HomeMy WebLinkAboutFile Documents.1050 Matchless Dr.0113-2020-BRES (20) Racquet Club Condominium
Association Garages
1040 & 1050 MATCHLESS DRIVE
ASPEN (PITKIN COUNTY), COLORADO
DRAINAGE REPORT
Report Date / History:
January 03, 2020 / Initial Permit Review
March 23, 2021 / Permit Resubmittal
Owner: General Contractor:
Racquet Club Condo Association G.F. Woods Construction
c/o: Frias Properties Attn: Greg Woods
730 E. Durant Avenue 430 E. Hyman Avenue
Aspen, Colorado 81611 Aspen, Colorado 81611
Phone: 970-920-2000 Phone: 970-544-1833
Email: Ben@FriasProperties.com Email: Greg@GFWoods.com
Prepared by:
Yarnell Consulting&Civil Design
P.O. Box 3901 229 Midland Avenue
Eagle, Colorado 81631 Basalt, Colorado
Phone: (970) 323-7008
Engineer-of-Record: Justin Yarnell, PE (CO), President
Email: Justin@TheYarnells.com
YARNELL CONSULTING & CIVIL DESIGN
TABLE OF CONTENTS
Table of Contents
Appendices ii
Engineer's Certification 1
1. General Location and Description 2
1.1. Location 2
1.2. Description of Property 2
1.3. Description of Project 2
1.4. Previous Drainage Studies 3
1.5. Adjacent Drainage Issues 3
1.6. Major Drainageway Planning Studies 3
1.7. Site Constraints 3
1.8. Irrigation Facilities 4
1.9. Drainage Easements/Tracts 4
2. Drainage Basins and Sub-Basins 5
2.1. Major Basin Description 5
2.2. Existing Sub-Basin Description 5
2.3. Proposed Sub-Basin Description 5
3. Low Impact Site Design 6
4. Hydrologic Criteria 7
4.1. Storm Recurrence Intervals 7
4.2. Design Rainfall 7
4.3. Runoff Calculation Method 7
4.4. Detention Discharge and Storage Calculation Method 7
4.5. Other Criteria 7
4.6. Sub-Basin Data 8
4.7. Existing (Pre-Redeveloped) Runoff 8
4.8. Proposed (Post-Redeveloped) Runoff 8
4.9. Water Quality Capture Volume and Runoff 8
4.1. Hydrographs 8
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5. Hydraulic Criteria 9
5.1. Design Point for Closed Systems 9
5.2. Flow Capacity of Drainage Facilities 9
5.3. Culvert Design 9
5.4. Storm System Design 9
5.5. Gutter Design 9
5.6. Inlet Design 9
5.7. Open Channel Design 9
5.8. Check/Channel Drop Design 9
5.9. Downstream/ Outfall System Capacity 10
6. Proposed Drainage Facility Design 11
6.1. Water Quality Best Management Practices Design 11
6.2. Detention and Outlet Design 11
6.3. Drainage Easements/Tracts 12
6.4. Off-Site Drainage Facilities 12
6.5. Maintenance 12
7. Conclusions 14
8. References 15
APPENDICES
Maps A
Hydrologic Calculations B
Hydraulic Calculations C
Referenced Documentation D
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ENGINEER'S CERTIFICATION
I hereby affirm that this report and the accompanying plans for the redevelopment of
Racquet Club Condominium Association Garages was prepared by me (or under my direct
supervision) for the owners thereof in accordance with the provisions of the City of Aspen
Urban Runoff Management Plan and approved variances and exceptions listed thereto. I
understand that it is the policy of the City of Aspen that the City of Aspen does not and will
not assume liability for drainage facilities designed by others.
JOHN y `rF1�1
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SIGNATURE: ' ti 47241 i
113 AP/22/2021 j
Justin J.Yarnell ��
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1. GENERAL LOCATION AND DESCRIPTION
1.1. Location
The proposed project is located at 1000 Matchless Drive which is the address of the
common space area tied to residences at 1040 and 1050 Matchless Drive. The area is more
specifically known as Lots 2 and 3, Block 1,Alpine Acres Subdivision, City of Aspen.
1.2. Description of Property
The existing property encompasses a footprint of approximately 31,717 square feet (0.728
acres). It is bounded to the east and south by multi-family residences,west by Matchless
Drive, and north by the Smuggler Racquet Club. Presently, there are two (2) duplex
residences on the property- one (1) on each lot- for a total of four (4) residential units,
with associated asphalt driveway and shared parking area, concrete walks, decks,
landscaping, utilities, and an unnamed creek along the southeast property line. There is a
railroad tie retaining wall along the northeast property line to retain approximately four
(4) feet of the adjacent Smuggler Racquet Club property. Topographically,the site drains
toward the west at moderate slopes of less than approximately five (5) percent except
where landscape berms have been placed. There does not appear to be any storm drainage
infrastructure on or immediately adjacent to the property- not even curb and gutter or a
defined swale along the gravel Matchless Drive.According to Figure 3.1 of the City of Aspen
Urban Runoff Management Plan (URMP),the on-site soils are described as Type C.
1.3. Description of Project
It is proposed to raze the existing asphalt parking area and driveway, retaining wall, and
landscape berm on the subject property. While tree mitigation may occur elsewhere on the
property, the southerly limits of work are constrained to the south edge of the parking
area. No improvements are proposed to the residences, resulting in the extents of
improvements being greater than 1,000 square feet but less than 25% of the entire
property.While numerous large, mature trees are slated to remain, redevelopment of the
area will require the removal and on-site mitigation of several trees which are identified on
the Existing Conditions&Demo Plan sheet C2. In addition to two (2) new garage buildings
totaling four (4) garage units, and refuse / recycling area,the redevelopment will include a
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YARNELL CONSULTING & CIVIL DESIGN
new asphalt driveway, reconstruction of some concrete sidewalks (to connect to the new
driveway), and beamstone curb and retaining walls. Since the work is limited to the
existing asphalt parking area,the ground cover will continue to be primarily impervious -
consisting of asphalt paving and roofs.
There is no curb and gutter or defined swale along Matchless Drive. Furthermore,the road
is still gravel. According to the "Curb & Gutter Locations and Curb &Gutter Deferred Zones"
map in Appendix A of the City of Aspen Engineering Design Standards, this property is not
proposed to be equipped with curb and gutter.
1.4. Previous Drainage Studies
The project site is located within the Smuggler Hunter Basin as defined by Figure 1.2 "City
of Aspen Drainage Basins" within the URMP. In accordance with Section 1.5 of the URMP,
the disturbed area of the project has been designed to provide the water quality capture
volume and detention for the 100-year storm event.
There are no other known previous drainage studies applicable to this project site.
1.5. Adjacent Drainage Issues
There are no known drainage issues adjacent to the subject property.
1.6. Major Drainageway Planning Studies
This project site is not within or immediately adjacent to any major drainageways;
therefore, is not subject to any major drainageway planning studies.
1.7. Site Constraints
The project is constrained by a series of elements. First, the finished floor elevations of the
existing buildings are too low which does not permit optimal positive drainage away from
the buildings. Second, the site includes several large, mature trees that limit the
opportunity for regrading. Finally, there is no storm drainage infrastructure on or
immediately adjacent to the site such that all runoff is conveyed overland.
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When considering all the constraints and the desire to minimize the risk of icing, it
becomes evident that a private, on-site, below-grade storm drainage system is necessary as
part of the project. Combined with the need to keep many of the existing trees on the site,
there is insufficient space on the property to construct a water quality and detention basin
that would conform with the URMP and permit daylighting of the proposed, private storm
system. As such, we have coordinated extensively with the City of Aspen Engineering
Department to permit below-grade chambers to serve both water quality and detention
requirements.
1.8. Irrigation Facilities
There is an unnamed creek that runs along the southeasterly property limit. It is possible
this is utilized for irrigation purposes. The creek is outside the limits of disturbance for the
project; therefore, is not anticipated to impact or be impacted by this project.
1.9. Drainage Easements / Tracts
Based on the Improvement and Topographic Survey for the subject property, prepared by
True North Colorado, there are no existing drainage easements or tracts on the project site.
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2. DRAINAGE BASINS AND SUB-BASINS
2.1. Major Basin Description
The project site is located within the Smuggler Hunter Basin as defined by Figure 1.2 "City
of Aspen Drainage Basins" within the URMP. Based upon a review of aerial
photogrammetry, drainage from the site is conveyed in a southerly direction along
Matchless Drive into Gibson Avenue where it is likely intercepted by curb/gutter and a
public drainage system for ultimate conveyance into the Roaring Fork River. The majority
of this basin appears to consist of single- and multi-family residential development.
2.2. Existing Sub-Basin Description
Based upon site reconnaissance by YCCD, no off-site drainage is tributary to the project
site. First, the height of the retaining wall keeps runoff from the Smuggler Racquet Club
from coming onto the property and instead directs it northwesterly. Second, a landscape
berm to the east contains an unnamed creek outside of the project limits. Finally,the lawn
between the residences and parking lot conveys drainage northwesterly- parallel to the
parking lot.Although a detailed analysis of the existing condition was not deemed
necessary, a cursory review of an aerial photo indicates the sub-basin is approximately
50% impervious. It includes lawn area,trees, roof, and pavement.According to Figure 3.1
of the URMP, the on-site soils are described as Type C.
2.3. Proposed Sub-Basin Description
As defined on Drainage Plan (Proposed) Sheet D1 within the civil engineering drawing set,
the project limits have been studied as a single sub-basin (PR1) for purposes of sizing the
on-site storm drainage system and below-grade stormwater detention system to
accommodate the estimated 100-year volume.Approximately 0.16 acres in area and 91%
impervious, this sub-basin consists of the asphalt driveway and on-grade parking spaces,
garage roofs, concrete walks, and a narrow strip of softscape along the southeasterly limits
of the project. Refer to the Rational Method Drainage Calculations in Appendix B for further
information on the drainage sub-basin.
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3. LOW IMPACT SITE DESIGN
As defined within the URMP, each Major Project is asked to incorporate low impact site
design elements to the maximum extent practical. The limited scope of this project and
numerous site constraints resulted in few opportunities. During initial stages of design, our
team studied the feasibility of green roofs for the new garages. Unfortunately, this was
deemed not financially viable due to the extensive structural and architectural systems that
would be required.
Currently, the parking area is entirely asphalt and sheet-flows northwesterly into
Matchless Drive.As part of this project, the runoff being generated within the limits of
disturbance will be captured by a proposed storm system and routed to a below-grade
stormwater detention system. This will intercept particulates and hydrocarbons which
currently flow freely off the property, while simultaneously recharging the groundwater.
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4. HYDROLOGIC CRITERIA
4.1. Storm Recurrence Intervals
In accordance with the URMP, the 100-year storm event has been studied as the major
storm event. Since all proposed infrastructure is sized to capture, convey, and store runoff
from the major event, it was not deemed necessary to study the 10-year (minor) event.
4.2. Design Rainfall
In accordance with Table 2.3 "Two-Hour Incremental Rainfall Depths for Aspen," the
hydrologic calculations utilize a 100-year, 1-hour precipitation depth of 1.23 inches.
4.3. Runoff Calculation Method
In accordance with Section 3.3 of the URMP, the Rational Method was used to estimate peak
flows from this watershed since the area is less than 90 acres.
4.4. Detention Discharge and Storage Calculation Method
Without a public storm system on or adjacent to the subject parcel, and insufficient
elevation available to daylight a pipe, discharge from the below-grade detention system is
wholly reliant on infiltration. As such, the system is limited to the percolation rate of the
on-site soils which have been estimated by the project's geotechnical engineer to be five (5)
minutes per inch. While we believe it is acceptable to size the below-grade detention
system based upon a release rate that takes into account the lowest percolation rate spread
across the footprint of the system, city engineering staff disagree.As such,we have
substantially over-sized the detention system by assuming a release rate of zero (0). In
accordance with the URMP, the required storage volume was established by multiplying the
impervious area within the limits of work by the 1.23-inch 100-year storm depth for the
city of Aspen. It results in a required 677 cubic feet of storage.
4.5. Other Criteria
There are no other hydrologic calculation methods that have been used within this analysis
that have not been presented in or referenced by the URMP.
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4.6. Sub-Basin Data
Refer to Appendix B for a tabulation of the area, storm frequency, rainfall intensity,time of
concentration, and runoff coefficients for each sub-basin.
4.7. Existing (Pre-Redeveloped) Runoff
Since the release rate from the proposed pond is not governed by or limited to a"pre-
redeveloped" rate but percolation rates of the soil, it was not deemed necessary to evaluate
or calculate the "pre-redeveloped" runoff rate.
4.8. Proposed (Post-Redeveloped) Runoff
Appendix B contains the hydrologic calculations to support the estimated 0.9 CFS of
proposed runoff tributary to the proposed below-grade detention system at Design Point A.
4.9. Water Quality Capture Volume and Runoff
When designing a combined water quality and detention basin,the WQCV is included
within the detention volume. The proposed below-grade detention system has been sized
in the same manner. Therefore, since the detention volume is substantially greater than the
WQCV,the WQCV has been omitted from consideration. For record purposes,the volume is
127 cubic feet and the calculation is included in Appendix C.
4.1. Hydrographs
There are no hydrographs utilized for this project.
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5. HYDRAULIC CRITERIA
5.1. Design Point for Closed Systems
There are no closed systems tied to the city's existing collection system.
5.2. Flow Capacity of Drainage Facilities
Proposed pans, pipes, and inlets have been sized to capture and convey the estimated 100-
year tributary flow rate. Further analysis and discussion are included in the subsequent
sections.
5.3. Culvert Design
No culverts are proposed as part of this project.
5.4. Storm System Design
The proposed, private, on-site storm system has been evaluated utilizing the Storm Sewers
Extension for AutoCAD Civil3D®.Appendix C contains a map of the proposed system and
tabulation of each pipe segment to indicate the system can convey the estimated 100-year
flow rate tributary to it without exceeding 80% of the pipe capacity.
5.5. Gutter Design
The proposed concrete pans and adjacent beamstone curbs on this project have been sized
to convey the estimated 100-year flow rate tributary to them.
5.6. Inlet Design
All the inlets proposed as part of this project have been sized to capture the estimated 100-
year flow rate tributary to them when including a 50% clogging factor.A graph in Appendix
C indicates the capture capacity for each size of inlet.
5.7. Open Channel Design
No open channels are proposed as part of this project.
5.8. Check / Channel Drop Design
There are no check/ channel drops associated with this project.
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5.9. Downstream / Outfall System Capacity
All runoff generated within the limits of the project is tributary to a proposed, on-site,
below-grade detention system beneath the parking area drive aisle. Since the system is
being sized to capture the estimated 100-year flow rate tributary to it and infiltrate the
entirety of the volume, it is anticipated that there will be a reduction in runoff leaving the
site; thereby improving the downstream condition.
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YARNELL CONSULTING & CIVIL DESIGN
6. PROPOSED DRAINAGE FACILITY DESIGN
6.1. Water Quality Best Management Practices Design
The limited scope of this project and numerous site constraints resulted in few
opportunities for on-grade water quality improvements. During initial stages of design, our
team studied the feasibility of green roofs for the new garages. Unfortunately, this was
deemed not financially viable due to the extensive structural and architectural systems that
would be required.
Currently,the parking area is entirely asphalt and sheet-flows northwesterly into
Matchless Drive.As part of this project, the runoff being generated within the limits of
disturbance will be captured by a proposed storm system and routed to a below-grade
stormwater detention system. This will intercept particulates and hydrocarbons which
currently flow freely off the property,while simultaneously recharging the groundwater.
6.2. Detention and Outlet Design
Without a public storm system on or adjacent to the subject parcel, and insufficient
elevation available to daylight a pipe, discharge from the proposed, on-site,below-grade
detention system is proposed to be facilitated entirely by infiltration into the on-site soils.
As such, there is no outlet structure proposed as part of the project.Alternatively, the
release rate is governed by the percolation rate of the on-site soils (estimated by the
project's geotechnical engineer to be five [5] minutes per inch) and the approximately 198-
square foot footprint of the 100-year detention volume. While we believe it is acceptable to
size the below-grade detention system based upon a release rate that takes into account
the lowest percolation rate spread across the footprint of the system, city engineering staff
disagree.As such,we have substantially over-sized the detention system by assuming a
release rate of zero (0). In accordance with the URMP, the required storage volume was
established by multiplying the impervious area within the limits of work by the 1.23-inch
100-year storm depth for the city of Aspen. It results in a required 677 cubic feet of storage.
Calculations for the detention storage volume can be found in Appendix C.
In the event of a storm event which generates runoff greater than the capacity of the
detention system, overflow will occur via Drain Basin B2 since this is the lowest grate of
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YARNELL CONSULTING & CIVIL DESIGN
the proposed, private drainage system. Water will safely backflow up through the grate and
along historic drainage paths in Matchless Drive right-of-way.
6.3. Drainage Easements / Tracts
In accordance with the city's Engineering Standards, a 20-foot easement (approximately
centered on the flowline of the unnamed creek) is proposed to be dedicated by separate
document as part of this project.
6.4. Off-Site Drainage Facilities
All runoff generated on this site is tributary to a proposed, on-site,below-grade detention
system at the low point of the site. Since the system is being sized to capture the estimated
100-year flow rate tributary to it and infiltrate the entirety of the volume, it is anticipated
that there will be a reduction in runoff leaving the site; thereby improving the downstream
condition. There are no off-site drainage facilities anticipated to be negatively impacted by
the proposed redevelopment.
6.5. Maintenance
In general, the drainage design is intended to employ concrete pans and a private storm
drainage system to convey runoff generated within the project limits to a below-grade
detention system beneath the parking lot access aisle. The system shall be constructed on
native, well-draining gravels. Base course shall be placed on the native material to provide
a level surface to receive the StormTech chambers which shall be connected to the
proposed, private storm sewer system. The chambers shall be backfilled with more gravel,
filter fabric on top of this, and soils placed up to proposed finished grade. The base course
shall have a void ratio not less than 0.4 so it, combined with the chambers, can contain the
estimated 100-year detention volume.All discharge from the system shall be accomplished
by infiltration.
Maintenance associated with the storm water infrastructure of the project generally
requires that built-up sediment be removed from the inlets and piping. The below-grade
detention system shall be vacuumed six (6) months after completion of the project, and
annually thereafter. The goal of this process is to remove particulates that have collected
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YARNELL CONSULTING & CIVIL DESIGN
on top of the filter fabric. For more information, refer to the manufacturer's literature
regarding operations and maintenance in Appendix D.
All maintenance shall be done by the Racquet Club Condominium Association, or its
property manager. The contact information for the owner can be found on the cover of this
report.
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7. CONCLUSIONS
In conclusion,the drainage design for the proposed garages and parking lot reconstruction
at 1040 and 1050 Matchless Drive is in full conformance with the City of Aspen URMP.
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8. REFERENCES
• "Flood Insurance Rate Map Number 08097C0358E." Federal Emergency
Management Agency. 15 August 2019.
• Johnson, Richard D. "Geotechnical Engineering Report, Garages, Racquet Club
Condominiums, 1040 & 1050 Matchless Drive,Aspen, Colorado." RJ Engineering&
Consulting. 05 November, 2019.
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APPENDIX A - MAPS
Racquet Club Condominium Association Garages
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YARNELL CONSULTING & CIVIL DESIGN
APPENDIX B - HYDROLOGIC CALCULATIONS
Racquet Club Condominium Association Garages
P.O. Box 3901 YARNELL CONSULTING & 129 Midland Avenue
Eagle,Colorado 81631 Basalt, Colorado 81621
CIVIL DESIGN, LLC
(970) 323-7008 3/22/2021
Project Name: Racquet Club Condominium Association Garages Project No.: 19.010
RATIONAL METHOD DRAINAGE CALCULATIONS
Storm Event: Proposed Jurisdiction: City of Aspen
STORM EVENT: 2 I 5 I 10 I 25 I 100 PERCENT
Soil Type: C RUNOFF COEFF.: C2 Cc Can Cgs C100 IMPERVIOUS
Landscape 0.01 0.05 0.15 0.33 0.49 2.0%
Roof 0.83 0.86 0.87 0.88 0.89 100.0%
w Asphalt 0.83 0.86 0.87 0.88 0.89 100.0%
N Concrete 0.83 0.86 0.87 0.88 0.89 100.0%
Gravel 0.83 0.86 0.87 0.88 0.89 100.0%
SUB- AREA I AREA PER SURFACE CHARACTERISTIC (ac) COMPOSITE
COMPOSITE RUNOFF COEFFICIENTS
BASIN (ac) Landscape Roof Asphalt Concrete Gravel IMPERVIOUS
PR1 0.16 0.01 0.05 0.10 0.77 0.80 0.82 0.84 0.87 93.4%
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
TOTAL 0.16 I 0.01 I 0.05 0.10 0.00 0.00 I 0.77 I 0.80 I 0.82 I 0.84 I 0.87 I 93.4%
P.O. Box 3901 YARNELL CONSULTING & 129 Midland Avenue
Eagle, Colorado 81631 Basalt, Colorado 81621
CIVIL DESIGN, LLC
(970) 323-7008 3/22/2021
Project Name: Racquet Club Condominium Association Garages Project No.: 19.010
RATIONAL METHOD DRAINAGE CALCULATIONS
Storm Event: Proposed STANDARD FORM SF-3 (STORM DRAINAGE SYSTEM DESIGN)
Return Period: 100-YEAR
Rainfall Depth: 1.23
DIRECT RUNOFF TOTAL RUNOFF
BASIN DESIGN AREA RUNOFF tc CxA I Q tc S(CxA) I Q REMARKS
POINT
(AC) COEFF (MIN) (AC) (IN/HR) (CFS) (MIN) (AC) (IN/HR) (CFS)
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13)
PR1 A 0.16 0.87 5.0 0.14 6.33 0.89
r 100-YEAR
*All calculations are per City of Aspen URMP, Chapter 3 3/22/2021 1:11 PM
D:\Dropbox\Project Files\19.010-1040&1050 Matchless Drive,Aspen\Engineering\Drainage\2020.03.23 Permit Resubmittal\Rational Method Calculations
YARNELL CONSULTING & CIVIL DESIGN
APPENDIX C - HYDRAULIC CALCULATIONS
Racquet Club Condominium Association Garages
Hydraflow Storm Sewers Extension for Autodesk® Civil 3D® Plan
Outfall
Outfall
1
2
Project File: Storm Sewer Analysis.stm Number of lines:3 Date: 12/30/2019
Storm Sewers v2020.00
MyReport Page 1
Line Line Line Line Capac Flow Gnd/Rim HGL Gnd/Rim HGL Vel
No. Size Length Slope Full Rate El Dn Dn El Up Up Ave
(in) (ft) (%) (cfs) (cfs) (ft) (ft) (ft) (ft) (ft/s)
1 6 63.000 4.13 1.23 0.40 7953.12 7947.49 7953.46 7950.09 3.00
2 6 47.976 2.50 0.96 0.10 7953.46 7950.09 7954.14 7951.32 2.31
3 6 14.519 2.00 0.86 0.50 7952.95 7947.53 7951.92 7947.82 3.30
Project File: Storm Sewer Analysis.stm Number of lines:3 Date: 12/30/2019
NOTES: **Critical depth
Storm Sewers
Nyloplast Standard Grate Inlet Capacity Chart Basin Outlet Flow Rate
Pipe Size CFS*
This chart is based on equations from the FAAAirport Drainage AC 150/5320- 4" 0.229
5B, 1970,Page 35.Certain assumptions have been made and no two
installations will necessarily perform the same way.Safety factors should 6" 0.662
change with site conditions such that a safety factor 1.25 should be used for an 8" 1.441
inlet in pavement,and a safety factor of2.0 should be used in turf areas. 10" 2.612
12" 4.152
15" 7.126
18" 12.163
24" 25.821
30" 52.173
*Maximum flow capacity before drain basin begins to backfill.
Calculation based on an average pipe slope of 1%.
Nyloplast Standard Grates 8", 10", 12",15",18",24"and 30"
9.00
30"Grate
8.00 .
7.00
6.00 24"Grate This table indicates that the 18-inch grate
5.00 --with just 4 inches of head pressure -- can
4.00 18„ rato capture more than 2 CFS.Assuming 50%
3.00 15"Grate clog factor,the inlet can still capture
2.00 = 12° Se approximately 1 CFS which is more runoff
1.00 : 10"Grate than is generated in the entire sub-basin
0.00 8"Grate
0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 1.10 even though the entire sub-basin is not
tributary to the structure.
Head,Feet
THIS PRINT DISCLOSES SUBJECT MATTER IN WHICH DRAWN BY AWA MATERIAL 3130 VERONAAVE
NYLOPIAST HAS PROPRIETARYRIGHrS.THE RECEIPT (j) BUFORD,GA 30518
OR POSSESSION OF THIS PRINT DOES NOT CONFER, DATE 07MAR00 PI-IN(770)932-2443
TRANSFER,OR LICENSE THE USE OF THE DESIGN OR Nyloplas t FAX(770)932-2490
TECH IICALINFORMATIONSHOWNHEREIN APPDBY CJA PROJECTNO./NANE www.nyloplast-us.com
REPRODUCTION OF THIS PRINT OR ANY INFORMATION .,.,.,.LL
CONTAINED HEREIN,OR MANUFACTURE OF ANY GRATE/COVER
ARTICLE HEREFROM FOR THE DISCLOSURE TO OTHERS DATE 07MAR00 8"-30"STANDARD INLET CAPACITY
IS FORBIDDEN,EXCEPT BY SPECIFIC WRITTEN
PERMISSIONFROMNYT.OPLAST. DWG SIZE A SCALE 1:2 SHEET 1 OF 1 DWG NO. 7001-110-001 REV B
Rectuircd 100-year De-Eer4ior. volume.
-Tc 61 imp oreo, = 2210 + 9320 = CoCo I O S F of roof + pvemerr}
ir. basin PR1
volurne = area.. x ran-611 0l }►,
= 66I0x0.23/14
= 67 S al
j
P.O. Box 3901 YARNELL CONSULTING & 129 Midland Avenue
Eagle, Colorado 81631 Basalt, Colorado 81621
CIVIL DESIGN, LLC
(970) 323-7008 3/22/2021
Project Name: Racquet Club Condominium Association Garages Project No.: 19.010
WATER QUALITY CAPTURE VOLUME CALCULATIONS
TOTAL TREE CANOPY AREA(SF) EFFECTIVE WQCV
TOTAL - — EFFECTIVE
BASIN AREA(AC) IMPERVIOUS CONIFEROUS DECIDUOUS IMPERVIOUS IMPERVIOUSNESS (WATERSHED- REMARKS
AREA(AC) AREA (SF) INCHES) (CF)
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
PR1 0.163 0.152 6610 93.2% 0.230 127
*All calculations are per City of Aspen URMP, Chapter 8
WQCV
3/22/2021 1:09 PM
D:\Dropbox\Project Files\19.010-1040&1050 Matchless Drive,Aspen\Engineering\Drainage\2020.03.23 Permit Resubmittal\Rational Method Calculations
DESIGN
TOOL a.
User Inputs Results
Chamber Model: MC-4500 System Volume and Bed Size
Outlet Control Structure: No
Project Name: RCCA Garages Installed Storage Volume: 769.99 cubic ft.
Engineer: N/A Storage Volume Per Chamber: 106.50 cubic ft.
Project Location: Colorado Number Of Chambers Required: 3
Measurement Type: Imperial Number Of End Caps Required: 2
Required Storage Volume: 655 cubic ft. Chamber Rows: 1
Stone Porosity: 40% Maximum Length: 19.19 ft.
Stone Foundation Depth: 9 in. Maximum Width: 10.33 ft.
Stone Above Chambers: 12 in. Approx. Bed Size Required: 198.31 square ft.
Average Cover Over Chambers: 36 in.
System Components
Design Constraint Dimensions: (15 ft.x 50 ft.)
Amount Of Stone Required: 35.10 cubic yards
Volume Of Excavation(Not Including 49.58 cubic yards
Fill):
EMBEDMENT STONE SHALL BE A CLEAN,CRUSHED AND ANGULAR GRANULAR WELL-GRADED SOIUAGGREGATE MIXTURES,<35%
STONE WITH AN AASHTO M43 DESIGNATION BETWEEN#3 AND#4 FINES,COMPACT IN 12'(300 mm)MAX LIFTS TO 95%PROCTOR
CHAMBERS SHALL MEET ASTM F2418"STANDARD DENSITY.SEE THE TABLE OF ACCEPTABLE FILL MATERIALS.
SPECIFICATION FOR POLYPROPELENE(PP)CORRUGATED CHAMBERS SHALL BE BE DESIGNED IN ACCORDANCE WITH ASTM F2787
WALL STORMWATER COLLECTION CHAMBERS" "STANDARD PRACTICE FOR STRUCTURAL DESIGN OF THERMOPLASTIC
ADS GEOSYTHETICS 6017 NON-WOVEN CORRUGATED WALL STORMWATER COLLECTION CHAMBERS".
GEOTEXTILE ALL AROUND CLEAN,CRUSHED,
ED
ANGULAR EMBEDMENT STONE\ PAVEMENTSI DESIGN ENR GINEER)
`�! BY SITE ENGINEER)
•
\\\,c^ \‘ s',\\\\ \\\ �,\\.\\\\\\\\\\ %.,\ \ \ \\ \\•\\• .
f 2m
PERIMETER STONE 4 ,;':. } ., +' IY' , F.w � (600 mm)MIN" (Zkm)
12•(300 mm)MIN
IXCAVATION WALL ; 4n i� t [ t 41<•c� !�/l)� 1\1 /� r11�` �7•a crPi l�
j ndhi 'ell AIIL
(CAN BE SLOPED I; +,l! 10:72 c ✓CI 1'1 (111 '( \ '��/1111j% �,
OR VERTICAL) :q n�1, !ii �rim. 1111 l•it1011111,
n' '4 ��!II `: fli I lfl k i �� till Y In A\ \\ 7 - (1525 mm)
00
' 9104.17 -ll rikril- Lv �II�J ra J _III_I'I_J� Il JL JP-II Il= *IL*IL= L DEPTH OF STONE TO BE DETERMINED
�JI. iL=1L=Il=ll= -_ �JI.�JL F 11�II�II�J�J�.11�IR�1.=�1P�1. BY SITE DESIGN ENGINEER 9'(230 mm)MIN
12"(300 mm)MIN -
DMC-4500CAP (230 mm)MIN 9'
END C 100'(2540 mm) 12'(300 mm)TYP
SITE DESIGN ENGINEER IS RESPONSIBLE FOR ENSURING
THE REQUIRED BEARING CAPACITY OF SOILS
'MINIMUM COVER TO BOTTOM OF FLEXIBLE PAVEMENT.FOR UNPAVED INSTALLATIONS WHERE RUTTING FROM VEHICLES MAY OCCUR INCREASE COVER TO 30'(750 mm).
'De#errnine, De404iorn sr+err, Drain Time
Volur+r+e..= &95 CF
Sys+ , --ov}P►'ini = 1953 5F
-S c l-incl i ors I✓a4e- = 5 chin/rock
Sys4erK hu)+ : ld) inches
Drain +me. = rock x hei514
5m"nx (a nck
into•
- .300 r is r + 5 hours J
YARNELL CONSULTING & CIVIL DESIGN
APPENDIX D - REFERENCED DOCUMENTATION
Racquet Club Condominium Association Garages
GEOTECHNICAL ENGINEERING REPORT
GARAGES
RACQUET CLUB CONDOMINIUMS
1040 & 1050 MATCHLESS DRIVE
ASPEN, COLORADO
November 5, 2019
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Prepared By: Prepared For:
Engineering Racquet Club Condominium Assoc.
&Consulting,Inc.
268RedGlenwcwd CIiHCSpnnga,hcle CO 81601 1040 & 1050 Matchless Drive
P-(970)230-9208 Aspen, CO 81611
Project No. 19-038G-G1
1040& 1050 Matchless Drive Project No. 19-038G-G1
Aspen,Colorado
TABLE OF CONTENTS
1.0 PROJECT INFORMATION 1
1.1 Purpose and Scope 1
1.2 Proposed Construction 1
1.3 Site Conditions 1
2.0 SITE INVESTIGATION 2
2.1 Subsurface Investigation 2
2.2 Subsurface Conditions 2
2.2.1 Groundwater 3
3.0 SITE GRADING 3
4.0 FOUNDATION RECOMMENDATIONS 4
4.1 Foundations placed on Natural Soils 4
5.0 FOUNDATION AND RETAINING WALLS 5
6.0 FLOOR SLABS 5
7.0 CONCRETE 6
8.0 SURFACE DRAINAGE 6
9.0 LIMITATIONS 6
LIST OF FIGURES
Figure 1 —Approximate Test Hole Locations
Figure 2 —Test Hole Logs and Legend
Summary of Laboratory Test Results
a0
1040& 1050 Matchless Drive Project No. 19-038G-G1
Aspen,Colorado
1.0 PROJECT INFORMATION
1.1 Purpose and Scope
This report presents the results of our geotechnical investigation and recommendations for
design and construction of two garage structures at 1040 & 1050 Matchless Drive in Aspen,
Colorado. The investigation was performed to provide foundation and construction
recommendations for the proposed garages.
The site investigation consisted of geologic reconnaissance and exploratory test hole drilling to
investigate subsurface conditions. Test hole drilling was observed by a representative of RJ
Engineering. Samples obtained during the field exploration were examined by the project
personnel and representative samples were subjected to laboratory testing to determine the
engineering characteristics of materials encountered. This report summarizes our field
investigation, the results of our analyses, and our conclusions and recommendations based on
the proposed construction, site reconnaissance, subsurface investigation, and results of the
laboratory testing.
1.2 Proposed Construction
We anticipate the structures will not have below grade areas and excavation depths will likely be
on the order of 5 feet below grade. Plans indicate the back walls of the structure will act as
retaining walls where an existing timber crib wall is located.
1.3 Site Conditions
The site consists of an asphalt paved parking lot. A timber crib retaining wall is located along
the north side of the parking lot. The timber crib wall is about 4-5 feet in height. The
condominium buildings are located on the south side of the parking lot. Grades are relatively
flat where the garages are planned. The site is landscaped around the parking lot and
condominium buildings.
1 a�
1040& 1050 Matchless Drive Project No. 19-038G-G1
Aspen,Colorado
2.0 SITE INVESTIGATION
2.1 Subsurface Investigation
Two test holes were drilled on October 17, 2019. The test holes were drilled as close to the
center of the proposed structures as possible. We were unable to drill near the center of the
east garage because a vehicle was parked in that area. The approximate test hole locations
are presented on Figure 1.
The test holes were advanced with a Diedrich D90 track mounted rig using 4-inch continuous
flight auger where modified California or a standard split spoon sampler was used to record
blow counts and obtain samples. Test hole logs are presented on Figure 2.
To perform the modified California penetration resistance tests, a 2.0-inch inside diameter
sampler was seated at the bottom of the test hole, then driven up to 12 inches with blows of a
standard hammer weighing 140 pounds and falling a distance of 30 inches utilizing an "auto"
hammer (ASTM D1586). The number of blows (Blow Count) required to drive the sampler 12
inches or a fraction thereof, constitutes the N-value. The N-value, when properly evaluated, is
an index of the consistency or relative density of the material tested. Split spoon samples are
obtained in the same manner, but with a 1.5-inch inside diameter sampler. The test hole logs
and legend are presented on Figure 2.
2.2 Subsurface Conditions
Subsurface conditions encountered in test holes TH-1 and TH-2 consisted of 5 feet of silty sand
fill underlain by natural silty sand and gravel to the maximum explored depths of 12 and 8 feet,
respectively, where practical drill rig refusal was encountered. The fill consisted of a silty sand
with gravel and occasional cobbles and was loose to medium dense. The natural silty sand
contained gravel with abundant cobbles and boulders and was dense to very dense.
Two fill samples had 22 and 29 percent fines (material passing the No. 200 sieve). Atterberg
limit testing indicated the fill was non-liquid and non-plastic. One natural sand sample had 16
percent fines. Atterberg limit testing indicated the natural sand had a liquid limit of 36 and a
plasticity index of 11. The fill samples classified as a silty sand (SM), and the natural sand
sample classified as a silty sand (SM) according to the Unified Soil Classification System
2 ac�
1040& 1050 Matchless Drive Project No. 19-038G-G1
Aspen,Colorado
(USCS). Results of the laboratory testing are summarized in the Summary of Laboratory Test
Results.
2.2.1 Groundwater
Groundwater was not encountered during drilling, and the test holes were backfilled for safety
reasons. We do not anticipate groundwater will be encountered to planned excavation depths.
Variations in groundwater conditions may occur seasonally. The magnitude of the variation will
be largely dependent upon the amount of spring snowmelt, duration and intensity of
precipitation, site grading changes, and the surface and subsurface drainage characteristics of
the surrounding area.
3.0 SITE GRADING
Fills are likely planned at this site to achieve finished grades. Grading plans were not available
at the time of this investigation. Based on drilling and our observations, we believe that material
can be excavated by conventional construction equipment. Large boulders may be
encountered during excavation. The boulders may be of such size that on site splitting may be
required before conventional equipment could remove the material.
We recommend fill slopes be constructed at 2H:1V or flatter. Fill slopes should be protected
from erosion. Surface drainage should be directed around slopes. Surface water ponding
behind or flowing over the face of fill slopes may cause significant erosion and instability.
The on-site soils can be used in site grading fills provided the material is substantially free of
organic material, debris and particles are no larger than 6 inches. Areas to receive fill should be
stripped of vegetation, organic soils and debris. Topsoil is not recommended for fill material.
Imported granular soils should contain less than 30 percent fines (passing No. 200 sieve) and a
maximum particle size of 6 inches. Fill should be placed in thin, loose lifts of 8 inches thick or
less. We recommend fill materials be moisture conditioned to within 2 percent of optimum
moisture content and compacted to at least 95 percent of maximum standard Proctor dry
density (ASTM D 698). Placement and compaction of fill should be observed and tested by a
geotechnical engineer.
3 ��
1040& 1050 Matchless Drive Project No. 19-038G-G1
Aspen,Colorado
4.0 FOUNDATION RECOMMENDATIONS
We believe that the natural sands with gravels, cobbles and boulders encountered at the site
are comparatively favorable for the proposed construction. Existing fill soils are not suitable for
support of foundations. Foundations should be placed on natural sand and gravel soils and not
on existing fill soils. We recommend foundations be placed at least 5 feet below existing grade
or at the natural sand soils, whichever is deeper. As an alternative, existing fill soils could be
removed and replaced with properly placed fill in accordance with section 3.0 of this report.
Foundation recommendations for structures supported by the natural soils are presented below.
4.1 Foundations placed on Natural Soils
Foundations should be constructed on undisturbed natural soils at a depth of at least 5 feet
below existing grade. Existing fill or loose, disturbed soils encountered at foundation level
should be removed and the foundation should be extended to natural soils and/or replaced with
properly compacted fill. We recommend fill be placed in accordance with the specifications
presented in section 3.0.
1. Footings should be placed on undisturbed natural sand and gravel soils or properly
placed fill. Foundations can be designed for a maximum allowable soil pressure of
3,000 psf. Based on experience, we anticipate settlement of footings designed and
constructed as recommended will be about 1-inch or less.
2. Continuous footings should have a minimum width of 16 inches and isolated pads
should have a minimum dimension of 2 feet.
3. The soils below foundations should be protected from freezing. We recommend the
bottom of foundations be constructed at least 3.5 feet below finished exterior grade or as
required by local municipal code.
4. Continuous foundation walls shall be reinforced to span anomalies by assuming an
unsupported distance of 10 feet. Foundation walls acting as retaining structures should
be designed to resist lateral earth pressures as discussed in section 5.0 below.
5. All foundation excavations should be observed by a representative of a geotechnical
engineer prior to placement of concrete.
4 ac�
1040& 1050 Matchless Drive Project No. 19-038G-G1
Aspen,Colorado
5.0 FOUNDATION AND RETAINING WALLS
Retaining and below grade walls should be designed to resist lateral earth pressure. Cast-in-
place foundation and retaining walls can be backfilled with on-site granular soils meeting
recommendations in section 3.0. For a horizontal backslope with properly placed and
compacted fill, the unfactored earth pressure can be estimated using an equivalent fluid
pressure of 45 pcf for the active condition and 60 pcf for an at-rest condition. Site retaining
walls which are separate from the structure and can be expected to deflect to mobilize the full
active earth pressure condition could be designed using an equivalent fluid pressure of 45 pcf.
These values assume that the backfill materials are not saturated. Wall designs should
consider the influence of surcharge loading such as traffic, construction equipment and/or
sloping backfill.
The lateral resistance of foundations for retaining walls are a combination of sliding resistance
of the footing on foundation materials and passive earth pressure at the toe of the wall. Sliding
resistance could be calculated based on a coefficient of friction of 0.45. Passive pressure for
natural soils or compacted fill can be determined using an equivalent fluid pressure of 400 pcf.
Retaining walls and structures should be constructed with a drainage system to drain away any
excess water immediately behind the wall. The drainage system may consist of free-draining
gravel, pipes, drain board and/or weep holes are commonly used for wall drainage.
6.0 FLOOR SLABS
The existing fill and natural on-site soils are suitable to support lightly loaded slab-on-grade
construction. To reduce distress associated with minor differential movement, floor slabs should
be separated from all bearing walls and columns with expansion joints which provide
unrestricted vertical movement. A minimum 4-inch layer of free draining gravel should be
placed beneath lower level slabs. The free draining gravel should have less than 2 percent
passing the No. 200 sieve, less than 50 percent passing the No. 4 sieve and have a maximum
size of 2 inches. All fill placed below floor slabs should be moisture conditioned and compacted
in accordance with the recommendations in section 3.0.
5 a�
1040& 1050 Matchless Drive Project No. 19-038G-G1
Aspen,Colorado
7.0 CONCRETE
Typically, for materials encountered at this site, the concentration of water-soluble sulfate is
negligible/low (Class 0 exposure) degree of sulfate attack for concrete exposed to these
materials. The degree of attack is based on a range of 0.00 to less than 0.10 percent water-
soluble sulfates as presented in the American Concrete Institute Guide to Durable Concrete.
Due to the negligible/low degree, no special requirements for concrete are necessary for this
site.
8.0 SURFACE DRAINAGE
Surface drainage is crucial to the performance of foundations and flatwork. We recommend the
ground surface surrounding the building be sloped to drain away from the structure. We
recommend a slope of at least 6 inches in the first 10 feet for landscape and unpaved areas and
a minimum slope of 2 percent for paved areas. Irrigation should not be discharged within 5 feet
of foundation walls. Backfill around foundations should be moisture conditioned and compacted
as recommended in the section 3.0. Roof downspouts and drains should discharge beyond the
wall backfill area.
9.0 LIMITATIONS
This study was conducted in accordance with generally accepted geotechnical engineering
practices in this area for use by the client for design purposes. The conclusions and
recommendations submitted in this report are based upon the data obtained from exploratory
test holes, field reconnaissance and anticipated construction. The nature and extent of
subsurface variations across the site may not become evident until excavation is performed. If
during construction, conditions appear to be different from those described herein; this office
should be advised at once so reevaluation of the recommendations may be made. We
recommend on-site observation of excavations by a representative of the geotechnical
engineer.
The scope of services for this project did not include, specifically or by implication, any
environmental or biological (e.g., mold, fungi, and bacteria) assessment of the site or
identification or prevention of pollutants, hazardous materials or conditions or biological
6 ac�
1040& 1050 Matchless Drive Project No. 19-038G-G1
Aspen,Colorado
conditions. If the owner is concerned about the potential for such contamination, conditions or
pollution, other studies should be undertaken.
The report was prepared in substantial accordance with the generally accepted standards of
practice for geotechnical engineering as exist in the site area at the time of our investigation.
No warranties, express or implied, are intended or made.
Respectfully Submitted,
RJ Engineering & Consulting, Inc.
Richard D. Johnson, P.E.
Principal
7 �c�
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LEGEND: PROJECT NO: PROJECT
19-038G-G1 1040& 1050 Matchless Drive,Aspen
TH-1 Indicates approximate test hole location o 1o. 20'
® NJ� Approximate Figure
NOTES: ,r SCALE: 1" =20'
Test Hole Locations 1
1. Base plan by Bryan May Architecture.
TH-1 TH-2
0 �1 0
— � — Sample Types
• Modified California Sampler. The symbol 7/12 indicates that 7
— 07/12 blows from a 140 pound hammer falling 30 inches was used to
_ _ _ drive a 2-inch I.D.sampler 12 inches.
.117/12 19/12
5 �� 5
,_,O4 i
—
— Other Symbols
— IP 4 — it Indicates practical drill rig refusal.
10 0I48/12 10 Soil Lithology
— Ka — FILL,SAND,silty to clayey,gravelly,occasional cobbles and
� — boulders,slightly moist to moist,loose to medium dense,brown,black
Rom
— — .Aim SAND AND GRAVEL,slightly silty to silty,abundant cobbles and
15 15 t boulders,slightly moist,dense to very dense,brown,light brown
O;.
� �
Zi 1") _ - o
0 --
20 20
25 25
30 30
35 35
— - NOTES:
1. The test hole was drilled on October 17,2019 with 4-inch continuous
— — flight auger.
2. Test hole descriptions are subject to explanations contained in this
— report.
40 40
LOGS OF EXPLORATORY BORINGS
Project: Project No.:
RoEngineering 1040 & 1050 Matchless Drive 19-038G-G1
&Consulting, Inc. Aspen, Colorado Figure 2
RJ Engineering & Consulting, Inc.
Summary of Laboratory Test Results
Project No: 19-038G-G1 Project Name: 1040 & 1050 Matchless Drive, Aspen
Sample Location Grain Size Analysis Atterberg Limits Water Swell (+)/
Moisture Dry •Gravel Fines Soluble Consoli-dation
Test Sample Content Density Sand LL PL PI Description
Depth (ft) o >#4 0 (%) (%) (%)
<#200 Sulfate (-)at 1,000 psf
Hole Type (/o) (pcf) (%) (/o) (%) (%) (%)
TH-1 4 CA 13.9 108 29 FILL, sand, silty to clayey
9 CA 7.2 126 16 36 25 11 SAND, gravelly
TH-2 4 CA 7.2 120 22 NL NP NP FILL, sand, silty to clayey
•
•
•
*Laboratory testing by others
CA-Indicates modified California sampler
NL-Indicates non-liquid /]
NP-Indicates non-plastic Page 1 of 1 �/
THP ISOLATrY1 ® ROW
INTRODUCTION
An important component of any Stormwater Pollution Prevention
Plan is inspection and maintenance.The StormTech Isolator Row is
a technique to inexpensively enhance Total Suspended Solids(TSS)
removal and provide easy access for inspection and maintenance. ,;llf
THE ISOLATOR ROW
The Isolator Row is a row of StormTech chambers, either SC-160LP,
SC-310, SC-310-3, SC-740, DC-780, MC-3500 or MC-4500 models,
that is surrounded with filter fabric and connected to a closely located
manhole for easy access.The fabric-wrapped chambers provide for Looking down the Isolator Row from the
hown
settling and filtration of sediment as storm water rises in the Isolator manholee enopening,
the ,woven geotextile is se.
between the chamber and stone base.
Row and ultimately passes through the filter fabric.The open bottom
chambers and perforated sidewalls(SC-310, SC- 310-3 and SC-740
models)allow storm water to flow both vertically and horizontally out of
the chambers. Sediments are captured in the Isolator Row protecting -
the storage areas of the adjacent stone and chambers from sediment
accumulation.
Two different fabrics are used for the Isolator Row.A woven geotextile i..
fabric is placed between the stone and the Isolator Row chambers.
The tough geotextile provides a media for storm water filtration and
provides a durable surface for maintenance operations. It is also r
designed to prevent scour of the underlying stone and remain intact
during high pressure jetting.A non-woven fabric is placed over the
•
chambers to provide a filter media for flows passing through the - ,
perforations in the sidewall of the chamber.The non-woven fabric is not
required over the SC-160LP, DC-780, MC-3500 or MC-4500 models as
these chambers do not have perforated side walls. StormTech Isolator Row with
The Isolator Row is typically designed to capture the"first flush"and Overflow Spillway(not to scale)
offers the versatility to be sized on a volume basis or flow rate basis. OPTIONAL
An upstream manhole not only provides access to the Isolator Row but PRE-TREATMENT
typically includes a high flow weir such that storm water flowrates or
volumes that exceed the capacity of the Isolator Row overtop the over STORMTECH
ROW
flow weir and discharge through a manifold to the other chambers.
The Isolator Row may also be part of a treatment train. By treating IN
FOAVIEMETat
MANHOLE
storm water prior to entry into the chamber system,the service life can WITH ,w1111vv1
be extended and pollutants such as hydrocarbons can be captured. OVERFLOW
=
Pre-treatment best management practices can be as simple as =M.
deep sump catch basins, oil-water separators or can be innovative = =
ECM �
storm water treatment devices.The design of the treatment train and CENTRIC = ;--a
selection of pretreatment devices by the design engineer is often HEADER =
driven by regulatory requirements.Whether pretreatment is used or not, =MR+
the Isolator Row is recommended by StormTech as an effective means =ME.
to minimize maintenance requirements and maintenance costs. _ =MB-
Note: See the StormTech Design Manual for detailed information on
designing inlets for a StormTech system, including the Isolator Row. OPTIONAL
ACCESS STORMTECH CHAMBERS
THE MOST ADVANCE NAME IN WATER MANAGEMENT SOLUTIONS'M
2
_r ISOLATOR ROW
..4%, A.. ----r
INcPFCTION/MAINTENANCE
INSPECTION
• 11 / The frequency of inspection and maintenance varies by location.A
1 routine inspection schedule needs to be established for each individual
location based upon site specific variables.The type of land use(i.e.
-
or
industrial, commercial, residential), anticipated pollutant load, percent
O
pp ` imperviousness,climate, etc. all play a critical role in determining the
I actual frequency of inspection and maintenance practices.
At a minimum, StormTech recommends annual inspections. Initially,
the Isolator Row should be inspected every 6 months for the first year
of operation. For subsequent years,the inspection should be adjusted
based upon previous observation of sediment deposition.
The Isolator Row incorporates a combination of standard manhole(s)and strategically located inspection ports
(as needed).The inspection ports allow for easy access to the system from the surface, eliminating the need to
perform a confined space entry for inspection purposes.
If upon visual inspection it is found that sediment has accumulated,a stadia rod should be inserted to
determine the depth of sediment.When the average depth of sediment exceeds 3 inches throughout the length
of the Isolator Row, clean-out should be performed.
MAINTENANCE
The Isolator Row was designed to reduce the cost of periodic maintenance. By"isolating"sediments to just
one row, costs are dramatically reduced by eliminating the need to clean out each row of the entire storage
bed. If inspection indicates the potential need for maintenance,access is provided via a manhole(s) located on
the end(s)of the row for cleanout. If entry into the manhole is required, please follow local and OSHA rules for a
confined space entries.
Maintenance is accomplished with the JetVac process.The JetVac process utilizes a high pressure water
nozzle to propel itself down the Isolator Row while scouring and suspending sediments.As the nozzle is
retrieved,the captured pollutants are flushed back into the manhole for vacuuming. Most sewer and pipe
maintenance companies have vacuum/JetVac combination vehicles. Selection of an appropriate JetVac nozzle
will improve maintenance efficiency. Fixed nozzles designed for culverts or large diameter pipe cleaning are
preferable. Rear facing jets with an effective spread of at least 45"are best. Most JetVac reels have 400 feet
of hose allowing maintenance of an Isolator Row up to 50 chambers long.The JetVac process shall only
be performed on StormTech Isolator Rows that have AASHTO class 1 woven geotextile(as specified by
StormTech)over their angular base stone.
StormTech Isolator Row(not to scale)
Note:Non-woven fabric is only required over the inlet pipe connection into the end cap for SC-160LP,DC-780,MC-3500 and MC-4500 chamber
models and is not required over the entire Isolator Row.
OPTIONAL INSPECTION PORT
SC-]40 SC 310'COVER ENTIRE ISOLATOR ROW WITH ADS
GEOSYNTHETICS 601T NONWOVEN GEOTEXTILE ` Al Al' A.VIIIHOldffir00219HIONOW/H10110100/11HININ ArIODIE ®.
SC730'.8(2-4 m)MIN WIDE �,. 4u Ya3a
SC310'.5(1 5 m)MIN WIDE 1p& ``� " B.w T S at et S t:. �',05 ''?'9�H€tac4,+SwhFCnBt t.°$4E ^$B*$24 %$1 A� • V �'&T° $yaEgnsY t 2$-i i..
MC 4500 MC-3500,DC 780 SC 160LP;COVER PIPE I ��"n „�g,2{.qC�y. Ch q�Sl th 4�*$ e _ _ STORMTECH CHAMBER
CONNECTION N- OVENGEND WITH GEOTEXTILE
-I &� Y*1 Yet
GEOSVNTHETICS 601T NON-WOVEN GEOTEXTILE 5g g+$ q�Sogt*�<+a
p STORMTECH END CAP
CATCH BASIN ' ICI ^ III III 4410111 l III I
MAOOLE ( III'II II' III Olt�� 4 �I ICI1 I ' 1III'i'11 'III '
J mica� IiIIIII�',I,I''I°�II���III�, i � l lei 111IIIIYIII1!II I!I III�;I I�1I ( IIIII,! L
SUMP DEPTH TBD BY ' .. 1M,rog ',
SITE DESIGN ENGINEER
(24.[600 mm)MIN RECOMMENDED) TWO LAYERS OF ADS GEOSYNTHETICS 315WT WOVEN GEOTEXTILE BETWEEN
FOUNDATION STONE AND CHAMBERS,CONTINUOUS FABRIC WITHOUT SEAMS
1 24'(600 mm)HDPE ACCESS PIPE REQUIRED:MC-4500,MC-3500,SC-]40,DC-]80 10.3'(3.1 m)MIN WIDE:MC-4500
12'(300 mm)HDPE ACCESS PIPE REQUIRED'.SC-310 8.25'(2.5 m)MIN WIDE:MC
8"(200 mm)HOPE ACCESS PIPE REQUIRED:SC-160LP 5'(1.5 m)MIN WIDE:DC-780,SC-740
4'(1 2 m)MIN WIDE SC-310,SC-150LP
DS
ISOLATOR ROW STEP BY STEP MAINTENANCE PROCEDURES
STEP 1
Inspect Isolator Row for sediment.
A) Inspection ports(if present)
i. Remove lid from floor box frame
ii. Remove cap from inspection riser
iii. Using a flashlight and stadia rod,measure depth of sediment and record results on maintenance log.
iv. If sediment is at or above 3 inch depth, proceed to Step 2. If not, proceed to Step 3.
B)All Isolator Rows
i. Remove cover from manhole at upstream end of Isolator Row
ii. Using a flashlight, inspect down Isolator Row through outlet pipe
1. Mirrors on poles or cameras may be used to avoid a confined space entry
2. Follow OSHA regulations for confined space entry if entering manhole
iii. If sediment is at or above the lower row of sidewall holes(approximately 3 inches), proceed to Step 2.
If not, proceed to Step 3.
STEP 2
Clean out Isolator Row using the JetVac process.
A)A fixed floor cleaning nozzle with rear facing nozzle spread of 45 inches or more is preferable
B)Apply multiple passes of JetVac until backflush water is clean
C)Vacuum manhole sump as required
STEP 3
Replace all caps, lids and covers, record observations and actions.
STEP 4
Inspect&clean catch basins and manholes upstream of the StormTech system.
1)B) 2 1)A)
A
4 1
II1,1
I1 I11Iillillil�►�� ! iflil11111Ill
11
SAMPLE MAINTENANCE LOG
Stadia Rod Readings Sediment Depth
Date Fixed point to chamber I Fixed point to top of (1)_(2) Observations/Actions Inspector
bottom(1) sediment(2)
3/15/11 6.3 f t InoNe New 41nsEalLQElotn, 4Xed poilnE is CI frame aE 'DOM
grade
9/24/11 6.2 0,1 f E Some 9ri,E f eLE SM
6/20/13 5,$ 0,5 fE Mucky feel, debris visible iln manhole alnd LK NJ
IsolaEor Row, maiinEeinalnce due
_7/7/13 16.3 f E 0 System jetted alnd vacuumed 1 D3M
Allidlim-
4 ADS"Terms and Conditions of Sale"are available on the ADS website,www.ads-pipe.com
The ADS logo and the Green Stripe are registered trademarks of Advanced Drainage Systems,Inc. StormTech® 11.1 .41
Stormtech®and the Isolator®Row are registered trademarks of StormTech,Inc.
®2017 Advanced Drainage Systems,Inc.#11011 03/17 CS Delen(ion•Relention•Wakr Oual?y
A division of EKE.
Advanced Drainage Systems,Inc.
4640 Trueman Blvd.,Hilliard,OH 43026
1-800-821-6710 www.ads-pipe.com