Issue link: http://winesandvines.uberflip.com/i/74666
GRAPE GRO WING Overview of Cropland Input and Output Cropland Nitrogen Inputs Irrigation water 29 Atmospheric deposition 12 fertilizer 204 Land-applied biosolids 4.8 WWTP-FP 3.4 Land-applied liquids, Land-applied manure from CAFOs other than dairy 0.9 Land-applied dairy manure 127 Cropland Nitrogen Outputs The left half of the pie chart represents total nitrogen inputs (in giga- grams of nitrogen per year) to 1.27 million hectares in the study area of Tulare Lake Basin and Salinas Valley in 2005. The right half of the pie chart represents total nitrogen outputs with leaching to groundwater. Harvest 130 Synthetic Leaching to groundwater 195 Atmospheric losses 38 Runoff 18 Four areas of action Despite the fact that altering current farming practices related to nitrogen inputs will not show effects on groundwater quality for a long time, the government will take immediate action to address groundwater quality related to nitrates. The UC Davis report concludes that regulatory actions up to this point have been insufficient to control nitrate contamination of groundwater. It suggests action in four areas: 1) Assuring safe drinking water in affected areas; 2) Reducing sources of nitrate contamination; 3) Monitoring and assessment of groundwater and drinking water; and 4) Revenues to help fund solutions. Action in any of these four areas could affect California winegrape growers in the ways outlined below. Treatment of drinking water containing high nitrates in situations not protected by existing water treatment would be very expensive. Monitoring domestic drinking water supplies for nitrate contamination is also expensive. And finally, the cost of state or local monitoring of a grower's nitrogen-management practices would be significant. Several revenue-generating schemes to pay for these actions were suggested in the report. One is to add a mill assessment rate to nitrogen fertilizer sales, similar to the mill assessment on pesticide sales in California. Another is to add a substantial excise fee to nitrogen fertilizer sales. A third is to implement a comprehensive statewide water-use fee, part of which would fund some of the actions mentioned above. Any of these actions would increase the cost of farming for California winegrape growers. Farming costs for state winegrape growers also will be affected by new regulations passed by California's regional water quality control boards (RWQCB) to address groundwater quality issues. Up until now, these regulations have focused on surface water WINES & VINES AUGUST 2012 57 SOURCE: VIERS ET AL. 2012 PER UC DAVIS STUDY