HomeMy WebLinkAboutFOX GROVE ODP - ODP130003 - REPORTS - DRAINAGE REPORTNo Text
of Boxelder Creek, and proposed revisions to the regulatory floodplain and floodway.
Due to land development market conditions at the time of the CLOMR, the project was
placed on hold. The project did not move to construction, and no LOMR was submitted
for the project.
The proposed Fox Grove site will drain into on -site detention ponds which will release into the
Boxelder Creek, located just west of the site. We do not currently propose any release to the
east. All water quality treatment requirements and LID requirements will be satisfied with the
proposed development. Means of providing for these requirements will be worked through at
the Preliminary and Final stages of the design process.
A portion of the subject property is encroached by the FEMA 100-year floodplain (Boxelder
Creek). FEMA FIRM Panel Number 1003 for Larimer County, Dated May 2, 2012 is referenced in
this study. Base (100-year) flood elevations in the vicinity of the proposed project range from
4920.0 to 4919.0 (elevations referenced to the City of Fort Collins NGVD 29). The project is
located outside of the 100-year floodplain but a portion of the project is within the 500-year
floodplain.
The Boxelder Creek floodway is located near the north and west boundaries of the property.
No fill is proposed within the floodway. Proposed grading will tie-in with existing grades
outside of the floodway boundary. Please see the attached FIRMette of the area. It is
acknowledged that the site design must satisfy the standards of Chapter 10 of City Code; Final
design documents will be completed accordingly.
In summary, this Overall Drainage Report letter adequately addresses any potential stormwater
changes associated with the proposed development. In general, there are no significant
changes proposed at a major drainage level. The ODP complies with the governing City of Fort
Collins Master Drainage Plans, and the previously approved drainage plans specific for the
subject property.
Please feel free to contact me with any questions you may have.
Sincerely
NORTHERN ENGINEERING
amox�
Aaron Cvar, PE
Project Engineer
N
ADDRESS: PHONE:970.221.4158
NORTHERN 200S.College.Ave.Suite.10 Ww.nort:
ENGINEERING Fort Collins, CO 80524 FAX: 970.221.4159 ww•norihernengineering.com
Overall Drainage Report.
Date: September 4, 2013
Project: Fox Grove
Overall Development Plan
Fort Collins, Colorado
Attn: Mr. Wes Lamarque
Fort Collins Utilities
700 Wood Street
Fort Collins, Colorado 80524
Mr. Lamarque:
This letter report accompanies the submittal for the Fox Grove Overall Development Plan
(ODP). Specifically, this letter report serves to document the overall drainage impacts
associated with the proposed Fox Grove Development.
The proposed development site is located southeast of the 1-25/Mulberry (State Highway 14)
interchange in Fort Collins, Colorado. The site is situated along the existing 1-25 east frontage
road, just south of the existing Interchange Business Park development. The overall Fox Grove
site is roughly 36 acres in size.
The proposed development site is in the City of Fort Collins Boxelder Creek Basin. Detention
requirements for this basin are to detain the difference between the 100-year developed inflow
rate and the historic 2-year release rate. However, if it can be shown by basin modeling that
undetained flows from the developed site would result in no increase in peak discharge within
Boxelder Creek, the detention requirement would be waived. No modeling has been done at
the present, but may be considered as this project progresses. The current submittal does
show proposed on -site detention.
Previous submittals for the Fox Grove site are briefly described below:
• CLOMR Request for Lee MLD, Northern Engineering, September 2007. This CLOMR
was submitted to FEMA in 2007 and approved in November 2008. The proposed work
shown with the CLOMR included both Lot 1(west of Boxelder Creek) and Lot 2 (east of
Boxelder Creek) of Lee MLD. The CLOMR included proposed grading along the east bank
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