Newport Dunes Lagoon Stormwater Diversion Concept Development

Newport Beach, CA


Under contract with the OC Public Works, PACE developed three preliminary stormwater diversion improvement options to improve the existing dry weather diversion system within the Newport Dunes – Hyatt Watershed to meet the fecal coliform TMDL . The three alternatives consist of a dry weather diversion system, dry and wet weather storage and diversion system, and a dry and wet weather treatment and diversion system to improve the water quality of the Lagoon and enhance stormwater runoff capture. The study was performed on three different tributary locations to the Newport Bay. Planning level engineering analyses/evaluations were performed in order to determine the conceptual facility requirements for the different alternatives, as well as planning level layouts of the facilities. Approximate construction cost and associated costs of construction were determined for each of the alternatives based on the conceptual facility requirements. A feasibility evaluation was performed to evaluate different levels of feasibility including performance, constructability, long-term maintenance, economics, and regulatory accessibility/permitting. The different alternatives were analyzed through a comparison evaluation process and then a specialized screening/ranking tool was used to select the most appropriate option for each site. A detailed technical memorandum was produced for each site detailing the feasibility evaluation process, the alternatives evaluated, and the recommended alternative.


Key Features:

  • NPDES Permit compliance
  • Stormwater quality improvement design
  • Retrofit of infrastructure for stormwater quality management within urban areas
  • Diversion structures
  • Water quality treatment
  • Retention/detention BMPs
  • Stormwater management basin
  • Dry weather runoff control
  • LID application
  • Customized treatment process
  • Low / high flow pump station design
  • Watershed analysis

OC Public Works Stormwater Program

Stormwater Management / Flood Control, Stormwater Quality