Item 13 - Agreement for Industrial/Commercial Inspections and NPDES Program Support Services

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Scope of Services and Schedule including automated delineations, refinement of drainages to include structures not reflected in digital elevation models (DEM), direct connection assessments, and modeling of land use trash generation rates (TGR). Direct connections are land areas that drain directly into the MS4 of the City or other jurisdiction, bypassing City municipal catch basins and any trash capture if Full Capture Systems (FCS) were installed at an inlet level. Because our GIS team's exceptional capabilities and understanding of the Trash Provisions policy and MS4 permit, and our previous history with the City, we will not have a "learning curve" related to tasks requested in this RFP. Trash Provisions support and GIS compliance work are a core business for our storm water group located in Orange County. Our team is uniquely qualified with an extensive work history for similar projects resulting in efficiencies and cost savings gained through years of experience. Our team also has extensive knowledge of the City's compliance strategy. We prepared the City's Trash Provisions Implementation Plan for the City that defined specific actions completed by City. The plan included current progress on program development, including mapped Priority Land Use (PLU) areas and modeled TGR adjustments, catch basin inlet delineated drainages, land use layer updates, preliminary land use substitution findings, and recommendations. The implementation plan is currently being updated for the remainder of the City and will include the projected trash load remaining. Based on current results, land substitution analysis suggests that FCS installed will achieve Track 1 compliance through submittal and acceptance of a land substitution request to the Santa Ana RWQCB and ongoing maintenance of the existing CPS devices. Delineation of Drainage Areas and Direct Connections The goal of this task is to: 1) identify City catch basins that receive runoff from PLUs and select equivalent Alternative Land Uses (ALUs); 2) provide more accurate ways to document runoff from City PLUS and areas that will be served by FCS to meet future annual report requirements; 3) confirm locations not captured by FCS requiring land substitution; and 4) obtain potential future OCTA grant funds (as part of the selection process). WSP has completed these delineations for several local clients, including the cities of Santa Ana, Irvine, Anaheim, Garden Grove, San Juan Capistrano, Laguna Beach, Laguna Niguel, Dana Point, and San Diego. Our approach includes automating the delineation process and performing a subsequent refinement. The initial task includes a desktop GIS analysis to develop a digital elevation model (DEM) based automated drainage delineation. This automated drainage layer saves time and provides a starting point for the subsequent refinement process. WSP recommends the subsequent refinement of drainages to account for structures that may affect drainage flow that are not reflected in the bare -earth DEM. In addition, the refinement process includes the search for public and private catch basins that may be missing in City GIS layers or need to be adjusted to match the location on aerial imagery. For the refinement process, WSP primarily uses storm drain infrastructure data, aerial imagery, and Google Earth street view images. Some drainage areas may require additional document reviews, such as the review of street improvement plans, private and public grading plans, and/or master drainage plans to complete the refinement process. City of Santa Ana I Industrial/Commercial Inspection and NPDES Program Support Services I Page 125 RFP No. 23-028