The Economics Of Water Use: Irrigation

But it’s not likely to stay that way. Local governments strapped by short supply and the high demands of growing populations are making decisions that will restrict water use, raise rates and enforce penalites on the violators. Rather than a threat, however, professionals in the lawn and landscape industry should see it as an opportunity.

Helping residential and commercial customers get and stay in compliance with ordinances as they are implemented will be a major source of business for contractors as water supplies continue to be stretched and governments are forced to make tough policy decisions.

STATE OF THE UNION. The United States uses 19.4 billion gallons of fresh groundwater a day for public and private supply, irrigation, livestock, manufacturing and more, based on the National Ground Water Association’s research. Eighty-one percent of the public water supply is groundwater, according to The Water Encyclopedia. It also lists typical urban water use by a family of four for lawn watering and swimming pools at about 100 gallons per day, or 30 percent of the family’s daily total consumption.

Considering this level of demand, we should be seeing some significant changes in the cost of irrigation water, particularly in the Southwest. But even doubling the price to $.0018 probably is not going to have much of a bite, unless you consider a 23-acre business park that soaks up 75 million gallons of irrigation water a year. Then there is a more obvious opportunity for water (and monetary) restitution.

Because water’s price isn’t consistent with its value, the Safe Drinking Water Act and the Clean Water Act might ultimately have to garner industry and consumer reflection.

“During the next five years, we’ll see continual increases in the (water) rates that will become an inconvenience to the public,” predicted Donna Pacetti, water conservation specialist for Denver Water. “New regulations in the Safe Drinking Water Act and the Clean Water Act are going to affect the cost of water.”

WATER RATE VARIATIONS. The variability in the base cost of treated, municipal water available for residential and commercial irrigation across the country is vast - from $.68 per hundred cubic feet (748 gallons) in Albuquerque, to approximately $4 per CCF in Boston, Mass. Why this difference?

“We can only charge what it costs us to produce and deliver water,” explained Andy Terrey, water resource specialist for the City of Phoenix. Metro centers like Phoenix, Albuquerque, Las Vegas and Los Angeles are getting water consumers’ attention. Ordinances and programs offering incentives and “disincentives” for certain landscape and irrigation design and management practices are opening the eyes of both consumers and contractors.

“In selected water-short areas, the price of water is encouraging good conservation practices,” offered David Zoldoske, director of Cal State Fresno’s Center for Irrigation Technology. “Many municipalities are adopting two-tiered water pricing based on square footage of the landscaped area. Water is allotted based on historical evapotranspiration and plant material needs. Then, consumers are charged a higher rate for irrigation water used above that.”

MANAGING BEHAVIOR. Select water suppliers discourage “excessive” water use through tiered pricing. The cities of Tampa and St. Petersburg, Fla., have graded rates whereby higher use rates equate to higher charges. In St. Petersburg, commercial water rates are formulated by averaging an account’s previous 12-month use (a rolling average), explained Kathy Foley, water conservation analyst for the Southwest Florida Water Management District. The price per 1,000 gallons used within the average is $1.43; the average to 1.4 times the average is $1.79; 1.4 to 1.8 times the average is $2.43; and finally, more than 1.8 times the average is $2.86.

Las Vegas, a community known for its appreciation of water, imposes four tiers on its Las Vegas Valley Water District customers, noted Joe Fortier, conservation program coordinator for the Las Vegas Public Water District/Southern Nevada Water Authority. With a net gain of 5,000 people a month, odds are that water there will increase in value. “We recently developed a fourth tier (at $2.27 per 1,000 gallons) for the top 5 percent of water users within meter-size categories,” Fortier offered. “This top 5 percent is billed at a higher rate, strictly for water conservation.”

IMPOSED ALTRUISM. The benchmark in water conservation law was formulated, or at least influenced, by the landscape industry. After seven years of debilitating drought, many local California entities began adopting their own somewhat restrictive landscape and water use ordinances, said Marsha Prillwitz, environmental specialist for the Bureau of Reclamation, on loan from the state Department of Water Resources. “The landscape industry rallied and began to take political action,” she added.

California’s touchstone Water Conservation and Landscaping Act (AB 325) was passed by the state assembly in 1990. The Act required the Department of Water Resources to develop a state model ordinance for landscape water efficiency and conservation. The Model Water Efficient Landscape Ordinance was adopted in 1993, requiring 513 California cities and counties to adopt the state model or another ordinance, create their own ordinance or issue findings that no ordinance was necessary.

“Nearly half took a water budget approach, 174 imposed turf limits of 25 percent of the total landscape area, 60 issued findings that no ordinance is needed and 51 created a point system that rates landscape and irrigation designs on a point scale, with a minimum number of points required to pull a permit,” Prillwitz explained.

CYBER COPS. Water cops are popping up all over, but these enforcement officials are more likely to be behind a computer than in a truck. Florida state law reads that all automatic irrigation systems must have a rain switch, punishable by a $500 fine. In Phoenix, large turf areas of 10 acres or more receive an annual allotment of water based on plant material, size and ET. If customers exceed their allotment once, they receive a 200-percent surcharge on the groundwater portion of the water used. The surcharge can leap to 1,000 percent if the violation runs into a third year.

Phoenix rules also require the use of approved low water use plants on right-of-ways and the use of effluent water in turf facilities of five acres or more.

Albuquerque has an ambitious ordinance that appears to be saving significant amounts of water. “The major elements of the ordinance are plant and irrigation design restrictions for new residential commercial landscapes,” noted Irrigation Conservation Manager Doug Bennett. “We limit the quantity and use of high water-use plants in landscape designs.

“We also offer a rebate program that provides $.15 per square foot of landscape that converts high water-use plants to xeriscape plants, with a cap of $250 per customer,” he added. “But the real incentive is generated through the water waste enforcement program.”

In 1995, the city took action against 286 violators. Bennett compared their annual water use in 1994, 1995 and 1996. “On average, they each conserved about 376,000 gallons of water in 1996. To date, we have enforced nearly 1,000 properties.”

EDUCATING USERS. Denver Water runs public service announcements about irrigation and water use on television during the summer months, Pacetti said. It also offers xeriscaping classes and a mobile auditing team that will come to a site, evaluate irrigation system performance and make recommendations to improve efficiency.

Plant guides and evaluation services are sprouting all over the sun belt. “Our goal is to educate landscape professionals and the public on how to conserve water before we ever have to take enforcement action,” said Fortier.

“We process a lot of requests for water use information from all sectors of Florida,” added Foley. “People are becoming more proactive.”

INDUSTRY OPENINGS. What does this mean to the landscape professional? It means while you develop and hone your irrigation design and management skills, the public and private sectors will seek you out. Professional educational programs are available year round in all parts of the country. From the Irrigation Association’s design and auditing certification curricula to CIT’s sprinkler modeling software packages, you can develop conservation skills that the consumers are expecting and even demanding.

How much opportunity is there? Zold-oske claims that, based on field auditing and system modeling with software, the average residential and commercial system is less than 50 percent efficient. That means less than half of the water applied to landscapes is actually being used by the plant material.

What’s a realistic goal for irrigation efficiency? Irrigation consultant Steve Smith, president of Aqua Engineering in Fort Collins, Colo., said 80 percent efficiency is achievable.

“We set the threshold for significant monetary savings with new irrigation equipment and redesign at $100,000,” Smith said. “If a site has 100 acres or an annual irrigation water budget greater than $100,000, it needs a sophisticated control and management system. Chances are the proprietors can afford it. With that big of a cost, there’s a good opportunity for a capital investment to pay for itself in a few years.”

This should be easy to sell for large sites. Quantify annual irrigation water use based on previous billing statements ($100,000); run several catch can tests and determine system efficiency (say 50 percent efficient); project an improved efficiency based on system repairs and upgrades for improved performance and historic water needs (hopefully about 75 percent); translate that into dollar savings ($25,000 saved annually).

For smaller sites, be creative. Offer to pay the customer’s water bill for a year, based on statements from the previous year. Anything you save them, you pocket. Make minor system adjustments, like using the same make and model of heads for each zone, ensuring that sprinkler nozzling is uniform, moving or adding heads to improve coverage, operating the system at the prescribed pressures, installing a rain override switch on the controller and maintaining the plant material to prevent interference with sprinkler trajectories.

Add in regular scheduling adjustments that fit the site’s seasonally fluctuating microclimate(s), soil and plant maturity conditions.

Design for uniformity, management and the end user. Provide the plant only the water it needs at a rate that the soil can absorb. Keep the water in the active rootzone. Adjust runtimes as often as possible (at least monthly), and maintain the system with regular irrigation checks, actually watching the system operate during the day.