HomeMy WebLinkAboutExhibit A.1_Stream Margin Review Standards
Exhibit A.1
Stream Margin Review Standards
Staff Findings
Page 1 of 4
26.435.040.C, Stream Margin Review Standards
No development shall be permitted within the stream margin of the Roaring Fork River unless
the Community Development Director makes a determination that the proposed development
complies with all requirements set forth below:
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 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.
Staff findings: The floodway of the Roaring Fork River (Zone AE) and Zone X are depicted
on the Site Improvement plat. These areas represent the 100-year floodplain, based on maps
prepared by FEMA. Zone AE represents the area where water would rise and flow in a manner
consistent with the adjacent river during a 100-year flood. Zone X represents the area that
would be inundated by water during the same flood, but flow patterns would not occur. In other
words, Zone AE is more susceptible to dangerous flood patterns than Zone X, but both zones
remain vulnerable to flooding. After the opportunity to review the location of the 100-year
floodplain relative to the proposed locations of Building Envelopes “A” and “B”, staff does not
support memorializing building envelopes in the park. Future development in these areas
would continue to require Stream Margin Review and a No-Rise Certification. The findings
from those reviews have the potential to contradict the delineation established by a building
envelope and lead to an ambiguous outcome. Staff recommends that P&Z deny the request
to establish building envelopes.
Staff does support approval of Stream Margin Review to develop a permanent restroom facility
subject to the requirement that a No-Rise Certificate be obtained prior to building permit. Staff
also supports memorializing the proposed alternative Top-of-Slope. Staff finds that this
criterion is met to develop a permanent restroom facility and to memorialize the
proposed alternative Top-of-Slope. This criterion is not met for the request to establish
Building Envelopes “A” or “B”.
2. The adopted regulatory plans of the Open Space and Trails Board 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."
Staff findings: The impetus of this request originated from plans associated with the Open
Space and Trails Board of the City of Aspen Parks Department. Approving permanent
restroom facilities is consistent with these plans. The Park is heavily used, public facilities
are needed, and they should be provided in a safe and environmentally appropriate manner
to reduce risk of stream contamination. Memorializing an alternative Top-of-Slope is also
Exhibit A.1
Stream Margin Review Standards
Staff Findings
Page 2 of 4
consistent with the Open Space and Trails Plan as it will provide clarity for future
improvements that may be developed within this park. Staff finds this criterion to be met.
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 designated by this review and said envelope shall be
recorded on a plat pursuant to [Land Use Code Section26.435.040.f.1.
Staff findings: The work associated with developing a restroom will not impact any stream
bank vegetation or make any grade changes along the stream bank. Staff finds that this
criterion is met to develop a permanent restroom facility.
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.
Staff findings: The proposed restroom facility will comply with the City’s adopted stormwater
management standards. This will ensure that on-site drainage is accommodated on-site and
does not cause water pollution or other impacts on the Roaring Fork River. Staff finds this
criterion to be met.
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.
Staff findings: Alteration to the water course is not proposed within this application. The
proposed restroom facility is located a sufficient distance from the Roaring Fork River that
no water course will be impacted by the development. Staff finds this criterion to be met.
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.
Staff findings: Alteration to the water course is not proposed as part of this application.
Staff finds this criterion not applicable.
7. Copies are provided of all necessary federal and state permits relating to work within the
100-year flood plain.
Staff findings: The proposed location of the bathroom facility is located within the 100-year
floodplain. Pending approval of Stream Margin review for the restroom, a No-Rise
Certification will be required prior to building permit. Staff finds this criterion to be met.
Exhibit A.1
Stream Margin Review Standards
Staff Findings
Page 3 of 4
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. New plantings (including trees, shrubs, flowers and grasses) outside of the
designated building envelope on the river side shall be native riparian vegetation as
approved by the City. A landscape plan will be submitted with all development applications.
The top of slope and 100-year flood plain elevation of the Roaring Fork River shall be
determined by the Stream Margin Map located in the Community Development Department
and filed at the City Engineering Department.
Staff findings: Pending approval of Special Review to establish an alternative Top-of-Slope,
it will be clear where development will no longer be permitted in the future. Memorializing
this delineation will help ensure that future projects remain setback at least 15-ft. from the
Top-of-Slope. Staff finds this criterion to be met.
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 [Land Use Code Section 26.575.020 as shown in Figure "A"].
Staff findings: The proposed restroom facility will be setback more than 140-ft. from the top
of slope. The structure will not exceed 16-ft. in height. A condition of approval is included in
the resolution that requires representations to show the 45-dgree height limit is met at the
time of building permit. Staff finds this criterion to be met.
Exhibit A.1
Stream Margin Review Standards
Staff Findings
Page 4 of 4
10. 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 [Land Use Code Section 26.575.150]. A
lighting plan will be submitted with all development applications.
Staff findings: A condition of approval is included in the resolution that requires a lighting
plan to be submitted at the time of building permit (if lighting is proposed). The lighting plan
shall meet the provisions of Title 26 of the land use code. Staff finds this criterion to be
met.
11. There has been accurate identification of wetlands and riparian zones.
Staff findings: Based on the expertise and findings from the Engineering Department, the
Top-of-Slope helps to delineate the location of wetlands and riparian zones. The proposed
location of the bathroom will not impact these areas.
Staff finds this criterion to be met.