Irrigation district modernization By Charles M. Burt, PhD, PE, CID, CAIS


In/out pumps with variable frequency drives and sophisticated logic to control flows in and out of a new 200 acre-foot regulating reservoir in San Luis Canal Company in central California


The term “irrigation district” or “agricultural water district” in the Western United States generally refers to some type of public agency organized similar to a county. By state water code, a district has rules to follow (i.e., voting, transparency, organization, etc.) and is allowed to perform specific functions (e.g., distribute irrigation water, generate power, provide drainage, etc.). Board members may be elected by all registered voters in the district or by votes proportional to acreage farmed or some other arrangement specified in the code. The Board members hire a professional staff to run the district.


Districts in the West range in size from about 500,000 irrigated acres (e.g., Imperial, Idaho) down to many the size of 10,000 – 20,000 acres. Smaller sizes are generally difficult to maintain as economically viable units, and small districts tend to consolidate.


With the exception of Canada, Australia and some Latin American countries, there are very few viable “water user organizations” with structures and func- tions that closely resemble those of U.S. irrigation districts. Typically, international water user associations are top-down organizations that are formed by the government to collect money from farmers and to provide maintenance of government-owned canals and pipe-


20 Ir Irrigation rigatgation TODAY AY | Janu ry January 201 nua y 2018 18


lines. The money is rarely seen again by farmers, and farmers are not especially enthusiastic about the arrangement. This aspect, plus the lack of good water laws, lack of enforcement of regulations, corruption, issues with right-of-ways and land ownership, and dozens of other challenges, add up to fairly dysfunctional organizations in many countries.


Today’s needs


In the Western United States, many districts were constructed over a hundred years ago when on-farm irrigation was very simple, when there were no environmental laws or agencies and when a large percentage of citizens had seen a cow sometime in their lives. The primary function of an irrigation district until about 1980 was simple: maintain facilities and distribute water to farmers. Furthermore, the attitude was more or less that the farmers needed to follow the district rules because the district was in charge. There was usually not a conscious service attitude by district employees. It was also acceptable to divert a whole river into a large canal, run the river through the irrigation project and then discharge any nonconsumptive uses back into the river channel at the downstream end of the project. Everyone understood that the water was not wasted — it didn’t disappear — but no one was thinking


about the environmental impacts of drying up stretches of river.


The almost explosive growth of environ- mental specialists in recent decades has resulted in the recognition of numerous problems — often with regulations that do not solve those problems and which have little or no consideration of local economics and technical abilities. For example, a district may be pressured to increase water-use efficiency. However, inefficiencies within an irrigation district are often the only source of groundwater for a district’s neighbors. During years of drought, farmers within the district may also depend on wells that recycle this groundwater. On the other hand, allow- ing deep percolation from fields runs the danger of polluting the groundwater with nitrates. All facets of the situation must be examined, because both the problems and the solutions are complex.


Today, irrigation districts must continually respond to external pressures related to losing some of their water rights (a huge issue in California), basin-wide challenges such as groundwater overdraft, environmental regulations related to their drainage outflows, urbanization, and so on. Districts must deliver a high percentage of their diverted surface water, measure all deliveries and outflows with a high degree of accuracy, prevent environmental damage and provide


INFRASTRUCTURE


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