For years, water policy analysts and hydrologists have questioned the benefits of agricultural water conservation in a conjunctive use system. This project investigated the most important aspect of the debate: whether or not adoption of precision technology like drip and microsprinkler irrigation has yield benefits. If it is true that precision technology increases the amount of farm output produced with a given amount of water, then surplus water can be reallocated from agriculture without appreciable impacts to farmers or rural communities (i.e. employment effects). As a 5 or 10% reallocation from agriculture to the environment would solve many instream quality problems, this line of research is significant even if the yield benefits are small.
Working with field-level data in Westlands Water District, NHI and project partners are statistically estimating the relationship between technology choice and yield per acre. Preliminary estimates indicate that, controlling for environmental conditions, processing tomato yields are 10-15% higher when drip irrigation is used than when furrow or sprinkler irrigation is used
