Title
Consider and take action on a resolution authorizing a professional services agreement with Dannenbaum Engineering Corporation (DEC) for design work related to the Dove Meadows & Borden’s Gully Detention Pond Project (DR1903) in an amount not to exceed $255,500 (Director of Engineering)
Background:
Approval of this resolution, will authorize the City Manager to enter into an agreement with DEC to design an approximate 115 ac-ft detention pond and related drainage improvements within the Dove Meadows Subdivision and along Borden’s Gully for an amount not to exceed $255,500.
In the aftermath of the Hurricane Harvey flooding, City Staff began working with DEC to conduct a Hydrologic & Hydraulic (H&H) Study of areas within the Magnolia Bayou and Borden’s Gully Watersheds. A contract was executed with DEC in February 2018. On November 29, 2018, City Staff and DEC held a public meeting to go over the preliminary findings of the study and to discuss potential improvements to help reduce flooding within this area. One of the areas of concern discussed during the public meeting was the drainage within Borden’s Gully and the lack of a detention pond for the Dove Meadows Subdivision. Due to limitations with the existing box culverts at Hughes Ln and Deats Rd, Borden’s Gully could not drain efficiently which in turn can push water back into the subdivisions detention ponds and drainage systems which can occur during 1% exceedance rainfall events. Since Dove Meadows was constructed prior to the City having detention requirements and is the closest subdivision within the City to the restrictions at Hughes Ln and Deats Rd, they experience street and structural flooding sooner than other areas that drain into Borden’s Gully.
Based on DEC’s study, City Staff created a potential drainage improvement project. This project was included as part of a list of potential drainage projects outlined on the City’s recently passed May 2019 General Obligation Bond Referendum.
For this Professional Services Agreement, DEC will provide engineering services for drainage improvements, specifically an approximate 115 acre-foot detention pond along Borden’s Gully as well as a review of the Dove Meadows drainage system so that if possible, modifications can be made to allow a portion of the subdivision’s drainage system to flow into the detention pond reducing the potential for structural inundation within the subdivision during 1% exceedance rainfall events.
The Construction Cost for this project is estimated at $2,712,000. The project is estimated to take approximately 3 years to complete (Design, Permitting, Land Acquisition, and Construction). In addition to the design and construction costs, it is anticipated that the City will need to acquire easements and Land for the successful completion of this project.
Attachments:
1. Data Sheet
2. Proposed Resolution
3. DEC Professional Services Agreement
4. Aerial Map
CONTRACT ORIGINATION: Reviewed and approved by the City Attorney's Office
FUNDING
{X} Funds in the amount of $255,500 are available from Miscellaneous Capital Projects Fund 5015 with expenses charged to DR1903-PLANDESIGN-DESIGN-TS CASH. The design cost will be funded by the GO Bond sale and Misc Capital Projects Fund 5015 will be reimbursed once bond proceeds are received.
{X} Based on available cash flow, a Budget Amendment may be required to transfer from General Fund - Fund Balance to Misc Capital Projects Fund 5015. If needed, the transfer will be included on a future budget amendment for Council approval.
STRATEGIC PLANNING
{X} NOT APPLICABLE