The World Reservoir Water Quality Improvements Plan
PACE provided engineering for water quality management and shoreline protection from wave run-up on a 720 ha (11,000 mu) reservoir serving as a focal point to a seven-star resort, The World. With manmade islands housing a Phil Mickelson designed golf course and the resort, good water quality in the reservoir is imperative. Historically, the reservoir has been plagued with poor water quality due to the water quality of the surrounding canals feeding the reservoir, which have worse than China’s Class V surface water quality standard. Also, during the dry season (May and June), salinity levels in the reservoir are approximately 0.8%.
PACE made recommendations regarding the lake layout and designed lake water treatment and circulation systems to promote consistently excellent water quality. The water quality treatment system consists of three stages; 1) Pre-treatment of canal water supplying lake, 2) in lake water quality management systems and 3) recirculation system located outside the lake with optional chemical and biological treatment systems. The pre-treatment system has a 27,000 m3 / day peak flow capacity with an 18 ha pre-treatment area including an equalization pond, activated sludge reactors, phosphate removal, clarifier basin, polishing wetland, UV disinfection and optional chlorination. The in-lake water quality management system includes deep and shallow zone aeration systems, vegetated wetland filtration and a recirculation system. The exterior recirculation system was designed to prevent stagnation of water and includes six recirculation systems. An optional chemical / biological system was designed at each pump station to be used on an as-needed basis to address local water quality issues caused by changes to the source water conditions. Finally, a lake wave height and wave run-up evaluation was performed to analyze and address potential shoreline damage caused by wind and wave action. Wave run-up heights and fetch lengths were estimated for the reservoir and are being used to determine the necessary freeboard to prevent water from overtopping into the land areas.
PACE also designed water features on the golf course.
- Layout evaluation and recommendations to maximize lake / land value
- Lake water supply source treatment system
- In-lake recirculation, aeration and constructed wetlands at center of the lake
- Six exterior recirculation systems with optional chemical and biological treatment systems
- Lake wave height and fetch length analysis to determine minimum lake freeboard requirements