ /. / ~--- Cut top of stake square. Typical - drive or plant willow stokes through \< 2 to 5 buds scars shall openings in riprap or be above the ground. gabions. > - 11 4 ' \AT 18in. (0.5%54\.\ 14/ rnin. \\ f Plant 80% of stake length into the ground. &--- Trim branches close. NOTES: 3 /1 4 1. Harvest and plant stakes during the 9) 9 dormant season. /1 2. Use healthy, straight and live wood 34 3/4-Jin. (20-75mm) cliameter. at least l year old. 9/1 3. Make clear} cuts and do not ~~ ~ damage stakes or split ends during , , -*--- Make angled cut at butt-end, installation, use a pilot bar in firm soils. m l. plant butt-end down. 4. Sock cuttings for 24 hours (min.) prior to installation. 5. Tamp the soil around the stake. ~ 2000 JOHN McCULLAH JOY 5TREAM BANK 5TABIUZATION PROJECT ., BEACH ENVIR0NMENTAL LLC DETAIL OF JOINT FLANTING5 715 WEST MAIN STREET FIGURE 5 SUITE 304 ASPEN, CO 81611 DATE: SCALE: DRAWN BY: JOB NO.: P.H.(970)925-3475 FAX(970)925-4754 11/6/00 NTS JM 0269 REVISIONS: PLACE COIR ROLLS PARALLEL TO THE STREAMBANK ALONG ~ A HORIZONTAL CONTOUR /~- in ./. . 0 4 :. /'.4.-2 ': '1 ./ k . , Mf. 1 #f ... ' 1.-4 %111Â¢01 :Jr /Iff d * / r N 3.49 / , I. - i> b , V â‚¬ . -*-- 4 4/7 Â«17/ e A ~ ~~ ~~ I 2 'Y: .U . . I 22 44' # - - , 12" C 16600mrn) -4-0/ f -\ \\ I \\\ . 1 1/2" X 1 1/2" (38 X 38 mm) DOUBLE STAKES OPTIONAL 2 -V RECOMMENDED REQUIRED FOR OFFSHORE l- LENGTH OF STAKE INSTALLATION DETERMINED BY THE SUBSTRATE PLACE COIR ROLL SUCH THAT THE ROLL EXTENDS ~2" (50 mm) ABOVE MEAN WATER ELEVATION 41 -/f t. r M EAN WATER ELEVATION - ' -Â· / -~3. DRIVE STAKE THROUGH NETTING -I.-- -- /. NOT TO SCALE V JOY 5TREAM BANK 5TABILIZATION PROJECT ., BEACH ENVIR0NMENTAL LLC DETAIL OF COIR LOGS 715 WEST MAIN STREET FIGURE G SUITE 304 ASPEN, CO 81611 DATE: SCALE: DRAWN BY: JOB NO.: P.H.(970)925-3475 FAX(970)925-4754 11/6/00 NTS JM 0269 REVISIONS: ~ 1996 JOHN McCULLAH PLACE COR ROLLS PARALLEL TO THE ST: ' 24BANK ALONG ~ A HOR/ZON... CONTOUR /r 1 1 -1 ,I .Â£' -/-~-'Â·* ..\~1{.1. i : ...r 1 Vi j Â£1~ / 0: 2 , . .f , 1 .r- C .4 V 41 I.-tÂ« .5,/De: 90 Â«1 --Â·h_ r~ I. G r - - I .- 'rr . 41 3 ...:U.-j--i..- ' 2- , FT i EL : 6600mn.) Â»774.-14 1 \\' '. U ~7.1 11 0 7 . 4? ~ .6 1' F..i~.Â· . 0~vil i i . 1- / 'bt-- H i Â· 1: i 11 1% 1 t. . 0 ....'-'.Â·.A J ju' An.- ,,~ Wâ‚¬ 1 AlkA f.'t v ,wa- - n I. 6\ i~~alÂ·)4 FOR 1.1)12 F:.S~.4,Â»P //1 i.Â£.4.hÂ·''d TN O 'Â·~ S TART '- V p Â¢ i 5 7Â·Â·in /, Â·Â· 0 1.0-tu..4 1 11-//Â¥ DETERMINED BY IHE SUBSTRATE 6-/-#,4-4 -I - r i i 22(,ek. L:,il.li; C)(,jf..i.- .fHA.? 1,+i '2(N..,1 t"V,â€¢ tr .' - ~ m ' + 1 . :*i,- ..',.. + 6-r~. ..,6..A--ex *tÂ· 5 4,10' j. ...:f tÂ¢/1 43' .12.4 / Af 144 //(.,4/v - 1 7. .:, ..:: ~ r .4 34 Â· 001 ..' '.:\ * 4,142 /&42 7.Â·'i:..~'.,\.7'Sy~ Zf~..1 Â£ ' #7922 Â·: 39..~ 13,-2 : /. 0% KJAKE THROUGH .NETANG - S 1.' : NOT TC SCALE 9 1 ' -'lillil--I=I---....:........ .Â£/W.-./.*./ ... ./ A ~ .JCY STREAM BANK oTAB[ 17*1'109 f'gr.ir' 1 ...41 ctÂ·:ACH ENVIRO:#.6,Il,t' 'le i , frAh. O:, Colie, 1.OGS ~ 0 , ' 1~9 ' MAIN STRFET FIGUFF C Sdi i E 304 45 r J,Zir- - . 7 â‚¬2%77 - - I k â‚¬04 2 : ASPEN, O 016,1 . I 9.AWN 8'' 03; .9 2,929-3475 F A*73)925- Â»4754 ; N .6 1. r-r,â€¢~~~*.,ah i k Â·Â·Â· V.,lot< & ,L. * / * ASPEN / PITKIN COMMUNITY DEVELOPMENT MEMO FROM FRED JARMAN ASPEN CITY PI.AN'XiER PHONE: 970.920.5102 ' 4 3-j Â·AM' - B .1 +I'Â°74Â» 1 0 'c C viJ .* i L.j/â€¢ '14). 1 . I 4 C 14.- 4 3> 6- r. 4 1 -,4 ,- 1,6 2 9 0/ -- â€ž 1 1 130 Souni GAL[NA STREET ASPEN, COLORADO 81611-1975