BOARD00524

• Board Meeting Date: 7/28/2003
• Description: CF Section - Changes to Existing Loans - Weld County Tri-Area Sanitation District Regional Stormwater Detention Pond Project
• Board Meetings - Doc Type: Memo

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communities. Therefore, the communities of Dacono, Iirederick, Firestone, and Evanston have
consistently experienced severe flooding problems due; to storm water runoff from irrigated
farmlands in conjunction with runoff from developed areas. All these communities are partially in
the 100-year floodplain as defined by the Federal Emergency Management Agency.

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With significant population growth and development occurring within the District, the
District cooperated in the development of the 1-25 Corridol( Master Drainage Plan Godding Hollow
and Tri-Town Basins Weld County, Colorado Study, prepared by Anderson Consulting Engineers,
Inc. dated June 24, 1999. The master plan recommended that the existing detention facility
situated along the southern border of Frederick be enlarged: to act as a regional detention facility.

In the fall of 1999 the District hired the Sears-Brown Group, Fort Collins, Colorado to
prepare a feasibility study to construct a regional detention facility. The Sears-Brown Group
completed the feasibility study in January of 2000, which identified the construction of a 146 acre-
feet detention pond constructed over a 60 acre site adjacent to the Town of Frederick. Additionally,
the pond improvements involved the construction of upstream and downstream drainage channels
and various road crossing upgrades. These improvements in-place would remove the communities
from the Federal Emergency Management Agency regu1at~d 100-year floodplain.

Below is a brief summary of the major project elements and their estimated cost as
presented in the original cost estimate;

Detention Pond Excavation = $876,000
Detention Pond Embankment = $131,000
Inlet Pipe/Emergency Overflow = $40,000 .
Concrete Trickle Channel = $31,500
Outlet StructureIBox Extension = $90,000
Culvert from Sub-Basins = $12,000
Utility Relocations = $20,000
Revegetation = $42.000
Sub-total: = $1,243,100
20% Contingency $248,620
Construction Total: $1,491,720
Design, Surveying, Const. Eng. (15%) = . $223,758
Land Purchase = $350,000
Total Project Cost = $2,065,478

The regional detention pond work was bid for cqnstruction in the summer of 2002, and was
awarded to SEMA Construction (Contractor), at their bid price of $1,277,277.50. The Contractor
mobilized on-site in August of 2002 and is scheduled to ihave the project complete by September of
WOO. .

During construction of the project the District: encountered cost overruns, due to design
modifications, utility conflicts, and additional work added during the time of construction. These
additional costs are summarized as follows; .

Professional Enflineerinfl Services:

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The original cost estimate identified for design,i surveying, and construction inspection was
15% of the total cost of the project or $223,758. The District hired the services of Rocky
Mountain Consultants (Tetra Tech) to perform the design and construction inspection for the pond

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