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BACKGROUND Caltrans is constructing a ramp metering project on Interstate 680, including areas in Pleasanton. This project will result in Caltrans connecting a 12-inch pipe to the City's storm drain system on the corner of Bernal Avenue and 1-680 to discharge stormwater runoff from 1.75 acres of 1-680 pavement. The State Water Resources Control Board has issued to Caltrans a National Pollution Discharge Elimination System (NPDES) Permit (Order No. 2012-0011-DWQ, as amended by 2014-0077-DWQ) that includes trash reduction obligations. Similarly, the RWQCB's MRP (Order No. R2-2015-0049), issued to municipalities within the state agency's jurisdiction including Pleasanton, requires permittees to achieve a 100% trash load reduction or no adverse impact to receiving waters from trash by July 2022. City staff negotiated with Caltrans to develop a Cooperative Agreement whereby Caltrans will provide the City with $300,000 for the construction of a full trash capture device to treat stormwater runoff from a 92-acre drainage area in the City consisting of mostly non-Caltrans Right of Way. In exchange, the City will manage Project design, implementation, and ongoing maintenance. Caltrans will benefit from this Agreement by earning compliance credit under their NPDES permit. The City will benefit by realizing a significant trash load reduction within city limits. DISCUSSION City staff and Caltrans have chosen a continuous deflective separator (CDS) or equivalent as the high flow capacity full trash capture device needed for this Project. CDS is a proven technology and on the State's list of Certified Full Capture System List of Trash Treatment Control Devices. Local jurisdictions, including Hayward, have had positive experience with CDS with respect to trash capture and ease of maintenance. In compliance with the MRP, the device will have a design treatment capacity of not less than the peak flow rate resulting from a one-year, one-hour storm, and trap all articles 5 mm or larger. The CDS will be installed within a 20-ft public service easement located at Koll Center. The device will replace an existing manhole approximately 100 feet from the 60-inch reinforced concrete pipe's outfall to Arroyo del Valle to the north. At this location, the CDS will treat runoff from approximately 92 acres of drainage basin encompassing most of Koll Center and some areas east of Valley Avenue and south of Bernal Avenue. The estimated cost for Project implementation is $300,000, with approximately $90,000 for purchasing the CDS unit and the remaining for design and installation. The City will invoice Caltrans within 30 days of execution of the Agreement for the full amount, and Caltrans will deposit $300,000 with the City within 60 days of receipt of the City's invoice. City staff will engage a consultant for Project design, including the preparation of specifications, plans, and cost estimates. In accordance with the Agreement, the specifications, plans, and estimates shall be completed within two years of the Agreement's effective date. Subsequently, staff will release a call for competitive bids to Page 2 of 3