Lake Drive Storm Drain and Manchester Outfall Project

The City of Encinitas is advancing the Lake Drive Storm Drain and Manchester Avenue Culvert Outfall Project to address failing infrastructure and mitigate flood risks in a sensitive environmental area. The project involves replacing a 1,730-foot section of aging 48-inch corrugated metal pipe with new reinforced concrete pipe along the same alignment, extending from Lake Drive through an undeveloped canyon to Interstate 5, while also enhancing the Manchester Avenue outfall that discharges into the San Elijo Lagoon Ecological Reserve. At the Lake Drive site, construction includes a permanent detention basin to reduce flow velocity, a 25-foot-wide decomposed granite maintenance access road, and removal of temporary bypass piping installed under emergency permit. The Manchester Avenue site will undergo periodic sediment removal from the culvert and J-Channel to restore hydraulic capacity and protect downstream habitat, with removed material destined for approved landfills or beach replenishment locations under the City’s Sand Compatibility and Opportunistic Use Program. The sites lie within residential, open space, and ecological reserve zones, including the Multiple Habitat Conservation Program Focus Planning Area, requiring strict adherence to environmental protections and permitting processes including coastal development, conditional use, and design review permits. Construction must comply with Caltrans, ASTM, and City of Encinitas standards, including achieving 90% soil compaction per California Test Method 216-1978, proper pipe bedding per San Diego Regional Standard Drawing D-60, and strict trench safety protocols for excavations over five feet deep. Work is subject to restricted hours to avoid disturbance to nearby residences—no construction permitted weekdays from 4:00 PM to 7:30 AM or on weekends and holidays. The contractor must pothole all utilities prior to excavation, protect existing landscaping and property, and submit accurate as-built drawings upon completion. Inspection and acceptance are managed by the City of Encinitas, with formal acceptance occurring at the City Engineer's Office and inspections requiring 24-hour notice. Environmental compliance is central to the project, with mitigation performance standards mandating at least 60% native vegetation cover within four years and zero invasive perennials. All work must align with CEQA requirements and permits issued by agencies including the U.S. Army Corps of Engineers and the California Coastal Commission, with no federal contract clause or pricing data available in the materials provided. The project is subject to public review, with comments due by December 8, 2025, and is coordinated through city staff including the