A new approach to water conservation

An instrumentation expert with the State Climate Office at North Carolina State University works at one of the automated weather stations at a higher-elevation site in the state.

The driest weather on record has prompted researchers to review better ways to efficiently manage water usage. The department of crop science and the state climate office at North Carolina State University (NCSU) in Raleigh, N.C., have collaborated on taking a new approach to conserving water and protecting the environment. They developed the Turf Irrigation Management System (TIMS), a free, Internet-based resource to irrigate more efficiently.

“Our approach to improving water-use efficiency is to give the irrigation user a way to better determine what the irrigation requirement is, and then to reinforce the necessity of actually measuring how much they are applying,” says Charles Peacock, professor of turfgrass science in NCSU’s crop science department. “This moves irrigation management into a more quantitative approach rather than a guess.”

How it works

“Although the system is live and has been used, it is still under development to further refine the end-user elements and make the climatic data more specific to the user location,” Peacock says.

The system works through the state climate office of North Carolina’s Climate Retrieval and Observations Network of the Southeast (CRONOS) database of automated weather stations. “CRONOS is a comprehensive database that archives and disseminates historical and real-time observations from several different networks,” says Ryan Boyles, state climatologist and director of the state climate office. “Each network has unique measurement formats and standards, and CRONOS tries to bring all high-quality observations into a one-stop shop.”

The weather stations are located at various sites throughout North Carolina. Currently, the state climate office has 101 automated stations in the state that provide key measurements necessary for the TIMS system, Boyles says. More than 105 other weather stations are available, he says, “but they do not report in real time or do not measure the needed variable for TIMS.”

The majority of the automated stations are near urban areas. Their location depends on the network purpose and need, Boyles says, but most of the stations are located at airports (more than 60) and agricultural research stations (30).

These specific automated sites record information necessary to calculate evapotranspiration rates, Peacock says, and they also record rainfall.

The TIMS Web site, www2.turffiles.ncsu.edu/tims , guides users through a step-by-step process that will help them determine how to improve irrigation practices and conserve water.

“The program’s algorithms are set to calculate an irrigation requirement based on questions asked when someone registers to become a user,” Peacock says.

Questions asked include: What kind of turf and types of soils do residential and commercial clients have? What irrigation system do they currently use? The more accurate users answer the questions, the better. “The most important information that users need to supply is their irrigation system application rate,” says Dan Bowman, a NCSU irrigation technical specialist. “This is determined by the ‘canning’ procedure described in step four. This takes some effort on the part of the homeowner, but it is critical if they hope to benefit from TIMS. The program is only as good as the data entered.”

Bowman, who helped provide guidance to the TIMS project regarding some of the technical issues involving soils, rooting patterns and turfgrass water needs, believes TIMS will save water if fee schedules for water use are affordable. “If a community has a flat-fee structure, you can save or waste water without much impact on cost,” he says. “People usually respond to incentives, especially monetary incentives, so the fee structure can be a very important component of water conservation.”

He predicts TIMS users will save at least 25 percent in water costs, “but, of course, since much of North Carolina is under some level of water restrictions, TIMS may not be useful until we fill up the reservoirs and are allowed to irrigate again.”

While using the TIMS online system, users are prompted to place containers throughout the irrigation area to measure the amount of water they are using over timed intervals. Once users enter this data and their account is established, TIMS calculates the amount of irrigation the user needs and keeps track of when, and how much, water is actually used.

“Once a user registers, the system records the location’s address, and when the user inquires about the irrigation demand, the program queries the closest North Carolina CRONOS weather station to that location for the climatic and rainfall data,” Peacock says.

Ultimately, TIMS calculates the irrigation needed by the user’s turf, based on recent weather conditions, including precipitation and evaporation.

Automated weather stations are located throughout North Carolina and neighboring states. The green dots designate North Carolina State University stations. The red dots designate National Weather Service stations. The dark red dots designate the department of transportation stations.

In the future, Peacock will strive to make the Web site easier to use, especially in showing people how to calibrate their irrigation systems with the use of video. He says representatives at the state climate office are working on using gauge-calibrated radar information to estimate rainfall data over much more localized areas.

“The next phase of our project is to use radar-based precipitation estimates, which will provide more accurate local rainfall instead of relying on reports from the nearest gauge,” Boyles says. “Rainfall, especially summer rains, can be very localized.” He adds that other measurements required by the TIMS system will come from the nearest weather monitoring station, but variables such as temperature, humidity and winds are not as locally variable as rainfall.

Peacock hopes this system will be used more during normal rainfall years versus in times of drought such that experience in 2007, which was the worst drought in the modern record for North Carolina, Boyles says.

In the state, rainfall varied greatly in 2007, but Boyles says in general, “the state had experienced less than 50 percent of normal precipitation since May. To completely eliminate the deficits, we need 30 to 50 inches over the next six months. Fifty inches over six months would be a record-setting wet period.”

Benefits

The extremely dry weather across much of the nation scares people, and it should. Water has become a precious commodity that many of us have taken for granted. “Everyone needs to practice water conservation both from an environmental stewardship, as well as an economic, perspective,” Peacock says. “Anything that a turf professional does to promote sound environmental stewardship will also promote their business and industry. We believe that this system will help people across North Carolina to practice better water conservation for their lawns, landscapes or other turfgrass areas in this critical time for water resources.”

Over time, turf professionals, homeowners and commercial clients will benefit from TIMS. Boyles says TIMS is designed to specifically allow users to minimize irrigation time and amounts while still maintaining the needed water to prevent damage.

“While it saves water, which is becoming increasingly expensive during drought, it also provides guidance during normal or wet periods that can prevent the development of diseases due to over-irrigation,” Boyles says.

The awareness that a water shortage problem exists is a good first step in turf professionals and their clients taking action. Many have recognized this concern, especially in drought-stricken areas, where people are proposing to develop stronger incentives for reducing water use, Peacock says. The ideas center around a tiered rate structure for water. He says the use of a decision aide such as TIMS will help in taking the guesswork out of determining how much irrigation is required to keep the turf healthy.

The author is a freelance writer in Danville, Va., and can be contacted by e-mail at rockyagwriter@aol.com .