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Water Conservation. What is water conservation?. Any action, program or technology that: Reduces draw from water sources Reduces indoor and outdoor water use Reduces water loss or waste Improves efficiency of water use Increases water recycling/reuse Prevents water pollution.
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What is water conservation? • Any action, program or technology that: • Reduces draw from water sources • Reduces indoor and outdoor water use • Reduces water loss or waste • Improves efficiency of water use • Increases water recycling/reuse • Prevents water pollution
“Selling” water conservation to clients • What are some challenges to promoting WC planning to communities?
EPA Water Conservation planning tool for TA providers • Designed for systems serving populations of 10,000 or fewer • Specify conservation planning goals • Develop a water system profile • Prepare a demand forecast • Identify & evaluate conservation measures • Present implementation strategy ESEPA “Basic Guidelines for Preparing a Water Conservation Plan”
1. Specify Conservation Planning Goals • Goals should be specific and measurable • Examples: • Residential water use will be reduced by 15% over three years • Low flow showerheads will be installed in 20% of the residences by 2011 • Water audits will be completed on 30% of Commercial/industrial/institutional customers within the first two years
1. Specify Conservation Planning Goals (cont’d) • Planning goals may also include: • Eliminating, downsizing, or postponing capital projects • Extending the life of existing facilities • Avoiding new source development costs • Educating customers about the value of water • Protecting/preserving environmental resources • Lowering variable operating costs
2. Develop a water system profile • Summarize system characteristics • Population served • Service area • Annual water supply • Number of service connections • Water demand • Average day demand • Peak demand • Water pricing/rates
2. Develop a water system profile (cont’d) • Summarize system conditions • Designated critical water supply area? • Frequent supply shortages/emergencies? • Substantial unaccounted for/lost water? • High rate of population/demand growth? • Substantial improvements or additions planned?
2. Develop a water system profile (cont’d) • Summarize current conservation measures • What specific measures are in place? • When were they implemented? • How effective are they? • What are the estimated annual water savings from each measure?
3. Prepare a demand forecast • Based on anticipated population growth • More accurate if prepared for different classifications of water use • Residential • Commercial/large water users • 5 and 10 years forecasts • Optional if population is growing at less than 2% per year
4. Identify/evaluate conservation measures • Three level of conservation measures • Basic (even smallest systems should consider these) • Intermediate • Advanced
4. Identify/evaluate conservation measures (cont’d) • Criteria for selecting conservation measures can include: • Program costs • Cost effectiveness • Budgetary considerations • Ease of implementing • Staff resources & capability • Environmental impacts • Ratepayer impacts
4. Identify/evaluate conservation measures (cont’d) • Criteria for selecting conservation measures can include: • Water rights and permits • Legal issues or restraints • Regulatory approval • Public acceptance • Timeliness of savings • Consistency with other programs
4. Identify/evaluate conservation measures (cont’d) • Prepare a budget for each planned conservation measure, including estimated costs/gallon of water saved • Avoid counting water savings from a measure more than once when doing cost benefit analysis
4. Identify/evaluate conservation measures (cont’d) • Based on budget and other selection criteria, chose which measures will be implemented • Consider effects of conservation on system revenues (reduction in sales) • Include general summary of expected benefits, including effects on planned capital improvements
5. Present Implementation Strategy • Present strategy and timetable for implementation • Note specific factors or contingencies that might effect implementation • Address data collection and modeling required to track effects of conservation over time • Plan to update and revise WC plan
Indoor water use • For single family homes, average water use/person/day = 69.3 gallons (benchmark)
Indoor + outdoor water use • Total water use per person per day in the United States = 171.8 gallons From AWWARF “Residential End Uses of Water”
Review current and forecasted systems conditions • Exercise • Page 1-4
Definition of a Water Audit • Thorough examination of the accuracy of a water agencies records and control equipment • Overall Goal • Identify • Quantify • Verify Water Losses and Revenue • Performed Annually • To update the results of earlier audits
Water Audits • Water in: • Groundwater/surface water • Purchased water Total water in____________ • Water out: • Metered • Leaks/theft/under billing/ faulty control systems Total water out___________ • Water in – water out = unaccounted for water
“Selling” the benefits of a water audit to a utility • Reduced pumping costs (electricity) • Reduced treatment costs (chemical) • Increased revenues from undercharged customers • Increased knowledge of distribution system • Gain experience with the use of maps • Helps a utility respond more quickly to emergencies
Benefits of a Water Audit • Stretch existing supplies to meet increased needs • Defer construction of new facilities • Improved maintenance can reduced the likelihood of property damage • Better safe guard public health and safety • Cross contamination during system pressure loss occurrences
The health risks of a leaky distribution system • USEPA: The Potential for Health Risks from Intrusion of Contaminants into the Distribution System from Pressure transients • Potential for prolonged negative pressure events in distribution systems • Direct epidemiological connection between leaky mains/poor chlorine residual/ low pressure and gastrointestinal illness
Water Audit Activities • Verifying, Quantifying and Updating : • Water source inflow records • Inaccurate source data will invalidate the audit • Billing and accounting information • Un-metered use records • Parks, community centers, government facilities, firefighting
Authorized Un-metered Users • Un-metered uses must be carefully estimated to produce an accurate audit • Recommend metering all water users even if it is not billed
Water Audit Activities • Verifying and Updating system maps-GIS • Testing master and source meters for accuracy • Testing residential, commercial, and industrial sales meters for accuracy • Large meter testing is the most expensive item of a water audit ($150- $500 per meter, repair $350- $1000 per meter)
Tabletop Audit Exercise • Velo City
Water Board Faces Grand Jury Grilling Over Fatal Sink Hole Incident Officials “Turned a blind eye” to warning signs, alleges former manager. Story on page B2
Why Do Distribution Systems Leak? • Age • Corrosion • Faulty installation • Material defect • Excessive pressures (or surges) • Ground movement • Traffic loading and vibration
Where Is All This Water Going? • Leaks follow the path of least resistance • Porous (sandy) soil • Gravel backfill • Sanitary sewers • Storm sewers • Geologic features • A few actually reach the surface!
Are There Any Warning Signs? Many main breaks are actually unseen leaks that could be repaired before the break occurs
Robotic “Noise Loggers” • Placed in remote areas • Turn themselves on when noise is at a minimum (2 a.m.) • Listen for leak noises, then shut themselves off after a few hours • Transmit data wirelessly during daylight hours • Moved to other areas as needed
Leak Detection Technology • Portable contact (probe) devices • Unpowered geophones (stethoscope) • Amplified acoustic microphone systems • Multi-channel acoustic correlators • Portable noise loggers
Typical Equipment Cost • Portable contact (probe) devices - $1500-$2000 • Unpowered geophones - $30-$350 • Amplified acoustic detection systems - $2500-$3800 • Multi-channel acoustic correlators - $17,000 - $23,000 • Portable leak noise loggers - $200-$600 per unit depending on quantity
Equipment options • Purchase (good investment) • Rent / Lease • Hire a contractor • Borrow from neighboring agency • Vendor demo units
How Is A Leak Survey Done? • Map out a grid of water system • Experienced crew should cover 6 to 8 miles per day • Conduct preliminary survey using contact (probe) equipment • Return to pinpoint suspected leak locations using correlation
Water Conservation measures • Table 3
Public Education & Outreach • Understandable water bill • Usage, rates and charges • Information available on request • Brochures, etc. • Informative water bill • Conservation tips • Water bill inserts