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This summer’s dry conditions have once again brought water supply to the attention of Maryland citizens. With Maryland facing a population increase of 1.1 million over the next 25 years, some citizens are asking, “Do we have enough water?” The answer to that question is complex and varies from region to region, however increasingly high treatment costs, a limited water resource in some areas, and aging infrastructure all combine to make water a commodity that we can no longer take for granted. As our population grows, water may no longer be available in unlimited quantities for every proposed use, but with careful management and proper planning, we can ensure a sustainable water supply into the foreseeable future.
As public water systems seek ways to ensure adequate supplies, they must look at both supply side management (increasing the amount of available water) and demand side management (decreasing the amount of water used.) Supply side management means developing new water sources, building additional water storage facilities, diverting water from one basin to another, or treating water that might not otherwise be potable (e.g. desalinization). These solutions are usually expensive, and may take many years to implement. Demand side management means reducing the amount of water that customers use, and can be accomplished through a variety of means. Water systems can usually implement demand side management programs relatively quickly and inexpensively.
There are many benefits to using demand side management. Using various approaches, water utilities can reduce water demands by as much as 20% - 50%, eliminate or postpone the need to build new treatment facilities, reduce operating costs, decrease the amount of water that needs to be treated at wastewater treatment facilities, and help meet the needs of current and future water customers. Their customers benefit from demand reduction programs, too. Water and wastewater fees may decrease, as will energy consumption. The Maryland Energy Administration estimates that about 20% of the energy use in homes is for heating water. The less water you use, the less money you spend to heat water. There are benefits for the environment, too. Reducing water consumption lessens the stresses that water withdrawals may have on water sources and the plants and animals that rely on adequate water flows in streams and rivers, and may also diminish the impacts of wastewater disposal on water sources.
Approaches to demand management for water utilities fall into three general areas: economic, structural/operational, and social techniques, and successful demand management programs usually combine these three approaches. Economic techniques involve providing monetary incentives or disincentives to encourage customers to reduce water use. On the incentive side, a water system might offer rebates to its customers for replacing older fixtures and appliances. A new toilet can use two or more gallons less per flush than an older unit, and the water savings from a toilet replacement program can be substantial. For example, the City of Tampa Florida installed 15,300 low flow toilets between 1993 and 1999, resulting in a water savings of .44 million gallons per day (mgd). That’s enough water to serve an additional 5,000 customers a day! Monetary disincentives can include restructuring of fees (i.e. making high water use more expensive) or imposing penalties or fines for customers who use water excessively or inappropriately.
Structural and operational techniques can include installing, upgrading, or repairing meters so that customers have an accurate assessment of their water use and are charged accordingly, implementing an aggressive leak detection and repair program, or providing retrofits for users. Social techniques are geared toward changing consumers’ behavior. Public education programs and residential water audits can provide citizens with the information and motivation to take the necessary steps to reduce water consumption in their homes.
Demand reduction is a viable and logical alternative to developing new water supplies. MDE encourages all water utilities to evaluate system demand and take steps to reduce water consumption. The first step for a water supplier would typically be to conduct a water audit that assesses the state of the water system and its users. An audit generally points to one or more areas where demand reduction techniques could be successful. MDE has published guidance for water utilities on conducting audits and implementing best management practices for water conservation. Click here for guidance documents.
There are many steps that citizens can take to reduce water consumption. Inside the home, check for leaks in pipes, fixtures, or appliances. Leaks account for about 8% of the water use in an average home. Replace older inefficient fixtures. An inefficient showerhead can use five or more gallons per minute (gpm), while a newer water-conserving showerhead uses only two and a half gpm. If appliances need replacing, be sure to seek out the most efficient ones. A new automatic dishwasher uses about seven gallons per load, while older models may use 14 gallons per load.
Outside the home, water savings can be even greater. Lawn watering uses enormous amounts of water. Consider eliminating lawn watering, or install a drip irrigation system, automatic timer, and/or water sensors to ensure that watering only occurs when and where it is needed. Water shrubs, plants, and flowers in the early morning or evening to reduce water losses from evaporation. Use a commercial carwash that recycles water for vehicle washing. Use a broom instead of a hose to clean sidewalks or patios. A typical garden hose uses four gallons per minute.
MDE encourages all citizens to actively seek ways to reduce their water use. Click here for more water conservation tips.
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