Laguna Creek Capacity Improvements

the i-880 crossing improvements are almost complete. cushing parkway crossing construction is ongoing. channel widening between 2,000’ downstream of cushing parkway has resumed in may and will be completed by december 2021. construction hours are mondays through fridays, between 8:00 a.m. and 5.00 p.m.

The Laguna Creek Capacity Improvement Project encompasses a series of flood control modifications along the channel between 2,000’ downstream of Cushing Parkway to Roberts Avenue upstream, designed toprovide Federal Emergency Management Agency (FEMA) standards for 100-year (one percent annual chance of occurring) flood protection to the adjacent communities. The active improvement projects under design and construction are located between 2,000’ downstream of Cushing Parkway and Auto Mall Parkway upstream. These active projects include channel widening between 2,000’ downstream of Cushing Parkway and Interstate 880 (I-880) Freeway; channel widening between Grimmer Boulevard and Auto Mall Parkway; crossing improvements at Cushing Parkway, Starboard Drive and I-880 Freeway. Details about the improvements planned at these locations are provided below. Channel Widening Between 2,000’ Downstream of Cushing Parkway to Starboard Drive, including Cushing Parkway Crossing Improvements Construction started in the summer of 2019 and is going into the third and final construction season this summer. The existing maintenance access roads are being lowered and floodwalls are being constructed along the District right-of-way lines to increase capacity and flow conveyance. An additional 12’ wide by 9’ high concrete box culvert is under construction to increase flow conveyance at Cushing Parkway crossing. The total project length is about 3,100’. I-880 Freeway Crossing The improvements at the I-880 freeway crossing are almost complete. Near the Fremont Boulevard and Cushing Parkway exit, two new 84” diameter culverts were installed under the freeway using a tunneling technique, one on each side of the existing triple box culverts. The project will allow more stormwater to flow under the I-880 freeway in Laguna Creek, reducing flood risk in the surrounding area. Channel Widening Between Starboard Drive and I-880 Freeway The existing maintenance access roads are being lowered and floodwalls are being constructed along the District right-of-way lines to increase capacity and flow conveyance. Design for this project is in the final phase. Construction is expected to begin in May of 2022 and completed by November 2023 (2 construction seasons). The project length is about 1,400’. Channel Widening Between Grimmer Boulevard and Auto Mall Parkway This project will involve widening the channel to increase capacity and flow conveyance, installing channel bank rock toe protection and vegetated soil lifts for bank stabilization, and reconstructing a maintenance bridge over the channel. Design for this project is underway. Construction is anticipated to begin in May of 2024 and be completed by November of 2026 (3 construction seasons). The project length is about 3,700’.

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