HomeMy WebLinkAboutCENTURY WIRELESS TELECOMMUNICATIONS FACILITY - FDP - FDP180022 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE RELATED DOCUMENTDrainage MEMO
Century, PDP170017
June 14, 2017
Page 1 of 2
5545 West 56
th
Ave, Unit E, Arvada, CO 80002 o) 303.566.9914
www.tepgroup.net
Water Utilities Engineering
City of Fort Collins
117 N. Mason Street
Fort Collins, CO 80524
(970) 224-6065
Subject: Drainage MEMO
Site: Century, PDP170017
620 Horsetooth Rd, Fort Collins, CO 80526
Summary:
The site “Century” located within parcel 9726379901 will consist of the construction of a
telecommunication facility, consisting of antennas and associated appurtencances on a proposed fifty-five
foot stealth bell tower, fenced compound & service equipment for future carriers. This is to be an unmanned
facility which will not require any water or sewer facilities, and traffic will consist only of maintenance
personnel, who will visit the site approximately twice a month. Refer to Zoning Drawings by TEP for a
complete reference.
Impervious Documentation:
For the consideration of the porosity of the ground areas that are changing, it is recognized that
unsurfaced areas are considered 100% pervious, graveled areas are 50% pervious, and concrete or asphalt
areas are considered 0% pervious. The following areas can be seen in the Planning Drawings by TEP.
• Atlas Tower plans to add a graveled, fenced compound with an area of 1,600ft2 which is considered
50% pervious.
• The existing dirt access drive is going to remain undisturbed from it’s original state. The portion
residing in the proposed Atlas Tower access easement is 1,606.8ft2 which is considered 100%
pervious.
• The foundation caissons of the tower are projected to be 37.7ft2 and considered 100% impervious.
• The brick wall foundation and remaining fence foundation piles are projected to be 81.4ft2 and
considered 100% impervious.
Given the areas as described above the total impervious area being added to the property is 859.55ft2 (0.0197
acres). This area is less than the 1,000ft2 benchmark of added imperviousness and therefore can forego storm
water detention, water quality and LID requirements.
Project Design:
The total parcel area is 5.55 acres. The existing impervious area on the property is 0.9962 acres
(17.9%). The area that the telecommunication facility is being built on is currently a dirt lot used for
temporary parking. The total area that will be disturbed during construction is 1,600 ft2. The total area that
Drainage MEMO
Century, PDP170017
June 14, 2017
Page 2 of 2
5545 West 56
th
Ave, Unit E, Arvada, CO 80002 o) 303.566.9914
www.tepgroup.net
will be disturbed will increase the total impervious area of the property by 859.55 ft2 (0.0197 acres)(0.35%).
Shrubs will be planted just outside the proposed fence perimeter for visibility improvement. All the
remaining area surrounding the compound will remain as dirt shown in the Zoning Drawings by TEP. The
existing amount of impervious area and gravel areas will not change by a significant degree that storm water
mitigation is recommended as a result of the construction. A silt fence is proposed to surround all disturbed
areas to control any potential sediment and runoff from polluting downstream water sources during
construction. The runoff from the proposed construction will not negatively affect nearby property owners.
Graham M. Andres, P.E.