News Briefs - Spring 2018
Record Year Predicted on Salt-Verde System
According to the Arizona Department of Water Resources, 2018 is a record year, but this is not a record to cheer for. The water runoff season (January-May) in the Salt-Verde watersheds is likely to be the driest since records have been collected. ADWR’s Arizona Water News summarized the situation with information from multiple sources. The Salt River Project’s runoff totals in the Salt and Verde reservoir systems for the period January-March are at their lowest since 1913. These discouraging totals come in the wake of a disappointing December-February snowpack season, which produced most of the snowpack only at the highest elevations in the watershed. Using SNOTEL data, the Natural Resource Conservation Service estimated snowpack values in the range of zero to 40 percent of normal. The spring does not hold much hope for moisture either. Forecasts indicate Arizona will experience drier than normal weather through at least the first half of April, and chances do not look good for a “Miracle May” like the one that rescued the Colorado River in 2015.
Study Boosts Credibility of Cloud Seeding
In January, a study funded by the National Science Foundation proved for the first time that silver iodide introduced into clouds forms ice crystals that fall out as precipitation. Researchers in Idaho used radar and aircraft-mounted cloud physics probes to detect evidence of the processes that lead to precipitation. The results of the study, published in PNAS, indicate that cloud seeding can enhance natural precipitation. Although the study focused only on the physical chain of events—initiation, growth, and fallout of ice crystals—rather than the effectiveness of cloud seeding, it is being cited to justify further investments. A 2014 study conducted in Wyoming found that cloud seeding could increase snowfall by 5 to 15 percent. While a 10 percent increase would be a boon to water users, it is within the natural variation of winter storms and therefore difficult to attribute to cloud seeding. Despite these reservations, Arizona, California, and Nevada have funded cloud seeding in the Rocky Mountains for over ten years and they will share the cost of nine more years with Colorado, New Mexico, Utah and Wyoming. The PNAS article is available at http://www.pnas.org/content/early/2018/01/12/1716995115.
Phoenix and SRP Agree on Water Recovery
The City of Phoenix has entered into a 40-year partnership with Salt River Project to help ensure reliable water deliveries in the future during extreme drought and shortage conditions on the Colorado River. Under this first-of-its-kind agreement, SRP will reserve capacity in its extensive system of wells so that in the future Phoenix can recover long-term storage credits for water that was stored within the Salt River Project water service area. During the term of the agreement, SRP will provide Phoenix up to 20,000 acre-feet of water per year pumped from SRP’s wells located within the Salt River Reservoir District. The city will pay a one-time fee, then a fixed rate up to 100,000 acre-feet and a higher fixed rate past that threshold. For more information: https://www.srpnet.com/newsroom/releases/030818.aspx
Mission Garden Celebrates Agricultural Tradition
The Santa Cruz River was the source of irrigation water for thousands of years. Tucson has revived cultivation of traditional gardens near the Santa Cruz through its Mission Garden project. The garden is located on the historic floodplain at the site of a Native American village that was there when Father Kino first arrived in the Tucson area. Today the garden uses drip irrigation with potable water from Tucson Water, but they are prepared with a purple pipe system to take reclaimed water in the future. The site of community events and tours, the Mission Garden is hosting the 3rd annual San Ysidro Festival on May 19th. The festival celebrates the harvest of White Sonora Wheat, the first wheat variety introduced to North America. It is a revival of an old Tucson tradition that dates back to the early days of Spanish settlement in the region, blending indigenous and Old World food traditions. Learn more about the festival at: https://www.tucsonsbirthplace.org/
New Filtration Material Created
The Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia recently announced a breakthrough in water purification technology. The technology uses a newly designed form of graphene, a single layer of tightly packed carbon atoms forming a hexagonal lattice. A strong and flexible material, graphene has many industrial uses, including water filtration. The CSIRO design, called ‘Graphair,’ is made from soybean oil and is simpler, cheaper and faster to make than graphene. When tested on water samples from Sydney harbor, the Graphair membrane filtered out 99 percent of contaminants after only one pass through. The researchers hope it can replace the multi-stage processes currently needed. Learn more at: https://www.csiro.au/en/News/News-releases/2018/Tiny-membrane-makes-Sydn...
Hurricane Alerts Will Now Include Storm Surges
According to NOAA’s National Hurricane Center, 90 percent of hurricane-related deaths are caused by water—flooding, storm surges, and high surf. To reduce this number, the Center made changes to its warning system and began issuing watches and warnings specifically for storm surges associated with tropical storms and hurricanes. A storm surge warning is issued within 36 hours of “life-threatening inundation from rising water moving inland from the shoreline,” while a storm surge watch is generally issued within 48 hours. Storm surge maps are made available with watches and warning. For more information, see https://www.nhc.noaa.gov/surge/warning/.