RGDSS_Historic_CUreport_20040601

Figure 2 Estimated Sprinkler Acreage and Total Acreage 1950 through 2002 sooooo 700000 600000 500000 N N 400000 L V a 300000 200000 100000 Total Acreage ~ ~ Sprinkler Acreage Generate the Ground Water Supply Acreage and Pumping Capacity Time Series Acreage with ground water supply and the corresponding well pumping volume are based on the well-matching routine developed for RGDSS and outlined in the memorandum Task 3.1 -Data Centered Ground Water Model, June 2002, developed by the RGDSS Spatial System Integration Contractor. The following steps were performed to generate the time series of acreage with ground water supply. 1. Acomma-separated file (we112002.csv) was provided by the Spatial System Integration Contractor that identified each well assigned to a parcel, the well permitted capacity, the well permit date, and the well appropriation date. 2. This file was input into the well processing program (wellproc.bas) used to create the annual time series data input file. For each year in the analysis (1950 through 2002), the acreage and pumping capacities of parcels under a structure were accumulated if either the well permit or appropriation date was active for that year. The amount of acreage with ground water supply and corresponding pumping capacity rose from 1950 through the mid 1970s, but has remained relatively constant since that time. Figure 3 shows the estimated irrigated acreage with ground water supply from 1950 through 2002. Also shown is the estimated total irrigated acreage for the time period. Figure 4 shows the estimated irrigated acreage with ground water supply (left axis) and the corresponding permitted pumping volume (right axis). C:\Projects\rgdss\finemos_2004\appendA_cropcu_6-2004.doc A-8 of A-10 June 2004 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000