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CC- Approval of a Third Amendment to the Existing Professional Services Agreement with Tetra Tech, Inc. for Additional Technical Support Services for the Culver Boulevard Stormwater Filtration/Retention Project, PR-002 (the “Stormwater Capture Project”) in an Amount Not-to-Exceed $8,405.
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Meeting Date: May 10, 2021
Contact Person/Dept: Sean Singletary/Public Works - EPO
Phone Number: 310-253-6457
Fiscal Impact: Yes [X] No [] General Fund: Yes [] No [X]
Public Hearing: [] Action Item: [] Attachments: []
Commission Action Required: Yes [] No [X] Date:
Public Notification: (E-Mail) Meetings and Agendas - City Council (05/05/2021);
Department Approval: Charles D. Herbertson, Public Works Director/City Engineer (04/27/2021)
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RECOMMENDATION
Staff recommends the City Council approve a third amendment to the existing professional services agreement with Tetra Tech, Inc. for additional technical support services for the Culver Boulevard Stormwater Filtration/Retention Project, PR-002 (the “Stormwater Capture Project”) in an Amount Not-to-Exceed $8,405.
BACKGROUND/DISCUSSION
On February 2, 2018, City Council approved a professional services agreement with Tetra Tech, Inc. for engineering design services in an amount not-to-exceed $515,920.
On September 23, 2019, City Council approved an amendment to the existing professional design services agreement with Tetra Tech for additional design services and construction engineering support services in an amount not-to-exceed $117,285 and authorized the Public Works Director/City Engineer to approve amendments to the agreement with Tetra Tech, Inc. in an amount not-to-exceed $11,728 for unexpected costs. These services also included providing grant required documents including a Monitoring and Reporting Plan and a Quality Assurance Project Plan (QAPP).
On January 11, 2021, City Council approved a second amendment to the existing professional design services agreement with Tetra Tech, Inc. for additional construction engineering support services in an amount not-to-exceed $50,485 and authorized the Public Works Director/City Engineer to approve amendments to the agreement with Tetra Tech, Inc. in an amount not-to-exceed $5,050 for unexpected costs. These services also included attendance at construction status meetings, review of contractor requests for information, extensive review of contract shop drawings, and review of various submittals for pump stations, electrical and instrumentation and miscellaneous submittals.
Stormwater Capture Project Scope of Work
The Stormwater Capture Project consists of a retention basin and filtration system to capture and treat stormwater/urban runoff from approximately 297 acres of drainage area. The Stormwater Capture Project utilizes this opportunity to construct a retention basin and a filtration system underneath the new landscaped median and bikeway between Sepulveda Boulevard and Harter Avenue which is part of the Realignment Project. A portion of the captured run-off is proposed to be stored in an underground retention basin and will be used to supplement the required irrigation for the proposed landscaping along Culver Boulevard. The excess captured run-off will be filtered and discharged back into the Harter Avenue storm drain downstream of the project as treated water. In addition, the Stormwater Capture Project was also designed to send captured runoff to Veteran’s Park for irrigation purposes. A dedicated wet well, pump system, and an irrigation supply line that will terminate at the cul de sac of Culver Blvd (North) will be constructed to convey captured runoff to Veterans Memorial Park for future irrigation use, thereby supporting the City’s water conservation efforts.
Technical Support Services
The City and Caltrans have begun discussion of a potential cost share for Caltrans’ drainage area that is treated by the project. In order to continue these discussions, additional water quality modeling analysis is required to determine design waste load reductions for various pollutants for the Caltrans right-of-way. The technical support services provided by Tetra Tech, Inc. include: tabulation of waste load allocation, total runoff volume and volume reduction, runoff concentration and concentration reduction and total runoff pollutant load for each land use type; waste load and volume reductions for the critical design storm; model input data, including drainage areas and representative pollutant concentrations assumed for different land use types; and meeting with Los Angeles Regional Board to discuss any proposed partnership with Caltrans. A third amendment to the Tetra Tech agreement is needed in order to cover these additional services.
FISCAL ANALYSIS
Funding for the Culver Boulevard Stormwater Treatment Project PR-002 in the amount of $8,405 for additional construction support services is available in account 434.80000. 730100.PR-002.
ATTACHMENTS
None
MOTION
That the City Council:
1. Approve an amendment to the existing professional services agreement with Tetra Tech, Inc. for additional technical support services for the Culver Boulevard Stormwater Capture Project, PR-002 (the “Stormwater Capture Project”) in an amount not-to-exceed $8,405;
2. Authorize the City Attorney to review/prepare the necessary documents; and
3. Authorize the City Manager to execute such documents on behalf of the City.