By Angie Ziech
Last week the Environmental Law & Policy Center released part four of its four-part series “Land Use Tools to Protect Groundwater”, helping citizens of McHenry County, Illinois realize the value of shallow groundwater. Part 4: Water Efficiency Standards explores how water efficiency standards can be used to create new water supply. Part 1: Overlay Districts establishes the necessity of “overlay districts, Part 2: Preserving Recharge delves into the value of aquifer recharge, and Part 3: Conservation Design highlights the benefits behind conservation design.
Efficiency differs from conservation. Whereas conservation requires individuals to undertake a change in behavior, efficiency means simply doing more with what we have. This can be accomplished by technological improvements or other innovations. Efficiency may be better than conservation in the long term because behavior may be subject to an individual or a community’s circumstances and, therefore, may change in a manner that makes conservation less appealing.
Efficiency improvements are a cost effective way to expand water supply. If all households nationwide installed water-efficient fixtures, that would save more than 8.2 billion gallons of clean water each day! This quantity of water would fill 12,000 Olympic sized swimming pools and would add up to a cost savings of $18 billion per year. Efficiency also saves money by reducing the amount of energy we use to move water around to our homes and businesses. Electricity consumption could be reduced by 5 billion kWh if just half of American homes replaced inefficient water fixtures with more efficient models. Greater water security is another benefit of improved efficiency. Lowering water demand puts less pressure on existing water infrastructure, ensuring that these expensive investments last as long as possible. Reduced demand also helps water supplies last longer. Aquifers, lakes and rivers have more time to recharge and refill, ensuring their long term health and reliability to meet our water demands, even as communities grow.
Most importantly, developing efficiency often costs less than developing a new water supply. Efficiency upgrades cost about $0.46 – $1.40 per 1,000 gallons of water saved. Developing a new water supply source (by, for example, dropping a new well or building a reservoir) can cost 8,500 times more per 1,000 gallons… if it’s even an option! Efficiency may be the best way to expand water supply in areas like McHenry County, where there are few viable alternatives to the existing groundwater sources.
Communities should consider requiring at least all new residential development to meet a minimum level of water efficiency. More than half of water supplied is used by residences. Fortunately, almost all residences use the same kinds of water fixtures: toilets, faucets, showers, clothes washers and dishwashers. Outdoor water use can also be significant, especially during the dry months. A simple performance standard for all water fixtures can achieve huge water savings.
For indoor fixtures, there is already some consensus about high efficiency standards that several common fixtures and appliances are able to attain. For example, U.S. EPA WaterSense and Energy Star labels identify products with efficiency improvements over traditional models. The following are some standards for residential indoor water fixtures:
| Indoor Water Fixture | % Indoor Water Use | Efficiency Standard |
| Toilet | 27% | 1.28 gal/flush maximum |
| Urinal | 0.5 gal/flush maximum | |
| Showerhead | 17% | 2.0 gal/min |
| Faucet | 16% | 1.5 gal/min (bathroom)2.2 gal/min (kitchen) |
| Clothes washer | 22% | Energy Star models use 50% less water |
| Dishwasher | Energy Star models us a maximum of 5.8 gal/cycle |
Up to half of all water used for outdoor landscaping is wasted. Waste can be minimized by a number of possible efficiency standards for landscape development:
- Limits on the percentage of land that can be turf. For U.S. EPA WaterSense for homes, this is a limit of 40%.
- A requirement that the remainder of developed land be planted with native plants or plants that need little water.
- Requirements for irrigation systems to include moisture sensors and freeze gauges.
- Prohibiting irrigation systems from spraying on impervious surfaces.
- Separate metering for indoor and outdoor water use.
- Requiring a water use budget for developments.
There are two major ways to adopt water efficiency standards into local code and it is possible to adopt both. The first option is to adopt a stand-alone water efficiency code. For our region, the Chicago Metropolitan Agency for Planning has developed a Model Water Use Conservation Ordinance. Communities can adopt the ordinance as a whole or use only the sections that best suit their local needs. The other option is to amend the local building or plumbing code to include a section on maximum flow standards for plumbing fixtures. Major code development agencies such as IAPMO have examples of this type of code that can be integrated into existing code for indoor plumbing fixtures. A separate ordinance would be needed for outdoor standards. Communities may also consider whether existing developments will be required to retrofit to efficiency standards. Replacing inefficient toilets in older homes would save a tremendous amount of water. These retrofits could be a requirement if the property changes ownership, for example. The CMAP Water Conservation Ordinance can also be used as a model for this language.
Efficiency standards benefit the environment and the bottom line. Many resources are available for communities in our region looking for guidance on how to implement these standards. Water efficiency improvements are a common sense way to ensure that our region has a dependable source of water to meet our future demand.
