San Diego County Water Authority secures transfer agreement with Imperial Irrigation District

By on December 11, 2017
San Diego County Water Authority

A historic water conservation-and-transfer agreement between San Diego County Water Authority (SDCWA) and the Imperial Irrigation District (IID) has been realigned for an additional decade in order to ensure deliveries of needed water for an additional decade. The SDCWA board of directors voted unanimously to extend an Exchange Agreement with the Metropolitan Water District (MWD) of Southern California by 10 years, requiring MWD to continue transporting conserved IID water to San Diego County through 2047.

The action by SDCWA’s board was necessary because of mismatched terms in the Transfer Agreement with Imperial Irrigation District and the related Exchange Agreement with MWD. While the initial term of the Transfer Agreement with IID was 45 years (2003-2047), the Exchange Agreement with MWD had an initial term of 35 years (2003-2037). Through the end of 2017, the Water Authority had the unilateral discretion to extend the Exchange Agreement by 10 years so that it aligns with the Transfer Agreement, or to end the transfer 10 years early, so that it aligns with the Exchange Agreement.

By extending the Exchange Agreement with MWD, the Water Authority gains two million acre-feet of conserved Colorado River water for delivery to the San Diego region between 2037 and 2047. The San Diego region could face significant supply shortages during future dry years without this water. Currently, about 20 percent of the San Diego region’s water is from the Water Authority’s conservation-and-transfer agreement with IID, and the volumes will continue to grow until 2021.

“Our independent Colorado River water supplies are a key component of the ongoing effort to develop our diversified and more reliable water supply portfolio,” said Mark Muir, chair of the Water Authority’s Board. “Using that conserved water helps fuel our economy and maintain our quality of life – and it has proven particularly valuable during droughts when less reliable supplies from MWD have been reduced.”

Transferred IID water is highly reliable due to IID’s senior water rights on the Colorado River. The Water Authority’s analysis shows that the price they pay for conserved IID water is competitive with what they pay for each acre-foot of MWD untreated water.

The Water Authority’s Exchange Agreement with MWD governs deliveries of conserved Colorado River water to the San Diego region. MWD owns the only conveyance that can deliver the water to the SDCWA – via the 242-mile-long Colorado River Aqueduct.

Increasing volumes of Imperial Valley water conserved have been delivered each year to San Diego County under the Transfer Agreement between the SDCWA and IID. That agreement is rooted in the historic 2003 Colorado River Quantification Settlement Agreement, which helped reduce California’s use of the river to its basic annual apportionment of 4.4 million acre-feet largely through water conservation-and-transfer agreements.