MWD Rolls the Dice with Our Water Supplies During Drought

Estimated 2016 Water Supply/Demand Balances and Storage Scenarios
Credit: Metropolitan Water District of Southern California

One would think an agency caught in the grips of one of the worst droughts California has ever seen would handle and account for its water supply with extreme prudence.  And yet, in attempting to avoid mandatory conservation measures, the Metropolitan Water District has grossly overestimated its projected water supplies when performing a state-required “stress test” to model water conditions in 2017, 2018, and 2019. Indeed, by my account, Metropolitan Water District could be overestimating future supplies by as much as 465,000 acre-feet over the next three years—interestingly, this is approximately the same volume Metropolitan projects will remain in storage at the end of 2019 (i.e. Metropolitan could completely run out of stored water in the next three years). In 2017 alone, Metropolitan could be over-projecting supply availability by nearly 310,000 acre-feet—that’s 18% of its projected 2017 demand!

I discussed some of the flaws of the “stress test” framework in my last blog, but as the self-certification submissions have trickled in, they’ve revealed a deeper failing of the framework: it offers water suppliers an exemption from their own water management rules provided they can show demand won’t exceed supplies by the end of 2019. That is, a water supplier could chart a course of usage that would deplete every last drop of waterincluding emergency suppliesand still not be required to implement mandatory conservation.  This is neither an appropriate nor sustainable strategy. 

As I feared, water suppliers are using overly optimistic supply projections to avoid mandatory conservation, and the Metropolitan Water District is a prime offender.  As a wholesale water provider to 26 member agencies and ultimately 19 million people in Southern California, Metropolitan draws water from two main sources: the Sacramento and San Joaquin Rivers via the State Water Project and the Colorado River via the Colorado River Aqueduct.  Metropolitan also maintains significant storage facilities to carry over unused supplies of imported water from one year to the next.

My analysis of the projected supplies—and flaws—in Metropolitan’s “stress test” is detailed below.

Supply Description Potential Overestimate
Storage Supplies 200,000
PVID Land Management Program 124,500
Binational ICS 24,000
DWCV SWP Table A Transfer 116,460
Total 464,960

Storage Supplies

As of January 2016, Metropolitan’s storage portfolio contained approximately 1.537 million acre-feet—626,000 acre-feet of which is considered emergency storage. That leaves 911,000 acre-feet of water available for non-emergency uses.  

1. In Metropolitan’s May 10, 2016 report to the Board of Directors Water Stewardship and Planning Committee, the District projects that it will draw approximately 628,000 acre-feet from storage in 2016, but will also add back 376,000 acre-feet by the end of the year. As shown in the table below, the resulting “2016 End-of-Year Storage Balance”  for CY 2016 ranges from approximately 1.1 to 1.5 million acre-feet in the “Low Storage” to “High Storage” scenarios, with approximately 1.3 million acre-feet dry-year storage balance in the “Current Trend” scenario.

However, according to Metropolitan’s “stress test” report, the estimated starting storage balance in 2017 will be 2,117,000 acre-feet. That number simply doesn’t match what Metropolitan previously reported. Why? For purposes of the “stress test,” Metropolitan appears to be adding the “high-storage” scenario to the emergency storage capacity—an awfully optimistic projection. Most water suppliers take a conservative approach in preparing forecasting plans, but Metropolitan is generous with this particular “stress test” projection. 

 2. In the “stress test,” Metropolitan also intends to pull 1.6 million acre-feet from storage over the next three years, leaving only 465,768 acre-feet at the close of 2019.  Even with the overly optimistic storage recharge and supply projections from the Colorado River (see below), Metropolitan is allowing storage levels to drop 160,000 acre-feet below current emergency levels—reducing Metropolitan’s emergency storage supplies for nearly half of California by 25%.

Supplies from the Colorado River

The Colorado River is Metropolitan’s original source, and the District has legal entitlement to it under a permanent service contract with the Secretary of the Interior.   In addition, Metropolitan has invested in farm and irrigation district conservation programs, improved reservoir system operations, land management programs, and water transfers and exchanges through arrangements with agricultural water districts in southern California, San Diego County Water Authority, and entities in Arizona and Nevada that use Colorado River water, and the U.S. Department of the Interior, Bureau of Reclamation (USBR).

Considering the extreme drought conditions in the Colorado River Basin and the record low levels of Lake Mead, Metropolitan is once again projecting far higher supplies than is reasonable. (Ironically, while Metropolitan was preparing its “stress test” projections, it was also negotiating an eight percent reduction of its supply from the Colorado River because of the drought.)    

The most troubling examples of MWD’s overly optimistic supply projects are as follows:

Palo Verde Irrigation District Land Management Program

Metropolitan projects that it will receive 130,000 acre-feet of water each year from PVID in 2017, 2018 and 2019, even though MWD has only received 88,500 acre-feet per year on average over the past 10-years (it received 32,800 acre-feet, 43,000 acre-feet, and 85,000 acre-feet in 2013, 2014 and 2015 respectively). That’s, at a minimum, a 41,500 acre-feet annual increase in available water—the certainty of which is unexplained in the report.

Binational Intentionally Created Surplus (ICS)

Metropolitan projects that it will receive 24,000 acre-feet of water from the Binational Intentionally Created Surplus in 2018 (but not in 2017 or 2019), despite the fact that this source is not made available when there is a declared shortage on the Colorado River and, as noted above, the Colorado River is currently experiencing extreme drought conditions that warrant reduced allocations and contract renegotiations. To be safe, Metropolitan should assume that a shortage will be declared on the Colorado River for the next three years and not count on this source being available.

Desert Water Agency/Coachella Valley Water District (DWCV) State Water Project Table A Obligation

The Desert Water Agency and Coachella Valley Water District have a contract to receive water from the State Water Project, but do not have the infrastructure to get water from it directly. So instead, Metropolitan functions as a go-between, pulling Desert Water Agency’s and Coachella Valley Water District’s owed volume from the State Water Project for itself and delivering the equivalent volume to those agencies from MWD’s Colorado River supplies via the Colorado River Aqueduct.  However, as shown in the “stress test,” Metropolitan is planning to keep DWCV’s SWP Table A allocation, which totals 116,460 acre-feet for 2017-2019, but not deliver that volume via the Colorado River Aqueduct.  Metropolitan refers to this arrangement as a “callback” which is not described in the 2015 Urban Water Management Plan referenced in the “stress test.”

Southern Nevada Water Authority (SNWA) Agreement Payback

Metropolitan Water District, Southern Nevada Water Authority, the United States, and the Colorado River Commission of Nevada entered into a storage and interstate release agreement in October 2004. Under the agreement, additional Colorado River water is made available to Metropolitan when there is space available in the aqueduct to receive the water.

Southern Nevada stored approximately 330,000 acre-feet with Metropolitan through 2015.  Returns to Southern Nevada are restricted to 30,000 acre-feet annually unless Metropolitan agrees to a larger amount.  Although Southern Nevada has agreed to not request return of the water stored prior to 2015 until 2019 (unless Metropolitan agrees to the return), there is no language in the agreement precluding Southern Nevada from requesting return of the 125,000 acre-feet stored during 2015.

In addition, in 2020 and 2021 Southern Nevada may request the return of 50,000 acre-feet or the difference between 280,000 acre-feet (Southern Nevada’s total basic apportionment) and what SNWA actually receives, whichever is less. That means that Metropolitan may be obligated to pay back significant volumes of water to Southern Nevada during a year when Metropolitan’s starting storage balance is 160,000 acre-feet below emergency storage levels.  Although under the “stress test” guidelines, Metropolitan is not required to consider what happens after December 31, 2019, ignoring this possibility contradicts Metropolitan’s claim that it will carefully manage reserves to avoid exhausting vital buffer supplies.

But it gets worse. The contract between Southern Nevada and Metropolitan also states that if less than 75,000 acre-feet has been returned, then for each year prior to 2027 that Lake Mead begins at or below 1,045 feet, Metropolitan will contribute 50,000 acre-feet of Intentionally Created Surplus (ICS) to Lake Mead, until the combined sum of Intentionally Created Surplus and water returned to Southern Nevada equals 75,000 acre-feet. For years that Lake Mead begins at or above 1,080 feet, Metropolitan can request delivery of ICS.  Lake Mead is currently at approximately 1,072 feet and is draining a rate faster than anyone projected.

While I didn’t include this as a potential overestimate of supply during the period of the “stress test”, it’s important to note that the payback to SNWA could result in substantial reductions in Metropolitan’s available supplies from the Colorado River.

Supplies from the State Water Project

Metropolitan appears to have followed the State Board’s self-certification guidelines for projecting State Water Project allocations in 2017, 2018, and 2019; Metropolitan used the same allocation percentage and volume as it received in 2013, 2014, and 2015 (35%, 5%, and 20%, respectively).  The concern with the State Water Project projections is that Metropolitan likely received additional water supplies as a result of water quality waivers and urgency orders on the State Water Project system. The self-certification guidelines specifically require water suppliers to assume those urgency orders will not be permitted in the next three years. Unfortunately, I was not able quantify exactly how much additional water resulted from those orders.

In Conclusion

As my colleague, Doug Obegi, pointed out in his blog last week, the State Water Board frequently fails to hold water suppliers accountable for their actions and inactions. Although the water board staff may not have the capacity to conduct extensive examinations of the over 400 “stress tests” that were submitted in June, I hope they will still hold water suppliers accountable for reckless and irresponsible responses to the state’s emergency drought regulations.

California wildfire

Notwithstanding some modest precipitation last winter, California’s drought remains severe, and our water planning warrants careful scrutiny. Meanwhile, we must remember that drought is not the only emergency that can impact our water supplies. As stewards of our water supply, agencies like Metropolitan need to maintain adequate storage and redundancy to ensure reliability should supplies be compromised by drought and additional emergencies. Years of drought and record hot years has resulted in a very active wildfire season in 2016; with continued drought, is it really unimaginable that key water infrastructure could be exposed to fire damage? It is also a possibility that an earthquake could compromise water infrastructure. By dipping into emergency storage supplies or overestimating water imports in order to evade mandatory conservation, Metropolitan is putting us all at risk.

Now is not the time to gamble with California’s water supply. In a letter sent this week, the State Board should reject Metropolitan’s self-certification report as well as the self-certification reports of any of its 26 member agencies that relied on the supply projections in Metropolitan’s report.

Research and analysis by Tracy Quinn, NRDC and Caryn Mandelbaum, Environment Now

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