Challenges and opportunities: How Washington dairies are working to keep our water clean

Water is a critical element in the success of any dairy farm.  As described in What’s All That Water For?, dairies of all sizes use water for a variety of purposes: “Providing fresh drinking water for the herd, keeping the crops hydrated when Mother Nature doesn’t provide enough rain, and re-using stored waste water to clean and flush the barns are all typical water uses on a Washington dairy farm…. Every drop of water on a typical Washington dairy farm is used an average of eight times!” Because Washington’s dairy farms use water for their crops and livestock, they accept a special responsibility to protect water resources. Dairy farmers utilize extensive planning, best management practices and emerging technologies to both minimize their use of water and ensure that surface and ground waters are protected from pollution. CAFOs and water management, past and present There are 13 licensed, certified, large “concentrated animal feeding operations” (CAFOs) in Washington.  The term “large CAFO” refers to a farm that has at least 700 cows and 1,000 heifers (a heifer is a young cow that is not yet producing milk).  Most farms fall under “medium CAFO status,” which means 200 cows and 300 heifers. In Washington, all large CAFOs are required to obtain a federal Clean Water Act permitto operate.  Medium CAFOs can be covered under a general permit, also issued by the state.  In order to obtain coverage under a general permit, farmers must apply to the state’s Department of Ecology (DOE).  Both permits prohibit all waste discharges into the state’s waterways.  The only allowable exception to this rule comes into play in the event of a “25-year, 24-hour storm event” (a rainfall so severe that it is only likely to occur once every 25 years). The Washington State general permit requires each dairy to “have a current animal waste management plan.”  This requirement was established in the 1998 Dairy Nutrient Management Act, a law enacted by the Washington State legislature with dairy industry support.  The Act made significant changes in waste handling procedures by the industry and has been credited with major improvements in the cleanliness of the state’s waterways. Lower Yakima Valley challenges In certain parts of Washington, environmental conditions and the prominence of varied industries creates special challenges in protecting surface and ground waters.  The Lower Yakima Valley of central Washington is home to a variety of agricultural enterprises including dairy – in fact, Yakima County is the 12th largest dairy-producing county in the U.S.  The Valley’s unique soil, topography, climate and water availability provided for a very long and diverse history of agricultural production, which is now a focus of special concern.  Nitrate contamination of ground waters – most likely originating in multiple sources, including historic farming practices – and suspended sediments in surface waters have emerged as major challenges requiring solutions. Since 1994, the Yakima Conservation Districts (North and South), Roza and Sunnyside Irrigation Districts and the Washington State DOE, along with many other groups, have been working with farmers of all types to reduce sediments and contamination in the Yakima River Basin, including the Moxee Drain, Granger Drain and Sulphur Creek Drain. The primary problem has been identified as furrow irrigation, as this method of irrigation is known for causing sediment flow from farm fields. While efforts to reduce the impact of agricultural uses on Valley waterways also began around 1994 (with some beginning even earlier), dairy CAFOS found themselves blamed for much, if not all, of the problem, likely due to their prominence in the region.  An activist group calling itself the Community Association for Restoration of the Environment (CARE), based in Outlook, Washington; and the Western Environmental Law Center of Eugene, Oregon, even threatened to sue ten dairies for violations of the Clean Water Act. Only one was actively pursued in court, and was ultimately was made to pay a $600,000 settlement. Those settlement monies were used to fund three water studies in the Lower Yakima Valley, including one by the state’s DOE. The Granger Drain and its watershed were especially identified as areas with significant levels of contamination.  It is important to note that no one source can be singled out as “the” sole polluter, since the state’s DOE only utilizes samples collected downstream of the Yakima River and its basins.  In fact, it is likely that a good deal of the pollution is decades-old, resulting from older farming practices no longer employed.  Non-agricultural sources also contribute to the problem. Dramatic improvements Recent studies confirm that dairy farmers and other CAFOs have been doing their part to protect Yakima Valley water resources.  In March 2009, the Roza-Sunnyside Board of Joint Control issued two reportsthat document major water quality improvements in irrigation waterways within the Roza and Sunnyside Valley Irrigation Districts during 1997-2008. One says that for the four waterways it monitored (including the Granger Drain and Sulphur Creek Drain), “suspended solids, phosphorus, bacteria and organic nitrogen+ammonia…. decreased by 42 to 90% between 1997 and 2008.” Each dairy farm can use individual strategies for treating and cleaning their wastewater. A lagoon is common practice, but other technologies include:

  • Tailwater return systems.
  • Improved water use efficiency to reduce wastewater storage needs.
  • Concrete slabs for storage of solid manure or feeds.
  • Backflow prevention, including air gaps and mechanical devices.
  • Solid/liquid manure separators with settling basins and mechanical separators.
  • Groundwater monitoring wells.
  • Irrigation monitoring equipment. 
  • Infrastructure like pumps, pipelines, mixing chambers and flow meters.
  • Pumps and pipelines to collect and convey runoff.
  • New Irrigation Application Technologies.

We began this post by observing that access to clean water is essential for the survival and success of every dairy farm.  It has become clear that the water quality challenges facing the Yakima Valley and the state as a whole are rooted in many sources.  Washington’s dairy industry has demonstrated a willingness to accept its share in creating the challenges that confront us.  But more importantly, it has demonstrated that it is ready to change its production methods in the light of new information and with the help of new technologies, making significant contributions to addressing our water quality problems.  Evaluating all sources of surface and groundwater pollution in the Yakima Valley and beyond, as well as cooperation from all industries and communities, will be crucial to continued improvements in water quality. 

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