It pays to fix dripping faucets. Water losses from leaks in water supply systems can range anywhere from 10% to 30% of the total water volume pumped. These losses occur in both modern and old water systems and in cities small and large. The water supply system of Mexico City loses enough water through leaks to supply Rome with all the water it needs!

If all the water supply and wastewater lines in New York City were laid out, they would stretch to California and back, twice (Figure 6.22). Keeping them in shape is a monumental task. In the 1970s, flows of water and wastewater in the New York City system began to exceed safety limits and push pollution maximums. In response, the city decided to conserve water.

174

First on their list of priorities was a public education campaign to inform water users of the need for, and means to achieve, conservation. The campaign included over 200,000 door-to-door informational visits, during which residents were offered free low-volume showerheads and a free leak inspection. In addition, the city offered rebates on low-volume flush toilets. Through this effort, the city eventually replaced over 1.3 million high-volume, conventional toilets—which use about 13.2 liters (3.5 gallons) per flush—with low-volume toilets, which use 6 liters (1.6 gallons) per flush. As a follow-up to the education program, the city installed water meters in all unmetered residences to help the city and individual residents track water use. Another major effort focused on detecting leaks in the water distribution system. The key to this effort was installing leak detectors on all the main water lines in the city.

New York City’s conservation efforts saved nearly 1.2 billion liters (320 million gallons) of water per day (Figure 6.23). Surprisingly, the greatest volume of water saved was associated with installing water meters in unmetered residences. It appears that when given the means to keep track, many residents reduced their water use.

Other municipal conservation programs around the world have resulted in impressive reductions in water use. From 1988 to 2013, water conservation efforts in Albuquerque, New Mexico, reduced daily per capita water use from 1,056 liters (279 gallons) to 560 liters (148 gallons). Meanwhile, the residents of Windhoek, the bone-dry capital of Namibia in southwestern Africa, decreased their consumption from 309 liters (82 gallons) to 196 liters (52 gallons) per capita per day (Figure 6.24).

While the results of these conservation efforts are impressive, water consumption in these three cities far outpaces that in the Republic of Singapore, a tiny, densely populated island faced with severe water constraints. Its 20 major reservoirs supply only half of its water needs, and it must purchase the rest of its water from nearby Malaysia. Consequently, it has focused its efforts on conservation and reduced per capita water consumption from 172 liters (45.4 gallons) per day in 1995 to 154 liters (40.7 gallons) per day in 2013. The Singapore water authority believes that further progress is possible and aims to reduce consumption to 147 liters per day by 2020 through its water conservation campaign. One suggestion made by the Singaporean Department of Environment and Water is for all residents to save water by reducing their length of showers by 1 minute.

Commercial and institutional buildings, including office buildings, hotels, commercial laboratories, and university buildings, are major users of water. Conservation efforts have produced large water savings and reduced operating costs in all these types of buildings. Of these, water conservation by hotels may be the best documented and the most familiar. The hotel industry is responsible for 15% of commercial and institutional water consumption in the United States. Three-fourths of hotel water use is for restrooms, laundry, landscaping, and kitchens. Faced with limited water supplies and increasing prices of water, the hotel industry has taken steps to be more efficient in their water use. A first step, as in private residences, has been to install more water-efficient toilets, showerheads, and faucets in guest rooms and to install more efficient laundry and dishwashing equipment. Another essential element in hotel conservation efforts is to encourage guests to conserve water by, for example, taking shorter showers and reusing bath towels. Hotels are also replanting their landscapes with more drought-tolerant plants and installing more efficient watering systems.

175

These efforts have produced impressive water savings. The Kalaloch Lodge in the Olympic National Park in Washington set a goal of reducing its water use by 40% by the year 2020. In addition to making its water system more efficient, Kalaloch Lodge issued a 5-minute shower challenge to guests and equipped all rooms with a timer set to 5 minutes. Their innovation paid off, producing a 46% reduction in water use between 2011 and 2014. Similarly impressive results have been achieved in large hotels in urban centers. For instance, by simply installing water-efficient fixtures, the 470-room Hilton Palacio del Rio Hotel in San Antonio, Texas, reduced its annual water use by 49% between 2004 and 2011. As a result, the hotel reduced its yearly water use by 26 million gallons and saved about $160,000 annually in water, sewer, and energy costs.