Owner: Glenn-Colusa Irrigation District
Location: Sacramento Valley, California
Funding Source: Glenn-Colusa Irrigation District
Completion Date: 2010
Glenn-Colusa Irrigation District (GCID) is the largest irrigation water supplier in the Sacramento Valley, typically diverting more than 800,000 acre-feet of water on a nearly year-round basis to serve 175,000 acres of irrigated crop land, wildlife refuges and managed wetlands. The dominant crop is rice. Since 1964, GCID has prepared an annual Water Measurement Report (Annual Report) that serves as a record of annual water diversions, operations, and uses. It consists primarily of a series of tables that summarize water diversions, deliveries, drain flows and drain water recapture on a monthly and annual basis, and contains a large amount of information and enables tracking of trends in certain operating parameters. The Annual Report also documents the water rates, rainfall, cropping patterns, and policies in effect each year.
Until 2009, GCID maintained a spreadsheet-based data management system that had been designed to produce operational reports and summary tables contained in the Annual Report. The spreadsheet system employed macro programs to enable semi-automated data entry, but the data was stored in a highly compartmentalized manner, making data access, analysis and reporting difficult. The system performed adequately for nearly 20 years for routine operations but was cumbersome for investigative analyses and ad hoc reporting, and it was not structured to receive and manage data from GCID’s expanding SCADA network.
In early 2009, GCID engaged Davids Engineering to migrate its spreadsheet data system to a Microsoft Access relational data base. This involved extracting data stored in hundreds of spreadsheets and assembling the data in one large Access data base. All of the historical data was salvaged. The new data base retained as much of the terminology as possible from the old system, including measurement site reference numbers and names. Like the old one, the new system includes data input screens designed to facilitate hand entry of operator reports submitted orally by radio and in writing. The GCID annual Water Measurement Report can now be prepared almost literally at the push of a button, compared to taking several weeks with the old spreadsheet system, and errors in compiling data for the report have been virtually eliminated.
One major objective of the conversion to a data base environment was to accommodate the growing volume of operational data that is expected to come from GCID’s ever-expanding SCADA system. Over time, it is expected that GCID’s reliance on SCADA information will increase and manual operator reporting will decrease. This trend is typical of many irrigation districts that are implementing SCADA systems for remote monitoring and control of water distribution systems.
It is anticipated that the capacity limits of Access will be eventually exceeded and the data base system will have to be migrated to a higher capacity platform, such as SQL server or Oracle. This migration will be relatively straightforward now that data is stored in data base tables. Eventually, GCID intends to house or access all of the data needed for water balance analysis in an integrated Water Information System (WIS). A major consideration in the design of the WIS is to enable routine updates of GCID’s water balance model, also developed by Davids Engineering.