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OOlG58 Agricultural Notes California Farmers Adopt Tradable Loads Program to Reduce Selenium in Agriculture Irrigation Runoff Traditionally, water pollution trading policies have been designed for trades among point sources (such as factories) or between point and nonpoint sources. However, farmers in California have recently adopted a system of tradable loads to reduce the amount of selenium in runoff from irrigated fields as one part of an effort to deliver high-quality water to wetland habitats. This is possibly the first time a tradable loads program has been established among nonpoint sources. The Grassland Drainage Area, located on the western side of the San Joaquin Valley, is agricultural land that is farmed for cotton, cantaloupe, alfalfa, tomatoes, sugar beets, garlic, onions, asparagus, wheat, barley, and rice. Because much of the land in the Grasslands Drainage Area has a shallow layer of clay, it must be tiled to avoid raising the water level and damaging the crops. In other words, the land has been plumbed so that agricultural drainage water is collected in tiles under the fields and then pumped out through sumps. Unfortunately, the soil contains a high level of selenium, a naturally occurring toxic trace element. This selenium is carried out through the sumps by the agricultural drainage, threatening the health of birds and other wildlife that depend on the San Joaquin River. The San Louis Drain The San Louis Drain was constructed in the 1970s to carry the drainage water from several drainage areas, including the Grassland Drainage Area. It was originally intended to span all the way to the Sacramento-San Joaquin River Delta and serve several hundred thousand acres in the west side of the San Joaquin Valley. However, it was completed only part way and terminated at Kesterson Reservoir. In the early 1980s, selenium was detected in the water coming into the Kesterson Reservoir from another drainage area, and so the San Louis drain was closed and never used again - that is, until the farmers themselves got involved. Use Agreement with the Bureau of Reclamation Several irrigation and drainage districts (including all of the areas within the Grasslands Drainage Area), which are local government bodies, joined forces in March 1996 to exercise common powers for the purpose of managing agricultural drainage. The group is called the Grassland Area Farmers. One of the initial goals of the Grassland Area Farmers was to use the San Luis Drain for its original intent - as an outlet for agricultural drainage. To that end, they entered into a five-year use agreement on November 3, 1995, with the Bureau of Reclamation, the drain's owner. The agreement did not formally begin, however, until discharges commenced on October 1, 1996. The five-year term ends on September 30,2001. As part of the use agreement, the Bureau set a cap on the total amount of selenium that the Grassland Area Farmers could discharge. The cap was set to decrease for each of the last three years of the project, meaning less and less selenium discharge would be allowed over the life of the agreement. Plans are under way to complete another use agreement that would extend use of the drain for another five years. Tradable Loads Program The Grassland Basin Drainage Steering Committee (GBDSC), the governing body of the Grassland Area Farmers, first adopted a rule establishing a tradable loads program on June 26, 1998. Under the program, the total allowable regional selenium load is allocated among the member irrigation and drainage districts. The districts can either meet their load allocation or buy selenium load allocation from other districts. The theory is that the region as a whole will meet its regional load target at a lower cost than the cost without the trading. This is because selenium reduction measures will be taken where they are cheapest to implement. In addition, the program should spur innovation by bringing decision-making regarding selenium reduction measures to a more local level. Finally, the tradable loads program aims to distribute equitably among the districts the costs of selenium discharge reduction. 16 NONPOINT SOURCE NEWS-NOTES MARCH 2000, ISSUE 160