COST-CONSCIOUS CONSTRUCTION FOR CALCULATED WATER DISTRIBUTION
California's South San Joaquin Irrigation District's two-component irrigation system has virtually eliminated water waste at 52 customer connections spread out over 3,800 acres. Farmers who chose to participate in the pilot project now customize and manage water deliveries online instead of manually phoning in orders and being restricted to scheduled delivery times.
The district and Stantec Consulting spent three years and $14 million upgrading infrastructure and developing software similar to ordering airline tickets online. During construction, neighboring water districts who'd heard about the project began calling and requesting tours. The effort eventually attracted the attention of the U.S. Department of Agriculture, which sent Deputy Secretary Kathleen Merrigan out for a site visit in 2011.
Delivering an innovative but cost-effective hardware/software integration required exploring alternatives to “traditional” design and construction methods. The following are just two examples of how this saved the district $8 million overall.
DATA TRANSFER. Water connections are designed to respond to individual requests from a centralized system and provide each farm with access to the pressurized pipelines. Communication with and between turnouts and meters would typically be provided by a fiber-optic network, a $4.5 million option that probably would've proven temperamental during construction and been difficult to effectively power.
Instead, solar-powered connections link to the pump station and supervisory control and data acquisition (SCADA) systems via secured wireless Ethernet. Each connection site has a programmable logic controller (PLC) that works with a local synchronized clock to open and close valves based on each farmer's scheduled delivery time.
SUPPLY AND STORAGE. Instead of placing a storage basin on two sides of the project area, hydraulic analysis determined that a single, seven-acre basin could amply support the network.