Title
Resolution to Petition the Washtenaw County Water Resources Commissioner to Design and Construct Stormwater Controls in the Allen Creek Drainage District in West Park to Improve Water Quality ($3,540,000.00 Project Amount; $3,401,940.00 City Share) (Roll Call Vote Required)
Memorandum
Attached for your approval is a resolution to petition the Washtenaw County Water Resources Commissioner (WCWRC) to undertake a project to design and construct stormwater controls in the Allen Creek Drainage District in West Park.
The Allen's Creek Initiative identified construction of stormwater control measures in West Park a priority to improve water quality within the creekshed during storm events. The Allen's Creek Initiative was launched in 2007 and is a collaborative effort with the WCWRC, the City of Ann Arbor, Ann Arbor Public Schools and the Allen's Creek Advisory Committee. Its goal was to identify, prioritize and select stormwater management projects on public lands that would reduce flooding and improve water quality in Allen Creek.
Much of Allen Creek is contained in underground piping that carries stormwater runoff from the urban core of Ann Arbor. Nearly 44% of the land draining to the creek is impervious and, as a result, stormwater frequently enters the creek too quickly, causing localized flooding during rain events. These rain events also carry pollutants from impervious areas to the creek, lowering water quality. Allen Creek falls within the Total Maximum Daily Load (TMDL) area of the Huron River. The goal of the TMDL is to remove 50% of the phosphorus and E. coli from storm water.
West Park provides drainage for approximately 783 acres of land in the creekshed. West Park currently has no stormwater quality control measures, so this project will provide those areas with needed stormwater controls that will improve downstream water quality. It is estimated that 229 lbs of phosphorous per year from the upstream drainage area will be removed from the creek as a result of the project. The project includes swirl concentrators, bioswales, mitigation wetlands, and a porous asphalt parking lot to reduce runoff and improve water quality. The resolution authorizes repayment to WCWRC for this project from the approved FY 2010 Storm Water Fund (Fund 0069) Operating Budget.
A formal petition from the City is required to move this project to construction. Allen Creek is an established Chapter 20 County Drain. Therefore, the work to construct the detention system and other control measures falls under the jurisdiction of the Washtenaw County Water Resources Commissioner. As an established drain, the costs of the project are assessed to the governmental entities within the drainage district area. The total cost of this project is estimated at $3,540,000.00. The County applied for a low interest (2.5%) State Revolving Fund (SRF) loan and American Recovery and Reinvestment Act (ARRA) funds to finance the project. WCWRC has received preliminary approval for the SRF loan. Final approval is conditional on this petition and award of construction. The City's apportionment of this drainage district is approximately 96.1% of the district. Therefore, the City's share will not exceed $3,401,940.00. If ARRA funds are secured, the cost of the loan and the City's proportionate share will be reduced by up to 40%.
As the Water Resources Commissioner will be assessing the City over a maximum of 20 years for this project, the City will not have to expend the full cost of this project at the time of construction. Rather, reimbursement to the WCWRC will be made over the financing period, with installments not to exceed $220,000.00 per year. The first payment is included in the approved Storm Water Fund operating budget for FY 10.
Staff
Prepared by: Molly Wade, Water Quality Manager
Reviewed by: Sue F. McCormick, Public Services Administrator
Approved by: Roger W. Fraser, City Administrator
Body
Whereas, There is a Total Maximum Daily Load (TMDL) for phosphorus and E. coli reduction within the Huron River;
Whereas, The Allen Creek Drainage District is within the area covered by the phosphorus and E. coli TMDLs;
Whereas, The Allen's Creek Initiative has identified the construction of stormwater improvements in West Park as a priority to improve downstream water quality;
Whereas, The City Council intends to file with the Water Resources Commissioner for Washtenaw County a petition to clean out, relocate, widen, deepen, straighten, extend, tile, interconnect, or otherwise improve a portion of the county drain located at West Park, known as the Allen Creek Drain pursuant to Section 482 of Chapter 20 of the Drain Code of 1956 (MCL 280.482);
Whereas, It is the desire of the City Council to have the Mayor and Clerk sign and file the necessary petition with the Washtenaw County Water Resources Commissioner; and
Whereas, A suggested form of such petition is now presented to the City Council;
RESOLVED, The City Council hereby determines to proceed with the proposed drain project for the Allen Creek Drain Drainage District as more fully described in the petition attached hereto as Attachment 1;
RESOLVED, The Mayor and Clerk be hereby authorized and directed to execute such petition for and on behalf of the City and to file the same with the Water Resources Commissioner of the County of Washtenaw;
RESOLVED, The City Council hereby consents to the location of the proposed clean out, relocation, widening, deepening, straightening, extending, tiling, interconnecting or otherwise improving a portion of the Allen Creek Drain within the limits of the City and the assessment of a portion of the cost of such improvements, so located, against the City; and
RESOLVED, That the assessment (approximately $3,401,940.00 plus interest) will be paid in twenty annual installments not to exceed $220,000.00/annually from the Stormwater Fund (Fund 0069) Operating Budget, beginning in FY10.