Valencia Water Company Groundwater Softening Demonstration Project
About Valencia Water Company Investor owned utility regulated by the PUC More than 28,000 customer connections Serving approximately 100,000 residents Service area includes portions of the City of Santa Clarita and unincorporated L.A. County (Valencia, Stevenson Ranch, Saugus, and Castaic) Water Supply: Imported Water, Groundwater, Recycled Water
Valencia s Mission to provide reliable and quality service to our customers at a reasonable cost Regulatory compliance does not equal customer satisfaction
What is Hard Water? Hard water is water that has high levels of naturally occurring minerals (i.e., calcium) Hardness is measured as calcium carbonate Valencia groundwater has an average hardness of 450 mg/l Imported water has an average hardness of 122 mg/l LA DWP water has an average hardness of 120 mg/l
Hard Water Problems
10 Year Water Quality Complaint History Air 3% Health 12% Hard Water 36% Odor 21% ~50% Disinfection 5% Color 17% Taste 3% Turbidity 3%
How are Hard Water and Chlorides in the Santa Clara River Related? Hard water is a result of high levels of calcium in local groundwater Residents feel the need for softeners Chlorides are added to the waste stream through Automatic Water Softeners
Automatic Water Softeners Na + Na + Na + Na + Ca 2+ Ca 2+ Cl- Cl- Cl- Cl- Ca 2+ Ca 2+ Na + Cl- Na + Cl- Na + Cl- Na + Cl-
2005 Effluent Chloride Sources Infiltration 4% 5 mg/l Commercial 3% 5 mg/l Industrial 2% 3 mg/l Liquid Waste Disposal 0% 0.5 mg/l Residential (Non-SRWS) 16% 22 mg/l Disinfection 4% 6 mg/l Residential (SRWS) 35% 49 mg/l Water Supply 36% 51 mg/l 2005 SCVJSS Effluent Chloride Concentration = 142 mg/l Data provided by Los Angeles Sanitation Districts of Los Angeles County
Problems with Point-of-Use (POU) Water Softeners Add chloride to the waste stream Chlorides are not removed from water reclamation plants Too much chloride in water can damage agricultural crops by causing leaf burn or drying of leaf tissue Adds to consumer overall cost of delivered water
Work Completed To Date Pilot Study on Groundwater Customer Survey Softening Feasibility Study Membrane Filtration (Reverse Osmosis) Ion Exchange Pellet Softening
Pellet Softening Principles NaOH Hard Water Sand Soft Water Column filled with sand Add water up through column Raise ph to have calcium precipitate out Small footprint Reusable non-hazardous byproduct (white pellets) Fully automated operation Pellets
Benefits of Pellet Softening Aesthetics and Comfort No water spots Softer skin Environmental Benefits Reduced chloride discharge to SCR Reduced energy consumption Reduction in detergents and related compounds Reuse of byproduct (pellets) Enhance quality of recycled water Reduced cost to consumers
Chloride Reduction Source prevention is an environmentally superior and cost-effective alternative to end-of-use treatment! Hard Groundwater
Demonstration Project Area
2000 Chloride Concentration and Loading Profiles (Above Water Supply) Valencia Water Company Demonstration Site 80 Chloride Concentration (mg/l) 1600 1200 800 400 64 48 32 16 Chloride Loading (lbs/hr) 0 7/25/06 8:00 PM 7/25/06 4:00 PM 7/25/06 12:00 PM 7/25/06 8:00 AM 7/25/06 4:00 AM 7/25/06 12:00 AM 7/24/06 8:00 PM 7/24/06 4:00 PM 7/24/06 12:00 PM 7/24/06 8:00 AM 7/24/06 4:00 AM 7/24/06 12:00 AM 7/23/06 8:00 PM 7/23/06 4:00 PM 7/23/06 12:00 PM 7/23/06 8:00 AM 7/23/06 4:00 AM 7/23/06 12:00 AM 7/22/06 8:00 PM 7/22/06 4:00 PM 7/22/06 12:00 PM 7/22/06 8:00 AM 7/22/06 4:00 AM 7/22/06 12:00 AM 7/21/06 8:00 PM 7/21/06 4:00 PM 7/21/06 12:00 PM 7/21/06 8:00 AM 7/21/06 4:00 AM 7/21/06 12:00 AM 7/20/06 8:00 PM 7/20/06 4:00 PM 7/20/06 12:00 PM 7/20/06 8:00 AM 7/20/06 4:00 AM 7/20/06 12:00 AM 7/19/06 8:00 PM 7/19/06 4:00 PM 7/19/06 12:00 PM 7/19/06 8:00 AM 7/19/06 4:00 AM 7/19/06 12:00 AM 7/18/06 8:00 PM 7/18/06 4:00 PM 7/18/06 12:00 PM 7/18/06 8:00 AM 7/18/06 4:00 AM 7/18/06 12:00 AM Time of Day 0 Chloride Concentrations Above Water Supply (7/18-25/2006) Chloride Loading Above Water Supply (7/18-25/2006)
Demonstration Project Area Project area to receive same source of water (only softer) Community was built during the lift on softener ban Accessible location to install treatment
Demonstration Project Objectives Determine consumer acceptance of water quality improvements Optimize Treatment Process and Facility Layout Establish cost estimates and overall cost reduction to consumers Quantify chloride reduction in waste water