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Water Conservation Toolbox: Benefits and Costs

Public water suppliers and water supply customers can accrue several benefits through water conservation. A few costs may too be associated with water conservation.

Calculate the benefits/costs of implementing specific conservation programs in your community*

1. Develop baseline projections of water use without conservation.
2. Estimate the affected population or number of accounts for each conservation measures. Multiply total population of the service area (accounts) by the projected population influenced by the measure, for each measure (market penetration times the installation rate) to determine who pays for the devices and to the measure's design, promotion, current use, applicable regulations, incentives and acceptability. Market penetration is the percentage of the population that receives the measure/message. The installation rate is the percentage of the population who actually install the device or implement the measure.
3. Estimate the total annual average and peak day water savings. Multiplying the affected population or accounts by the measure's unit water savings.
4. Estimate benefits. Multiply average savings in water, wastewater and energy by the utility cost savings. Utility cost savings could be based on the associated capital facility deferral savings (avoided costs) by reducing peak demands.
5. Estimate annual implementation costs. Costs to public suppliers include incentive costs such as those associated with rebates, staffing, auditor and field work, publicity, program implementation, effectiveness evaluation, and revenue loss. Costs to customers may include equipment and installation costs.
6. Compare costs and benefits.

 

Benefits**

• Reduced cost for chemicals and energy
• Improved local environment (instream flows, wetlands protection, topsoil preservation)
• Pollution prevention (reduced energy combustion by-products and chemical use)
• Reduced need for construction and operation of alternative supply systems
• Improved safe yield and pumping reliability in wells
• Reduced peak demand
• Smaller water supply facilities (reservoirs, storage tanks, wells, pumps, motors, etc.)
• Reduced operation and maintenance costs
• Reduced groundwater overdraft and contamination
• Improved long-term water utility revenue stability
• Reduced cost for water, sewer and associated electric and gas utility services
• Reduced costs for clothes-washing and dishwashing detergents
• Reduced size and extended septic system life
• Improved local environment (instream flows, wetlands protection, topsoil preservation)
• Pollution prevention (reduced energy combustion by-products and chemical use)
• Reduced runoff, soil erosion and costs for stormwater management
• Creation of distinctive, attractive properties
• Reduced use of and cost for lawn chemicals
• Reduced energy costs for landscaping maintenance
• Reduced air pollution and noise from gasoline-powered mowers and landscape equipment
• Extended life for lawn-mowing and equipment and irrigation systems
• Preservation of wildlife habitat and instream flows
• Reduced plant disease, rot and mortality caused by over watering

 

Costs**

• Resistance to changing outdoor water use habits
• Potential short-term water utility revenue instability and more frequent rate adjustments during the years when outdoor demand drops as a result of conservation
• Cost of any necessary renovation of existing plumbing, appliance, or related connections
• Change in water use habits
• Price of conservation device
• Costs to install device
• Increased time and care for maintenance during the transition from a conventional to a water-efficient landscape
• Difficulty accepting the look of low-water-use and native plans compared with water-intensive turf and exotic imported plants
• Potential reduction in business among conventional green industry product and service providers

*Source: Maddaus, William, Gwendolyn Gleason and John Darmody. Integrating Conservation into Water Supply Planning.

** Source: Vickers, Amy. Handbook of Water Use and Conservation. Amherst, Massachusetts, 2001.