Hermosa Vista & Hawes Road Storm Drain and Basin

The design used the existing detention basin constructed as part of the Madrid subdivision as an online facility that outlets to a storm drain discharges to Culver – Hawes Basin. During the pre-design study, the Madrid online basin bypass was optimized to mitigate existing flooding of the downstream subdivision. The Culver-Hawes Basin is an off-line facility where low flows bypass the basin. The design included the development of an SWMM model to verify the dynamic operation of the off-line basin diversion structure. The Hawes and Hermosa Vista storm drain downstream of the basin conveys the flood flows to the Spook Hill Floodwater Retarding Structure. The system is designed to convey the 100-year flood and includes approximately 2.5 miles of large-diameter storm drain and a 25-acre foot detention basin. The project also had landscape and aesthetic treatments, PAAC, and public meetings.