When we talk about the building sector’s impacts on climate change, most refer to energy usage and carbon emissions. But another factor sometimes overlooked is the increased need for water conservation. The UN Security General describes climate change as a “crisis amplifier,” and nowhere is that more evident in water supply in certain parts of the world. The UN Environmental Program has named water crises as one of the top global risks in the coming decade, as the number and duration of droughts globally have increased by 29 percent since 2000. This is not just a third-world problem, either. The U.S. Southwest, the hottest and most arid region in the nation, has been abnormally dry since 2012, according to the EPA, and drought periods are expected to become longer, more frequent, and more intense.
The two most prominent uses of water in the U.S. are for thermoelectric power and irrigation, but commercial buildings like offices use a fair share, as well. About 46,000 of the largest U.S. commercial buildings used 2.3 percent of the nation’s public water supply in 2012, according to a study by the U.S. Energy Information Administration. That doesn’t sound like a lot, but 2.3 percent represented about a billion gallons of water used per day. Helping to conserve water as a building owner is a laudable aim to protect the environment, and in certain parts of the U.S. Southwest, noncompliant buildings may even face mandatory conservation measures.
But water conservation in office buildings goes beyond being eco-friendly. Inefficient water use can also get very expensive, leading to exorbitant utility bills for property owners at a time when water rates continue to rise. The average annual price escalation for water from U.S. utilities was 4.1 percent between 2008 and 2016, according to the Department of Energy. Some regions and specific utilities had much higher price hikes, though. For example, the Northeast and Midwest have some of the lowest national water utility prices, but they increased annually at 8.6 percent and 6 percent, respectively, between 2008 and 2016. And in cities like Naperville, Illinois, customers saw staggering annual rate increases of 15 percent during those years. This has led to multiple investigative reports claiming water utility bills are becoming too expensive for some homeowners and renters, but it can sting commercial property owners, too.
Water bills are surging nationwide because utilities need the revenues to replace aging infrastructure like corroded pipes and overflowing sewer systems. The EPA estimates the U.S. needs to spend about $665 billion over the next 20 years to upgrade water and sewer systems, repairs that water companies have put off for years to keep prices low. This gave many of us the expectation of cheap water for decades, but that could be changing now. Utilities depend heavily on customers for revenues and get just four percent of their funding from the U.S. government. Some utilities out west, like in Los Angeles, also cite drought concerns and loss of revenue as reasons for rate hikes. But for the most part, water availability hasn’t impacted utility rates, it’s more so tied to infrastructure improvements and operating costs.
Savvy property owners have saved water through various means over the years, most of the gains come from targeting restrooms. Restrooms use the most water in the average office building at 37 percent, according to the EPA, followed by heating and cooling (28 percent) and irrigation for landscaping (22 percent). Addressing water waste in restrooms is low-hanging fruit that involves replacing older-model toilets, faucets, and other fixtures with higher-efficiency ones. WaterSense labeled restroom fixtures use 20 percent less water than standard models and provide short payback periods.
Another sneaky contributor to water waste are leaks. A toilet leak can waste 250 gallons of water per day for an estimated daily cost of $3.30, according to New York City’s Department of Environmental Protection. No matter how many high-efficiency restroom fixtures you install, ignoring leaks like this can wipe away a considerable portion of water savings. Keeping an eye out for leaks the old-fashioned way is one strategy, advising maintenance and housekeeping staff to be on the lookout and leaving signs in restrooms for occupants. Some property managers even designate a specific number to call to report leaks.
Water metering is a way to track usage and leaks, too, and it works best when incorporated into a building management system, so property managers and building owners can view the information on their dashboards.
Water audits are gaining popularity, though they don’t have the same widespread standardization of energy audits. Water audits can be done in-house or performed by a plumbing or utility professional. The benefits of the audit will be establishing more exact measurements of where water is being used in the facility and enabling a property owner to set benchmarking goals. For companies with multiple facilities, this can be especially helpful, as you’ll be able to compare and contrast performance between buildings. Diving deep into the data, property owners can also prioritize retrofitting projects based on ones that’ll have the most impact.
Mechanical equipment for heating and cooling is another huge source of water consumption. Keeping cooling towers clean and minimizing scale build-up is one way to reduce HVAC water usage. Property owners can also offset the total potable water needed for cooling tower systems by using ‘free water,’ or condensate generated by air handler and fan coil units. Condensate is naturally generated when humid air passes over cold coils in air handler units and, by recovering this condensate, EPA says facilities can send significant amounts of it back into cooling towers. Hyatt Regency Atlanta tried this, and the payback period for the $12,000 condensate recovery system was just six months. EPA’s case study on the hotel added that it is considering using a rainwater harvesting system to use captured rainwater to further offset potable water demand in cooling towers.
Upgrades to irrigation systems are another area to target. Experts recommend using drip irrigation rather than traditional sprinkler systems and using drought-tolerant native plants more often, which require less water to flourish. Rain detection or soil moisture sensors can trigger building automation systems so that when water meters detect wet periods irrigation systems don’t run. Beyond adding tech to water systems, regular inspections by groundskeeping staff can also do wonders. Many property owners are surprised by how much water can be saved by conducting routine checks on broken sprinkler heads, repositioning sprinkler heads to provide adequate coverage, and looking for leaks.
Water conservation is a high priority for some commercial facilities in the U.S. facing climate-change impacts. Precipitation in the Southwestern U.S. was at its lowest level on record between January 2020 and August 2021, according to a report by the National Oceanic and Atmospheric Administration. The study warned that the extreme drought conditions are likely to worsen, leading to severe water shortages in reservoirs throughout the region. But even for facilities outside of those drought conditions, the rising rates of water utilities mean efficiency makes sense from a financial standpoint. Water utilities must replace aging treatment plants and pipe networks, and the costs are being passed off to residential, commercial, and industrial consumers.
Many property owners have likely already knocked off water-conservation low-hanging fruit in restrooms, such as replacing older toilets and fixtures with higher-efficiency WaterSense models. Going beyond those retrofits and developing a more comprehensive water efficiency plan could involve any number of upgrades, all of which lead to significant savings. New technologies like condensate recovery systems improve HVAC cooling tower efficiency and offer attractive payback periods and return on investment. More old-fashioned methods like regular leak inspections by maintenance, housekeeping, and groundskeeping staff can also have surprising results. No matter what options building owners try, water conservation will continue to be a big issue moving forward. Water waste in commercial buildings quickly adds up as an operating expense. Water efficiency isn’t just another sustainability goal, it’s great for your bottom line.