A move by South San Joaquin Irrigation District to possibly become the first irrigation district in California to go to a 100 percent pressurized delivery system may pay unexpected dividends in reduced ongoing maintenance costs.
Less maintenance and operational expenses coupled with water savings could create a significant reduction in costs and increase revenue from out-of-district water sales. If that happens, less revenue would be needed from the SSJID’s Tri-Dam Project power sales to help with irrigation expenses, which in turn increases the cash available to pump into the proposed retail power service.
That would have significant implications for reducing retail power rates. Even without a surge in Tri-Dam Project revenue the district’s plan to reduce retail power costs 15 percent across the board has been declared as financially sound by an independent consultant specializing in power markets. The consultant was retained by the San Joaquin Local Agency Formation Commission that is still trying to decide the fate of the SSJID application after nearly five years.
The SSJID board earlier this month opted to suspend plans for now to perform distribution system related maintenance work until a $750,000 study is completed to see if the Division 9 pressurized delivery system success story can be replicated district wide. The study is expected to be completed next September.
“It doesn’t make sense to invest significant money into major upgrades if we won’t need them in a few years’ time,” noted SSJID General Manager Jeff Shields.
If a study shows it is possible, pressurization would revolutionize the district business and operational models making it the only known water district in the United States to mesh cutting edge tablet and smartphone technology with the latest drip irrigation advances.
Shields said based on what the study finds the district could opt to convert the rest of the SSJID to pressurized delivery at once or in phases. The main canals would still exist although other components of the system would be converted into pipeline.
The end result could include:
•Significant reduction in water use and losses as pressurized drip reduces evaporation seepage and also waste as water is applied directly where it is needed. The district’s abundance of orchards and vineyards makes drip irrigation feasible on a large scale. It also would eliminate spillage at the end of district canals into creeks and sloughs.
•A drastic reduction on pumping from underground aquifers which in turn could help combat salt water intrusion issues for nearby cities, farmers who aren’t accessing SSJID water, and private residences that rely on well water.
•Essentially expand the effectiveness of SSJID water supplies during dry periods by being able to irrigate more crops with less water.
•Reducing costs to growers by reducing water use and provide a pressurized system where fertilizer and other applications can be applied via a closed system. It also has the potential to cut electricity consumption.
•Reduce air pollution by eliminating diesel powered pumps used by farmers as well as the district.
•Making it possible for the SSJID to further reduce costs for field manpower needs that comes from the need to constantly repair and maintain open canals.
•Eliminate safety hazards posed by open canals.
•Increase district revenues via the sale of conserved water through out-of-district purveyors.
The proposed pressurization could have an impact on ground water recharge since it eliminates water spillage at the end of the SSJID system and could drastically reduce flood irrigation. Some 40 percent of the 250,000 acre feet of the water the SSJID imports from the Stanislaus River watershed ends up recharging aquifers The biggest source of groundwater recharge in the region is from the district’s Woodward Reservoir. That would not change.
Converting to a closed system also would mean how the cities of Escalon and Manteca use the district’s canal systems for storm run-off may have to change.
Shields noted the district employed a system similar to the ones that airlines use to allow travelers to book flights on line to allow farmers in District 9 to use tablets or smartphones to book water deliveries. He said that if the system is implemented, ditch tenders would be seated behind computers much of the time monitoring water flows and not having to drive along canals all hours of the day to open gates and lift irrigation boards.
Groundwater salinity concerns prompted the board to implement the Division 9 pressurized system
The Division 9 pressurized system south of Manteca and west of Ripon coupled with a three-year investment of $4.5 million to help farmers throughout the district implement more efficient farming practices has saved the district over $3.5 million so far. Both the growers’ conservation program and the Division 9 pressurized system also saved enough water to allow SSJID to net $4 million more in out-of-district water sales to other water purveyors.
Shields noted the cost of pressurizing of the entire district will not impact the SSJID efforts to use Tri-Dam receipts to reduce retail electrical rates by at least 15 percent in Manteca, Escalon, and Ripon.