HomeMy WebLinkAboutDrainage Reports - 02/11/2019ADVANCED
-ENG I NEERING , LLC
July 23 , 2018
Ms. Beth Gulley
726 Laporte A venue
Ft. Collins, CO 80521
STRUCTURAL DRAINAG E D RAFTING
City of Fo Collins Approv d Plans
Approved by:~=:::::::B~::::::
Date: 3/, , / 2-0 19,
RE : Site Drainage at Parcel #9610400006 , Ft . Collins, Colorado
Advanced Engineering, LLC Project Number 3185-01-0lB.l
Dear Ms. Gulley:
We have consulted with you regarding a new custom home that is proposed to be constructed at the
above referenced site. The home is to have one story over a crawl space, with an attached garage
and shop. Our office has reviewed the existing and proposed drainage conditions at the site. This
review included visual observations at the site, review of a topographic elevation survey of the site ,
and area calculations . The purpose for this review was to evaluate the impact of the proposed project
on existing drainage conditions.
The site is 17.9 acres, predominantly native grass, and gently slopes to the southeast comer (the
Fossil Creek drainage). The home is proposed to be built in the north central portion of the site , at
the high side of the lot. A swale will be constructed around the north side of the home to direct
runoff away from the home. Beyond the home site, all flow will travel along existing natural
drainage paths across the lot in sheet flow through the native grasses, there will be no new point
sources of flow. All off-site flows that enter the lot will continue to flow across the site, as they have
historically. Please refer to our Drainage Plan, Project Number 3185-01-0lB, which shows our
recommendations for the swale and specifies an elevation for the top of foundation.
Based on our review, the area of the house and concrete parking pads and gravel driveway is less
than 3% of the site. This is far less than the 15% impervious area assumed by the Ft. Collins Master
Plan for the Fossil Creek Basin. Given this , it is our opinion the proposed construction will have a
negligible impact on existing drainage conditions. We feel the drainage will continue to function
as it has historically. We do not feel any mitigation or large scale grading of the site are needed.
The recommendations and conclusions presented in this letter are based on a review of the described
site, your plans and your directions. Our review was limited to the items described in this letter, and
is not intended to cover structural , mechanical, electrical, environmental, mold, or architectural
features of the site/buildings. Discrepancies or deficiencies revealed during construction should be
brought to the attention of the engineer. If you have any questions, please feel free to call.
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Sincerely, ~~~
Adva nced Engineerin ---::=-... ••~
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ADVANCED
ENGINEERING, LLC
S _TRUCTURAL DRAl~AGE DRAFTING
229 12TH aT. S.W, UJ'llll.AND, co B0537 F'HCINE 970-27&-1909
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