PRODUCING HIGH-QUALITY RECYCLED WATER FOR IRRIGATION OF THE PEBBLE BEACH, CALIFORNIA GOLF COURSES

摘要

In 1994, the Carmel Area Wastewater District, Pebble Beach Community Services District, Monterey Peninsula Water Management District, and Pebble Beach Company formed a public/private joint venture to produce and deliver recycled water for irrigation to seven golf courses in Pebble Beach, California, including world-renowned Pebble Beach Golf Course. Through this venture they began the Water Reclamation Project, which included tertiary treatment by sand filtration and chlorine disinfection. Shortly after start of operation of the new tertiary facilities, the Pebble Beach golf courses began experiencing some problems with the turf grass, particularly on the greens. This was discovered to primarily be the result of high sodium concentrations and high total dissolved solids (TDS) concentrations. To remedy the problem, the consortium, along with golf course superintendents, turf grass specialists, and Carollo, began the Salinity Management Project with the intent of improving the water quality and increasing the quantity of recycled water available for irrigation. As a result of early discussions, the turf grass water quality criteria was established and included limits of sodium concentration, Sodium Adsorption Ratio (SAR), and adjusted SAR, and ranges of electro-conductivity and pH. Microfiltration (MF) followed by reverse osmosis (RO) was selected to meet this water quality criteria. MF will also allow the treatment facilities to continue to meet the California Title 22 requirements for unrestricted use of recycled water. Much attention was also given to developing a control strategy to help minimize the operational complexity of the MF/RO system under the varying influent water quality and quantity. Several chemical feed systems, such as calcium hydroxide and gypsum, are also included to help meet the turf grass water quality criteria and to help stabilize the corrosive RO permeate.