The following blog was authored by Sherwood Designer, Jessica Stanley.
The South Lawn and Visitors Center Pavilion phases of Orange County Great Park are complete! This project hits home for me as it is the first built project that I have designed and lead the construction administration process for at Sherwood! Woohoo!
The park opened the sport and fitness complex on September 21st by hosting the “Great Summer Games” for the community and we just gave the official certificate of completion letters to the City. Sherwood Design Engineers was the Engineer of Record for both phases and worked alongside WRNS Studio and Bellinger Foster Steinmetz (BFS) Landscape Architects on the 30 acre expansion of the public open space.
The South Lawn includes four new soccer fields, two of which are synthetic turf, giant chess boards and outdoor ping ponds tables, a walkable “timeline” which allows visitors to read about the significant historical events while walking throughout the park, and a very advanced stormwater collection and reuse system. The design of the stormwater management system was the highlight of Sherwood’s work on the project.
The park was required to meet new, strict, regulations for stormwater management that encourages retaining all stormwater on site. The park also set high sustainability goals for net reduction of water use on site. The project meets these regulations and guiding principles by harvesting rainfall from the site and reusing it as irrigation for the park.
The system has six ponds, with a total volume of approximately 6 million gallons. Stormwater is captured from the entire South Lawn project, but also from the North Lawn project and other off-site areas when there is capacity within the ponds to treat additional runoff. The stormwater conveyance strategy prioritizes surface conveyance to minimize pipe infrastructure which decreases costs and provides pre-treatment of the stormwater through landscape based filtration. In networks were stormwater is transported underground, the pipes outlet to bioretention benches around the pond perimeter to allow for pre-treatment. The pre-treatment, combined with aeration and circulation features, keeps the water features as clear and aesthetically pleasing as possible.
The pond system allows for additional treatment through a settlement treatment train- as water fills each pond it overflows to sequential storage areas. Water is then mechanically filtered and treated with UV disinfection for storage within two high water quality “amenity” ponds. These ponds act as both a water feature and as the final storage location before the treated rainwater is used for irrigation of the park.
The reuse system treats and reuses stormwater from the “Water Quality Design Storm” defined as the first ¾” of rainfall, which picks up the vast majority of pollutants and containments from the surface. It also supplies 55% of the South Lawn irrigation demands. The remaining irrigation demands are met with municipal recycled water such that potable water demands on site are very limited.
The project has just been completed and already Frances Spivy-Weber, the Vice Chair or the California State Water resources Control Board called this project a “major breakthrough in cost effective stormwater capture and reuse.” It is also the winner of the 2013 Top Projects Award from the Stormwater Solution Magazine “the project combines multiple park amenities with green infrastructure, creating a sustainable space.”
Sherwood is very excited to have completed this project and is looking forward to seeing it at work this rainy season!