Orange County Great Park Heart of the Park Lakes Design

Irvine, CA

PACE is providing conceptual planning, design, and permitting support for approximately 22 acres of lakes for the new Heart of the Park at Orange County Great Park. The lakes will offer numerous active and passive recreational opportunities while also serving as multi-functioning stormwater infrastructure for a 377-acre watershed. Divided into an Upper Lake and Lower Lake connected by a series of eight cascading falls, the lake area will be interspersed with boardwalks and viewing decks giving scenic views of the water. A water garden is proposed to be included in the Upper Lake to showcase wildlife and native plant life habitats while providing natural water quality treatment.

A pump station at the Lower Lake will contain all necessary treatment equipment, such as blowers, recirculation pumps, and alum and ozone injection. PACE is also designing aesthetic shoreline conditions and a lake liner to prevent water loss through seepage.

The lakes will function as the primary Best Management Practice (BMP) for the Orange County Great Park by capturing and detaining the park’s first flush stormwater. Since the lakes will be filled with recycled water, discharging stormwater mixed with recycled water is not desirable. Instead, mixed water will be directed back to the IRWD sewer system, where it can be treated and reused as recycled water. During large storm events, inflows will have the potential to discharge to downstream receiving waters, which is likely to require extensive coordination with regulatory agencies to abide by MS4 permitting and other regulatory requirements.

Key Features:

• 22 acres of manmade lakes
• Wetlands treatment with native plant life
• Recirculation pump system
• Stormwater detention and treatment
• Stormwater discharge permitting coordination