Irrigation Demand Management

April 10, 2013

For many, a supply side approach is not much of an option. Rather, they are instituting demand side reduction programs–and in such sectors as agriculture, demand response programs–in an effort to achieve water efficiencies.

“I believe that the water crisis that’s unfolding before us–faster in some areas than others–will be very most likely solved through demand side management practices,” notes Trevor Hill, president and CEO of Global Water Resources.

Some technology is expensive and “tends to drive up the price of water, which in and of itself creates a very strong price signal, which has the real effect of driving down consumption,” adds Hill. “Sometimes it’s easier to start with price signals, which is the demand side management tool. The water crisis such as it is will be solved on the demand side with real-time data, price signals, and peer pressure with customers in how they rank against others in the same vicinity.”

Photo: Toro
Toro’s Precision Series Spray Nozzles and Precision Series Rotating Nozzles are commonly used in the West and Southwest.

That real-time data comes through technology that helps customers–as well as utilities–effectively manage their own behavior, Hill says. Such technology is so precise that it can help property owners know just how much water a lawn or plant needs.

Long Beach, CA, focuses on three factors in working to achieve demand management in irrigation: transforming grass lawns to water efficient landscapes, providing rebates and instituting water restrictions. The city’s largest effort, the lawn conversion program, is a long-term strategic measure intended to change the landscape norm from grass lawns to landscape that thrives in the semi-arid climate, says Matthew Veeh, director of government and public affairs for the City of Long Beach. The “Lawn-to-Garden” program provides $2.50 per square foot for turf that is replaced with draught-tolerant landscape appropriate to the climate.

Water restrictions prohibit against irrigating to the point of excess runoff and irrigating mid-day due to evaporation. Property owners must fix broken irrigation equipment such as line leaks or missing sprinkler heads. On the other hand, rebates are provided for technology such as weather-based irrigation controllers, rotating nozzles, and stream rotators.

“We will install, for a nominal fee, weather-based irrigation controllers at properties that have a lot of landscape; it’s cost-effective for us if they have a lot of landscape,” says Veeh.

In the use of the latest technology to achieve water efficiency, Veeh points out that it is particular to each property owner and the landscape size, financial considerations, and the extent to which they are willing to invest the effort.

Veeh is a fan of the Web-based irrigation controllers.

“I have five of them under my control, and I love these things,” he says. “They adjust themselves automatically based on weather in my city. I can adjust them up and down as I please.”

Long Beach installed 70 controllers throughout the local school district.

“For the first time in history, the guy in charge of the irrigation system knows what’s happening at every site,” says Veeh. “If anybody messes with his controllers, it sends him an e-mail. He has been able to dial down on a percentage basis so that the grass still looks decent, but it’s not lush. He’s been able to maintain the landscape being able to apply the minimal amount of water necessary, saving the school district a tremendous amount of money in the process–schools in California are under tremendous fiscal pressure. To me, that’s a really exciting technology.”

Long Beach also conducts indoor and outdoor landscape audits.

The city also maintains a website, which has been completely redesigned based on the results of a survey of water customers. It includes tips such as how to create an inexpensive draught-tolerant landscape, featuring photographs of attractive draught-tolerant landscapes.

“People tell us that the photographs are one of the most helpful things for them, in terms of having the confidence that they can do it and finding the kind of landscape that they would like for their yard,” says Veeh.

Long Beach offers 22 free landscape classes at a city site each year, plus a free online landscape class. For a nominal fee, a resident can request one of several local designers the city has on retainer for a consultation on visualizing alternatives to their grass lawn.

“It’s one of the most difficult things about getting rid of the grass,” says Veeh. “There’s nothing to design a grass lawn–you just put down sod or seed. To do something different, the options are infinite: big plants, little plants, different kinds of hardscape, different kinds of permeable material. A lot of people get so overwhelmed by the options.”

Direct mail is another aspect of Long Beach’s public outreach. Bill inserts are the most effective form of advertising and augment billboards, bus stop posters, and announcements in local cable TV and newspaper outlets. While Long Beach had started restricting watering days in 2007 because it was clear the city was on the verse of a water shortage, the restrictions were eventually revoked. Per capita water use dropped about 17%, and even though the water shortage is over, Long Beach has maintained a 16% per capita water use reduction.

“People realized they could dramatically cut back their water use, and their lawn didn’t die,” notes Veeh, adding that he hopes with a continuation of the city’s programs and public affairs, the water use reduction will be maintained.

Having the backing of the city’s board of water commissioners underscores the program’s success, Veeh points out.

“Our general manager reports to the board, which approves the budget, and hires and fires the general manager; so it’s not just an advisory board–it’s a real board–and they are enthusiastic supporters of conservation,” says Veeh. “That clears the path for us in our department. Our city council believes in doing what’s feasible in protecting our environment and to use our resources wisely.”

Veeh says he believes it’s important not to get heavy-handed in the approach to water efficiency.

“We believe that most people of Long Beach, if you just give them the facts, will come to the same conclusion that we have; so our extraordinary conservation education and messaging has really paid off,” he says.

Photo: City of San Diego Water Department
San Diego’s public outreach also includes a focused media campaign that includes Facebook sites, Twitter posts, bus and trolley wraps, light pole flags, bumper stickers on all city vehicles, a monthly e-newsletter, a poster contest, and a video contest.

If Veeh could change anything, it would be to see the landscape norm change at a faster pace.

“I understand people have lived decades thinking about nothing but grass lawns, and it’s hard to conceptualize something else,” he says. “There is a lot of work involved, a lot of cost, and people have busy lives. It’s a professional frustration to realize there are real-world constraints, but, nevertheless, you’re anxious to see bigger change than maybe is practical.”

That same program has yielded what Veeh considers the greatest success in Long Beach’s approaches.

“What surprised me the most is a lot of the customers who have joined our lawn and garden program have been incredibly enthusiastic. Last spring, we wanted to have a spring garden tour as another way of helping customers make the decision to go draught-tolerant and for them to get ideas and talk to people who have actually done it,” he says.

The city approached about 33 people who had completed their landscapes, hoping to get some of them to agree to host their site on the garden tour.

“All of them agreed to it, and some of them went out of their way to create a really pleasant environment for the tourists,” says Veeh. “They spent the whole day in their front yards talking to people, distributing literature, and showing people their landscapes and explaining the whole process to them–the cost, the labor, where they got plants, how to maintain it, how they killed their grass. I was very pleasantly surprised by the tremendous enthusiasm that a lot of these people have for what we’re trying to do.”

For its CII (commercial, industrial, and institutional) customers, Long Beach works with the Metropolitan Water District of Southern California, which offers a generic rebate program to regional water agencies.

“We add money to whatever the Metropolitan Water District is willing to put into a rebate, so we’ll add another $1 to the $3 offered for the rotating nozzles, for example,” says Veeh. “Met has a suite of about 12 different items for the CII customers.”

Since CII customers use water differently from residential customers, “rather than rebate everything possible, they do a proven water savings program where they can work with a customer and identify means of saving water.”

Then the customer can implement the program, prove that the water’s been saved, and they get a payment–a rebate–over that proven water savings.

“Long Beach has had its own proven water savings program for seven years, and now that Met has implemented its program, we are going to piggyback on that just like its normal rebate program,” says Veeh. “Met offers a certain amount of water savings through their program, and we’re going to add on top of that, so Long Beach CII customers will get an extra amount.”

When it comes to the energy water nexus, Veeh says while Long Beach doesn’t make energy conservation a big focus of the water conversation, “we definitely try to make people aware of it,” he says, adding that the topic is introduced through forums for CII customers, for example.

Veeh says he believes if a water agency isn’t charging a price where it is able to maintain its own infrastructure, then it is not charging the right price.

“In Long Beach, we certainly do that,” he says. “I think it’s a real frustration to the environmentalists, because they see environmental degradation in the source water in those watersheds, and they would like to see more money spent in those watersheds.

“We don’t have a pipeline to a watershed outside of our region,” he adds. “We buy water that’s imported by the

Metropolitan Water District. We can’t pay Met more than it charges, and we can’t charge our customers more than the cost of doing business. I’m really sympathetic to the idea that water is basically really inexpensive. We sell about four gallons for a penny, and with the economic downturn we believe that had some reduction in the per capita water use. We’d like to think that people are conserving because it’s the right thing to do as well, so people are sensitive to price and the pocketbooks.”

San Diego, CA, relies on imported water for more than 80% of its water supply.

“In recent years, we have experienced climatic and regulatory droughts,” notes JoEllen Jacoby, supervising landscape conservation designer for San Diego’s Water Conservation Program, an arm of the public utilities department.

One such drought extended from 2009 and 2011.

“In addition, competing forces for a limited supply means we cannot continue to expect an increasing supply of water for a growing population,” she adds.

Photo: City of San Diego Water Department
The City of San Diego utilizes smart irrigation technology as part of their demand management protocol.

The city also has passed a more restrictive ordinance against water waste that restricts watering times and runoff, says Jacoby.

Essentially, San Diego has had a water conservation program in place for more than 20 years.

The city offers programs and outreach that continuously affirms the need to conserve water. The city also offers surveys at no cost to residential and large irrigation customers providing feedback on their water use, items that need repair, and adjustments to their irrigation schedules. Additionally, rebates and incentives are offered through local and regional programs. Another feature of the program is a website, featuring a “watering calculator” and links to information on plant material and low water use landscape design.

“We participate in a regional landscape contest, offer classes on landscape topics, and participate in more than 60 public events where we promote water conservation in the landscape,” says Jacoby.

San Diego’s public outreach also includes a focused media campaign that includes Facebook sites, Twitter posts, bus and trolley wraps, light pole flags, bumper stickers on all city vehicles, a monthly e-newsletter, a poster contest, and a video contest.

“During our Level 2 restrictions, we had media spots on TV and radio, and a banner pulled behind a plane during heavy beach days,” says Jacoby.

The Level 2 campaign slogan was “No Time to Waste, No Water to Waste.” With the Level 2 campaign over, the current slogan is: “San Diegans Waste No Water.”

San Diego is a contributing member to the Water Conservation Garden that demonstrates appropriate irrigation and the use of low water plant material. The city also offers rebates for smart controllers, rotator nozzles, micro irrigation, turf conversion, and rain barrels. The city also has a discount coupon for low water use plants at nurseries. As a result of the city’s efforts, “our overall water use has gone down and our irrigation meter customers have been the leaders in water use reduction, indicating that water is being saved in the landscape,” says Jacoby.

“You can see a change in the plant palate as you drive around town. People are much more interested in changing their landscape.”

Irrigation technology used in San Diego to meet demand management goals includes smart controllers, rotator nozzles, drip irrigation, and in-line emitters. City parks–as well as public schools and universities–are incrementally being retrofitted to central control systems.

The energy/water nexus is a significant factor in irrigation demand management and is increasingly becoming part of municipal water conservation efforts, such as in San Diego.

“We always teach people that there is a water energy nexus, and the local power utility, San Diego Gas & Electric [SDG&E], has collaborated with us on several programs, including an irrigation water management program,” notes Jacoby.

“SDG&E has built a demonstration center for energy-efficient fixtures, and it showcases low-water use plants and micro-irrigation,” she adds. “Being at the end of the imported pipeline from the Bay-Delta and the Colorado River, it takes more energy to deliver water to San Diego, and thus, more energy is saved through water wise consumption.”

One of the challenges in implementing San Diego’s approach is “maintaining a continuing presence in the minds of our customers and changing the image of San Diego to a more climate-appropriate and less tropical landscape,” says Jacoby.

“Our current outreach campaign, San Diegans Waste No Water, reinforces this ethic and shows that the community is behind it, overcoming ideas that micro-irrigation is doomed to fail and that low water use means drab and ugly,” she says.

Part of demand management irrigation entails creating an environment that demands less in the first place. The Maximum Applied Water Allowance (MAWA), is a landscape water budget that provides 70% of the water necessary for high water use plants with a highly efficient irrigation system, says Jacoby. The MAWA can be achieved by a mixture of high and low water use plants and a mixture of irrigation delivery types or by a landscape that is completely moderate water use plants with a low-volume spray system, such as rotator nozzles. The budget varies based on the local climate as measured by the evapotranspiration (ETo).

“Based on the requirements of State of California law AB 1881, all new landscapes cannot exceed a Maximum Applied Water Amount of 0.7 x ETo x 0.62 x landscape area,” says Jacoby. “Grass is limited to 10% of the site for commercial sites. No grass in areas less than eight feet wide unless watered below grade. Additional requirements for separate irrigation meters have been imposed.”

Retrofits are not regulated but are encouraged through San Diego’s incentive programs, which are focused on the retrofit market, says Jacoby.

Cary, NC, has a comprehensive water conservation program that includes educational outreach initiatives, financial incentives, and regulations.

“The main incentive for customers to manage their demand is our increased block rate, or tiered rate structure, under which excessive irrigation will result in much higher unit water rates,” says Marie Cefalo, conservation program supervisor for Cary.

Cary’s focus is on residential customers, who comprise 70% of the demographics and volume of water used. Outreach is done through a comprehensive website, the “Beat the Peak” campaign, a fix-a-leak week campaign, free water audits, and grassroots outreach with block leaders. Since 1998, the town has held a multimedia “Beat the Peak” campaign to educate and remind customers about WaterWise irrigation practices as well as the ordinances–lawn enthusiasts play a game on the city’s website to save ladybugs from a leaky hose to win water-saving tools such as shut-off nozzles, hose timers, rain gauges, and soil probes as supplies last.

The driving factor for the programs was short-term capacity issues in 1996, but is now rooted in long-term water resource management. That long-term commitment to water efficiency as the best management practice as opposed to conservation as an immediate drought response has been an obstacle, Cefalo says. Nonetheless, there have been successes. Case in point: the average residential gallon per day/capita, adjusted for weather, has been reduced from 75 in 1996 to 57 in 2011. Overall water use in 2012 was 88 gallons per capita per day.

One of the hooks that Cary uses to attract people to the program is a turf buy-back program that’s been in effect since fiscal year 2009.

“It provides a financial incentive for our customers to reduce outdoor water use by removing turf and replacing it with either a warm season grass or a natural area,” says Cefalo. “We also offer free irrigation audits and will replace one zone with free precision spray nozzles.”

The town’s primary regulatory demand management tool is its alternate day watering ordinance. Begun in 2000, the ordinance spreads and shaves peak usage by allowing all customers to water up to three days per week depending on their address.

“The water waste ordinance and rain sensor ordinance also help us manage our irrigation demand,” says Cefalo. “These ordinances are supported by two field staff who leave notice of violation for customers out of compliance.”

Cary has had year-round watering ordinances since 2000. Restrictions were temporarily instituted in 2008 as a result of the drought.

Cary has required separate irrigation meters since 2002.

“We have irrigation design specifications and require customers to submit irrigation plans,” says Cefalo. “The two has recently installed an AMI [Advanced Metering Infrastructure] system and will soon launch a Web portal for customers to view their consumption–even as fine as on an hourly basis.”

With new construction, Cefalo says she observes an increasing use of warm season grasses and fewer automated irrigation systems being installed. Those doing retrofits are taking advantage of the free precision spray nozzles offered to those customers requesting an irrigation audit. The town also offers WaterWise workshops focusing on plant selection, landscape design, and rainwater harvesting.

The droughts of 2002 and 2007 to 2008 prompted several water efficiency measures in Cary. After the latter drought, the town instituted three new programs: the turf buy-back and high efficiency toilet rebate programs and a program on building a rain barrel sold at cost. All programs have remained since.

The energy-water nexus is becoming increasingly emphasized in some community programs.

In Valparaiso, IN, the city’s utilities department sends special statements with each month’s bill that usually focuses on water conservation, notes Jim Pingatore, water conservation planner.

“Our program is one of public awareness and public education,” he says.

A recent statement promoted the water-energy nexus by encouraging WaterSense showerheads, pointing out that showering accounts for nearly 17% of indoor residential water use or about 30 gallons per household per day.

“The last sentence of the message says that with less energy required to heat the shower water, you also save on electricity which equates to saving $70 a year on your utility bills,” says Pingatore.

Odd/even watering days is the most popular way to institute demand management programs, says Brian Vinchesi, president of Irrigation Consulting in Pepperell, MA, and the 2009 EPA WaterSense Irrigation Partner of the Year.

“The problem is when you tell somebody who’s used to watering every day that they can water every other day they more than double their time, so they actually use up more water,” says Vinchesi. “You’ve got people who go to one day or two days a week, and most people don’t know how to manage that.”

Photo: Global Water
Many utilities find that encouraging homeowners to replace lawn with droughtresistant landscaping helps significantly reduce residential demand.

Vinchesi says instead of a dictated water schedule, he’d rather see municipal require the use of smart controllers.

“The smart controller decides when the best time is to water,” he says. “Just because you can water every day or every other day a week doesn’t mean you have to if you have a smart controller.

“I have a mandatory every other day schedule where I live, but the state of Massachusetts is going to go to a mandatory one day a week,” he adds. “I don’t know a soil in the whole state that can hold one inch of water in a week. There’s no science. It’s all politics or knee-jerk reaction.”

Rebates can help in community efforts to reduce water use, Vinchesi says.

“Education is huge, and, as much as I hate to say this, licensing is needed,” he says. “Anybody can be an irrigation contractor. There are no barriers to entry. There’s very little education. There’s no incentive unless it’s required. I’m a big proponent of licensing of irrigation contractors because they know water and water is very important.”

New Jersey and North Carolina have been successful with licensing programs, adds Vinchesi. Vinchesi says the United States is getting better in establishing “green codes” which require more water efficient building construction. Unless a new building is being constructed under such codes, or as a WaterSense home or Leadership in Energy and Environmental Design (LEED) for homes, that is usually the only time a home is built to be water efficient, he says.

“Unfortunately, on the residential side, the cheaper you can put it in the better, but cheaper may not be more water efficient,” he says.

Retrofits are helping water efficiency, Vinchesi says.

“Most systems get better because they are being retrofitted with newer technology,” he says. “If you just change a sprinkler that was made in the 1980s to a sprinkler that was made in the 2000s, you’re going to get a better sprinkler. It’s more efficient and more uniform in putting its water down.”

For water agencies, demand management often comes in the form of undertaking education or rebate programs to help customers reduce water demand, especially in peak periods such as summer. To that end, technology often helps to achieve high efficiencies.

Using smart irrigation technology aids in demand management for water agencies.

“As water supplies dwindle, cities and agencies must secure more reliable water sources,” says Chris Spain, CEO and president of HydroPoint Data Systems, manufacturer of WeatherTRAK smart irrigation controllers. “Conserving water is the lowest cost source of water for providers and their customers, particularly when compared to developing new infrastructure or purchasing water from wholesaler agencies.”

Landscape irrigation often presents the greatest conservation opportunity for communities as anywhere from 30% to 60% of local water supply is used outdoors, Spain point out.

“The EPA and other experts estimate that as much as 50% of landscape water use is wasted due to overwatering caused by inefficiencies in irrigation methods and systems,” he says. “Agencies educate both commercial and residential customers about the benefits of smart irrigation with landscape and outdoor water audits as well as rebates.

“Adding a weather-based smart irrigation controller to an existing system is a cost-effective, simple upgrade that creates immediate efficiency and water bill savings. A smart irrigation controller that offers real-time, accurate evapotranspiration [ET] weather data, an automated scheduling engine, and either SWAT [Soil and Water Assessment Tool] accreditation or the EPA WaterSense label ensures superior product performance and reliable results.”

HydroPoint has worked with cities including Santa Clarita, CA; Houston, TX; and Charleston, SC, to address the rising costs of irrigating city parks, landscape districts, and facilities, as well as community concerns over runoff and environmental damage.

After Newport Beach, CA, offered a WeatherTRAK controller program to residents of the Buck Gully area in 2007, the city achieved a 20% reduction in runoff to protect ocean coastline in the area. HydroPoint’s Smart Yard program now offers homeowners in Riverside, Petaluma, and St. Helena, CA; and Salem City, UT, a turnkey installation of a WeatherTRAK controller that is financed by water utilities with a low-cost program fee on the customer’s monthly water bill.

Spain says people are starting to understand the role water has on energy.

“Virtually everything has water embedded somewhere in the supply chain and manufacturing process,” he says. “Landscapes typically contribute 20% of a property’s value and on average account for 58% of all urban water usage.”

Landscapes are routinely over-watered by 30 to 300%, presenting a high-value target for agencies’ demand management programs, says Spain.

“In addition to water, energy, and cost savings, any reduction in landscape over-watering also lowers the damaging environmental effects of runoff, which transports landscape chemicals and other contaminants into the local water supply,” he points out.

“Weather-based smart irrigation controllers apply the right amount of water at the right time, protecting communities from plant loss, slope erosion, hardscape damage, mold and mildew risk for buildings, and the mass loading of pollutants in water supply as a result of runoff,” adds Spain.

He also points out that EPA links water and energy savings, equating 1 gallon of water use with 4 watt-hours of power, creating a direct correlation between energy and water use.

“The California Energy Commission estimates that almost 20% of the state’s electrical response use and more than 30% of non-power plant natural gas use is related to the transportation and treatment of water and wastewater,” he says.

Spain points out that there is now legislation influencing the use of smart irrigation technologies by local water agencies and cities. Case in point: California Assembly Bill AB 1881 required local agencies, counties, and cities to implement water efficient landscape ordinances by 2010, spurring adoption of smart controller technology and requiring water budget allocations for large-scale landscapes.

Recent updates to California’s building code now require the installation of smart irrigation controllers on both residential and commercial new construction. California water agencies are also required by SBX7-7 and AB1420 to actively promote water conservation initiatives, with the goal of achieving 20% reductions in water use by 2020.

“We see similar legislation being discussed in Florida, Georgia, Texas, and other regions where water supply is pressured by increased demand, drought or changing weather patterns,” says Spain.

Toro’s Precision Series Spray Nozzles and Precision Series Rotating Nozzles are commonly used in the West and Southwest, usually promoted through rebate programs or educational efforts as part of a larger water efficiency management plan, says Mike Baron, the company’s National Specifications Manager for Water Management Products.

“The technology that has typically been used has had a high flow rate and high precipitation rate–anywhere from 1.6 inches per hour to two inches per hour,” notes Baron. “Using these higher efficiency nozzles, the flow rate is lowered, and uniformity is enhanced such that the amount of water being discharged in a given time by a sprinkler system is lower even to about 50%.”

A second area that’s taking hold is the encouragement of homeowners to replace sections of lawn with drought-tolerant plant material irrigated with drip products, says Baron.

“Another way to affect demand management is lowering flow rates significantly down to the gallons per hour rate and changing the plant material that’s being installed or upgraded in a landscape,” he points out. 
About the Author

Carol Brzozowski

Carol Brzozowski specializes in topics related to resource management and technology.

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