Category Archives: Bay-Delta

How do we increase salmon runs in 2018 and beyond?

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Over the past few months, I wrote posts on the status of specific runs of salmon in rivers throughout the Central Valley. In this post, I describe the overall status of salmon runs and the general actions to take to increase both escapement and fish available for commercial and sport harvest.

It was just over a decade ago that there were nearly one million adult salmon ascending the rivers of the Central Valley (Figure 1). At the same time, there were a millions more Central Valley salmon being harvested each year in sport and commercial fisheries along the coast and rivers of the Central Valley. Improvements in salmon management in the decade of the 1990s by the Central Valley Project Improvement Act, CALFED, and other programs had paid off handsomely with strong runs from 1999 to 2005. New and upgraded hatcheries, along with trucking hatchery smolts to the Bay, significantly increased harvest and escapement to spawning rivers.

Figure 1. Central Valley salmon runs from 1975 to 2016 including fall, late fall, winter, and spring runs. Source of data: CDFW GrandTab.

By 2008-2009, escapement had fallen by over 90% to a mere 70,000 spawners of the four races of salmon.  Fishery harvests were greatly restricted by 2008.  The winter run, the most threatened of the four runs fell from 17,296 to 827 spawners in just five years.  Drier years from 2001-2005, poor ocean conditions in 2004-2005, record-high Delta water diversions, and the 2007-2009 drought were contributing factors in the declines.  Impacts to coastal communities and the fishing industries were severe.

Extraordinary recovery measures included closing fisheries and trucking most of the hatchery smolt production to the Bay or Delta.  Federal salmon biological opinions (2009, 2011) limited winter-spring water-project exports from the Delta.  Hundreds of millions of new dollars were spent on habitat and fish passage improvements in the Valley to increase salmon survival and turn around the declines in runs.  A look at Figure 1 indicates that these efforts proved effective in limiting run declines from the 2012-2015 drought compared to the 1987-1992 and 2007-2009 droughts.

However, the prognosis for the future is again bleak, especially for wild, naturally produced salmon.  The consequences of the 2012-2015 drought  have not fully played out.  Once again, projected runs are low, and harvests are likely to be restricted.  Actions are needed to minimize long-term effects and to help bring about recovery of wild salmon productivity and fisheries in general.

Actions for 2018:

  1. Reduce harvest: Sadly but necessarily, the Pacific Fisheries Management Council and states are likely to take this first step of– restricting the 2018 harvest in the ocean and rivers to protect wild runs.
  2. Improve spawning, rearing, and migrating conditions: Sadly, this past year’s rearing and migrating conditions in the Sacramento River were unnecessarily compromised.   Water temperature at Red Bluff reached above the 56oF prescribed in the biological opinion and Basin Plan.  The higher temperatures resulted from low Shasta Reservoir releases (less than 5000 cfs – Figure 2) despite a virtually full Shasta Reservoir.  The low flow and higher water temperatures likely affected salmon egg incubation, rearing, and emigration-immigration success.  Reservoir releases will be necessary to meet flow and temperature targets in all Central Valley rivers and the Delta.
  3. Limit Delta exports: Delta exports this past spring reached unprecedented highs not seen in recent decades, resulting in high salmon salvage rates at the Delta fish facilities (Figure 3).1 With high water supplies from this past wet water year 2017, there will be high exports again unless there are some constraints.  If anything, winter-spring exports should be reduced to allow salmon to recover.  April-May exports should be reduced, like they were in the 1990’s and 2000’s, to 1500 cfs.

Near term actions over the coming year:

  1. Transport hatchery smolts to Bay: The transport of millions of fall-run smolts from state hatcheries on the Feather, American, and Mokelumne rivers to the Bay provides higher rates of escapement and contributions to the fishery and low rates of straying.  Barge transport to the Bay offers potentially lower rates of predation and straying for federal hatcheries near Redding.
  2. Raise hatchery fry in natural habitats: Recent research indicates that rearing hatchery fry in more natural habitat conditions increases growth rates, survival, and contributions to escapement and fisheries.  Raising hatchery fry in rice fields is one potential approach.
  3. Restore habitats damaged by recent record high flows in salmon spawning and rearing reaches of the Central Valley rivers and floodplains: In nearly every river, habitats were damaged by the winter 2017 floods, requiring extraordinary repairs and maintenance to ready them again to produce salmon.
  4. Take further actions to enhance flows and water temperatures to enhance salmon survival throughout the Central Valley: Actions may include higher base flows, flow pulses, or simply meeting existing target flow and temperature goals.

In conclusion, managers should take immediate actions to minimize the damage to salmon runs from the recent drought and floods, using this past year’s abundant water supply.  They should avoid efforts to exploit the abundant water in storage for small benefits to water supply at the expense of salmon recovery, and should make every effort to use the water in storage for salmon recovery.

Figure 2. Upper Sacramento River flows and water temperatures in May 2017. The target water temperature for Red Bluff is 56oF. Source of data: USBR.

Figure 3. Export rate and young salmon salvage at South Delta federal and state export facilities in May 2017. The target export rate limit for May should be 1500 cfs. Source of data: USBR.

December 2017 – Risks to Salmon

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With a potentially record-low rain total for December, the federal and state water projects are cutting reservoir releases but keeping up exports from the Delta, causing great peril to Central Valley salmon.  Figure 1 summarizes Delta conditions as of mid-December.

Figure 1. Major Delta net daily flows (cfs) in mid-December 2017. Map source: USGS. Data sources: USGS and CDEC.

For juvenile winter run, spring run, fall run, and late fall run Chinook salmon migrating down the Sacramento River, the risk is obvious.  With nearly 40% of Sacramento River inflow diverted at Georgiana Slough and another 30% diverted at Threemile Slough, less than half of the Sacramento River’s inflow to the Delta is reaching the Bay.  Of the total Delta inflow, only 45-50% is reaching the Bay.  Nearly all the San Joaquin River Delta inflow is being exported.

Assuming that the young salmon split with the flow, 60% of Sacramento fish are being diverted to the central Delta and near 100% of the San Joaquin fish are lost to the interior Delta.  With winter run and late fall run juvenile salmon from the Sacramento River moving into the Delta during the late November storms (Figure 2), there is a high risk that the diverted fish will be lost in the interior Delta.  Soon, spring run and fall run fry salmon will be moving into the Delta.

Under the conditions in the “Reasonable and Prudent Measures” required by the National Marine Fisheries Service’s Biological Opinion (BO) for the operation of the state and federal water projects, exports should be reduced when “large numbers” of juvenile salmon begin entering the Delta (Figure 3).  The finding that there are “large numbers” is based on monitoring of juvenile salmon at Knights Landing and Sacramento.  Peak catches in the past month were 3-7 per day (Figure 2).  This does not meet the level of 10 per day under which the BO would trigger reducing exports.   However, the trigger dates from a time when the Sacramento River was producing 6 to 10 times more  juvenile winter run salmon.  In the last four years, juvenile production of winter run in the upper Sacramento River near Redding has been at record low levels of 300,000 to 500,000, compared to 3.3 million in 2009 when the BO was published.   “Large numbers” today are understandably smaller than they were eight years ago.

Exports should be reduced immediately until outflow to the Bay increases dramatically.  January BO limits will require Old and Middle River (OMR) flows near the south Delta export pumps to be no more negative than 5000 cfs.  With December OMR flows in excess of -9000 cfs (Figure 4), exports should be reduced now to limit OMR to -5000 cfs or lower per BO Action IV.3 through the remainder of December.

 

Figure 2. Catch of unmarked older Chinook juveniles (likely winter run and late fall run) at Knights Landing and Sacramento in fall 2017. Data from CDFW and USFWS surveys as reported by www.cbr.washington.edu/sacramento/

Figure 3. Excerpt from p. 652 of NMFS BO 2009.

Figure 4. OMR flows in south Delta. Source: https://www.usbr.gov/mp/cvo/vungvari/OMR_Dec2017.pdf .

WaterFix USFWS Biological Opinion Conclusions on Delta Smelt

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The US Fish and Wildlife Service’s biological opinion (USFWS BO) on the proposed “California WaterFix” (Delta Twin-Tunnels Project or CWF) concludes that the CWF will not jeopardize protected Delta smelt in the Bay-Delta.  In this post, I address the conclusions in the USFWS BO on the potential effects of WaterFix on Delta smelt.  This is another post in a series of posts on the WaterFix.

BO conclusion, p. 252.

Comment: The north Delta diversions (NDD) will increase tidal flows and upstream reverse flows below the NDD intakes. Adult smelt will migrate further upstream on their spawning run on average than they can under existing conditions. Thus, their likelihood of spawning nearer the NDD is greater. There would be more smelt spawners diverted from the Cache Slough area to the Sacramento River upstream of Cache Slough. The only impediment to such upstream movement and to spawning upstream of the project area would be loss to impingement or predation at the NDD diversion intakes. These effects would be significant risks to the population.

BO conclusion, p. 258.

Comment: These analyses did not take into account reduced freshwater inflow into the interior, central, western, and south Delta because of the diversions at the NDD intakes. South Delta exports would remain similar to existing constrained spring exports (~6,000 cfs) and high summer exports (no NDD exports). With less inflow to the lower Delta, the Low Salinity Zone in the lower Sacramento and San Joaquin channels would be expected to be further upstream, and entrainment potential from False River and lower Old River would be greater. Delta outflows would be lower, especially in drier years. Specified summer operations focused on south Delta exports would continue existing high summer risk to smelt and their habitat, especially if more spawning occurs in the lower San Joaquin River channel. Lower freshwater inflow will lead to higher salinities and warmer spring-summer Delta conditions, to the detriment of Delta smelt. Existing high summer impacts to Delta smelt would increase because of the more-upstream springtime distribution of smelt.

BO conclusion, p. 262.

Comment: The removal of a significant portion of freshwater inflow at the proposed NDD will not improve “transport flow function”. OMR effects will intensify with the LSZ further upstream in the lower San Joaquin River channel. The amount of smelt pulled through Three-Mile Slough and the amount transported tidally in the lower San Joaquin River from Antioch to Jersey Point via False River will increase. If OMR will not change in April-May, the primary smelt larval period, then larval impacts will be much worse without the fresh water diverted at the NDD.

BO conclusion, p. 262.

Comment: The 25oC restriction will come much earlier in spring without the freshwater inflow that is removed at the NDD. The change in LSZ position (more upstream) and water temperature (higher) will be generally detrimental to Delta smelt survival.

BO conclusion, p. 263.

Comment: Based on such past commitments and the performance of Reclamation and DWR, this one must also be taken with a grain of salt.” Without a clear understanding of factors affecting Delta smelt, as exemplified in this assessment, it is unlikely that the USFWS could protect Delta smelt under WaterFix operations.

BO conclusion, p. 272.

Comment: Water Year 2017 was the second year since the 2008 BO RPA on Fall Wet Year X2 came into play. In 2011, its application appeared to have positive effects.1 Yet in September 2017, the USFWS approved the provision’s removal. How are we to believe the commitment to employ the RPA in the future?

BO conclusion, p. 274.

Comment: The reduction of freshwater inflow to the Delta below the NDD will move the low salinity zone (LSZ) upstream and contract its size (volume and surface area). This will have serious adverse effects on smelt and their critical habitat.

BO conclusion, p. 274.

Comment: Reduction of freshwater inflow into the Delta can increase Delta water temperatures several degrees, to the detriment of smelt survival. Not only are water temperatures increased by lower net flows, but the LSZ is warmer when it is located further upstream from the Bay and its cooler air temperatures.

BO conclusion, p. 298.

Comment: Recognizing the uncertainty is no excuse for approving the proposed action (PA). There are no guarantees that predicted effects “will likely not be realized” or that future actions will protect smelt. It is more likely that recovery of Delta smelt will be further from reality with WaterFix.

More on Fall X2 Adaptive Management

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In an October 11 post, I discussed the state of California’s decision to maintain fall Delta outflow to the Bay (Fall X2). The 2008 Delta Smelt Biological Opinion (BO) requires that the State Water Project and the Central Valley Project keep the low salinity zone (X2) at km 74, near Chipps Island, in the fall of wet years. In early October, 2017, Reclamation and DWR requested that the fisheries agencies waive this wet year requirement to allow greater south Delta exports. The US Fish and Wildlife Service approved. But several days later, the California Department of Fish and Wildlife found that the action did not comply with the California Endangered Species Act, and the California Department of Water Resources reduced its south Delta exports to maintain Fall X2 compliance.1

To help the state maintain compliance, Reclamation began weekday closings of the Delta Cross Channel (DCC) (Figure 1), opening the DCC only on weekends to facilitate boat travel (Figure 2). Closure of the DCC forces more of the Sacramento River flow down the north Delta channel (Figures 3 and 4) repelling salt intrusion in eastern Suisun Bay near Collinsville (km 81) (Figure 5). The closure occurred 10 to 12 weeks earlier than normal (usually December 15), a highly unusual and provocative manipulation of Delta hydrodynamics. Its continued application after November 1 changes the hydrodynamic effects. Now that the Fall X2 requirement has expired, Delta outflow is lower and exports are higher. Under these conditions, DCC closure contributes to greater salinity intrusion into the central Delta via the lower San Joaquin channel and False River, moving Low Salinity Zone and Delta smelt back toward the central Delta.

DCC closure also helps more Mokelumne River adult salmon better hone in on their home river by keeping Mokelumne water out of the Sacramento channel near and below the DCC.2 However, Sacramento River salmon that enter the Mokelumne forks when the DCC is open on weekends would be blocked and delayed when the DCC is closed during the week. Closing the DCC also reduces San Joaquin channel net freshwater flows (Figure 6), which may hinder migrations of Sacramento, Mokelumne, and San Joaquin river adult salmon migrating up the San Joaquin channel of the Delta.

A likely upside of this unusual manipulation of cross-Delta freshwater flow is that it serves to keep the Sacramento River channel of the Delta fresher, which is part of the intent of the Fall X2 requirement. This action has minimal cost to reservoir storage and Delta exports, and it reduces straying of returning Mokelumne River hatchery salmon. On the downside, these DCC operations disrupt Delta hydrodynamics and water quality, move the Low Salinity Zone into the central Delta threatening Delta smelt survival, and interrupt salmon migrations in the Sacramento and San Joaquin rivers. It is likely that the Delta’s adaptive managers neither monitored nor assessed these potential downside ramifications.

Figure 1. Location of Delta Cross Channel in north Delta. (Base map from CDEC)

Figure 2. Reclamation began weekday closure of the Delta Cross Channel in mid-September (flow values are 0 on seven day intervals).

Figure 3. Weekday closure of the Delta Cross Channel in mid-September increased net flow downstream of the DCC in the Sacramento River channel below Georgina Slough.

Figure 4. Weekday closure of the Delta Cross Channel in mid-September increased net flow downstream of the DCC in the Sacramento River channel at Rio Vista.

Figure 5. Weekly closures of the Delta Cross Channel helped to maintain Fall X2 below Collinsville (km 81) through October in 2017.

Figure 6. Sporadic closure of the Delta Cross Channel reduces net freshwater flow in the lower San Joaquin channel in the central and western Delta.

Further Thoughts on the California WaterFix

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The Metropolitan Water District of Southern California, commonly known as MWD, recently released a series of information papers on the California WaterFix (Delta Tunnels).  In this post, I further address MWD’s “assessment” of what will happen to the Bay-Delta environment and fish community if the WaterFix is built and operated.  Excerpts from MWD’s papers and my comments follow.

WaterFix Objectives

California WaterFix proposes a strong operations plan based on sound, collaborative science and adaptive management to meet the following objectives:

  • Improve water supply reliability
  • Enhance ecosystem fishery habitat throughout the Delta
  • Allow flexible pumping operations in a dynamic fishery environment
  • Improve export water quality
  • Respond to climate change risks
  • Reduce seismic risks

Comment:  The proposed plan is unsound, not science-based, with no operations or adaptive management plan.  The WaterFix will wreak havoc on the Central Valley, Bay-Delta ecosystem.  That havoc will further water wars, not reliability.  Fishery habitat that depends on freshwater input will get less of it.  This will make the Bay-Delta warmer, saltier, more polluted, and more subject to the rigors of climate change.  Southern California will take the fresh clean Sierra water, leaving behind new burdens on the Bay-Delta.

Record Exports

State Water Project and Central Valley Project operations have been, and continue to be, affected by regulations that seek to change flow regimes in the Delta by setting rules for outflow variables. This has decreased operational flexibility and reduced exports to 25 million Californians who receive water from the SWP and CVP south of the Delta and millions of acres of irrigated farmland.

Comment:  Woe be it to saving some water for the rivers, Delta, and Bay.  Exports have increased each decade since the 60’s, when the SWP was built.  Delta export records were set in the 2000’s, reaching above 6 million acre-feet, only to be further eclipsed in 2011 and nearly so in 2017.  Relaxed outflow and salinity regulations in the 2012-2015 drought decimated fisheries and brought salt levels to the Delta not seen in four decades.  Such low flow and higher salinity conditions would be the new norm under the WaterFix.

Protecting Flows in the Delta

A more natural flow direction in the Delta during critical fish protection periods will increase water supply reliability and minimize reverse flows. North Delta diversions, fish screen designs, bypass flow criteria and real time operations will be managed to limit effects on listed fish species.

Comment:  Flow direction will not change – continued South Delta exports will still cause negative Old and Middle River, Jersey Point, False River, Threemile Slough, and Prisoners Point flows, but with less inflow from the North Delta.  There are no non-critical fish protection periods.  Adding more diversion will not protect fish.  The new North Delta fish screens will not protect fish1.  Bypass flow criteria will not repel salt or protect young fish from increasing diversions and greater tidal reverse flows when they migrate through the Delta.  Real-time operations have been around for a long time, and while they have protected water supply quantity and quality, they rarely have protected fish.

New Fish Habitat Benefits

Some of the benefits of the fishery habitat that will be created and restored include:

  • Improved habitat conditions along important juvenile salmon migration routes
  • Restored tidal and non-tidal wetlands, and native riparian forest habitat
  • Increased food production, spawning and rearing areas
  • Natural refuge from predators and changing climate conditions
  • Improved connectivity between existing areas of natural habitat

Comment:  The only changes in habitat that were not already required and planned are (1) the over two miles of perforated steel walls along the banks of the Sacramento River in the North Delta, and (2) the considerable reductions in freshwater flow into the Delta and Bay.  Most of the habitat improvements in the now defunct Bay Delta Conservation Plan or BDCP are not included in the WaterFix.

Changes in Delta Export Regulations

The SWP and CVP facilities have long been impacted by changing regulations governing both projects’ diversion facilities in the south Delta. On average, D-1641 has reduced SWP and CVP diversions and increased Delta outflows to the San Francisco Bay by about 300,000 acre-feet a year as compared to the SWRCB’s prior requirements.

Comment:  Since D-1641 rules came online in the mid-1990’s, exports have continually increased, including record levels above 6 maf in 2005, 2006, 2011, and 2017.  Water year 2012, a below-normal water year, was not far behind at 5.8 maf.  Even below-normal 2010, after three critical water years, saw 4.8 maf of exports, equivalent to wet year exports in 1998 and 1999.  Yes, exports were down in the 2007-2009 and 2013-2015 droughts, but were not unlike the 1977 and 1990-1992 drought levels.

Compounding the impacts, the biological opinions have decreased diversions and increased outflows by about another 1 MAF a year (Source: MBK Engineers and HDR “Retrospective Analysis of Changed Central Valley Project and State Water Project Conditions Due to Changes in Delta Regulations,” January 2013). 

Comment:  If this were the case, how is it that a record 6.7 maf of Delta exports in wet year 2011, and 5.8 maf in below-normal 2012 were possible under the 2008-2009 biological opinions?  The new restrictions, though real on paper, did not restrict actual exports, only the future capacity of exports.  The WaterFix plan would eliminate such constraints on total exports.  Though MWD, DWR and the Bureau of Reclamation say they would not increase exports, can we really take them at their word with WaterFix’s 40% increase in export capacity?

The increased Delta requirements and export constraints have further affected SWP and CVP operations by decreasing operational flexibility and increasing water supply vulnerabilities during dry conditions. This, in turn, reduces project reservoir storage, water deliveries, and supply reliability. Figure 1 illustrates the decrease in average SWP and CVP delivery capability over time due to additional regulatory requirements. As shown in the figure, over a period of a little more than 25 years, the export capability of the two projects has been reduced by over 3 MAF per year. California WaterFix is intended to reverse this downward trend.

Comment:  Again, real exports have increased year after year as new capacities south-of-Delta have come online.  Reservoir storage has been more aggressively used to the detriment of long-term water supply.  Restrictions applied have done more to deter future exports; thus the need for the WaterFix.

North Delta diversions, fish screen designs, bypass flow criteria and real time operations will be managed to limit effects on listed fish species.

Comment:  The permitting agencies have set low, unattainable, and arbitrary limits on effects (e.g., 5% loss of fish passing north Delta intake screens).  They contend that all the Valley flow and export “valves/knobs” and infrastructure operational options (e.g., gate opening/closure, air bubble screens, etc.) can be “managed” to protect listed fish.  Even if that were possible, this does not account for all the unlisted fish including striped bass, American shad, splittail, lamprey, threadfin shad, fall run salmon, native minnows, and pelagic habitat.

Adaptive Management

An Adaptive Management Program would be implemented through a collaborative process with regulatory agencies, project operators, and water contractors. This would provide a structured science process to develop adaptive means of improving conditions for both the ecosystem and water supply. Project operations that respond to real-time Delta conditions would also advance these objectives and provide greater certainty for water deliveries.

Comment:  The foxes, wolves, and hawks will be there to ensure a continuous supply of chickens from the henhouse.  Past adaptive management has focused on protecting water deliveries.

Biological Opinions

These biological opinions determined that California WaterFix as proposed would neither jeopardize the continued existence of species listed under the federal Endangered Species Act (ESA) nor destroy or adversely modify critical habitat for those species.

Comment:  What happened between the draft and final Opinions?  The agencies responsible for the application of federal and state Endangered Species Acts have taken out their false teeth and set them on that beautiful nightstand called adaptive management.

Exporting Water from North Delta

Over a period of a little more than 25 years, the export capability of the two projects has been reduced by over 3 MAF per year. California WaterFix is intended to reverse this downward trend.

Comment:  Again, export records have been achieved in all water year types in the decades of the 2000’s.  Yes, D-1641 water quality standards, listed fish biological opinions, and operation permits have placed new rules on “capability” but have done little to appease the appetite for water that the two projects have no right to.  Now they want new rights to further wet their thirst.

Comment:  This figure shows a commitment to constraint (subject to change under “adaptive management”) at the proposed north Delta diversion.  What it does not show is the ability to increase north Delta exports by increasing reservoir releases or the ability to export water from the south Delta.

Operating Rules

The initial operating criteria for California WaterFix includes regulatory requirements that were established through D-1641, the 2008 and 2009 biological opinions for existing water project operations, and new criteria developed through California WaterFix’s environmental permitting process.

Existing regulatory requirements in the assumed initial operating criteria include:

  • Salinity standards;
  • Spring and fall outflow to manage the overall salinity gradient (known as “X2”);
  • Cross Channel Gate, Suisun Marsh Gate, and temporary agricultural barrier operations;
  • Limits on SWP and CVP diversions to manage flows in Old and Middle Rivers and entrainment;
  • Rio Vista flow.

New regulatory requirements in the assumed initial operation include additional limits on SWP and CVP diversions (i.e., Old and Middle River flow reversals) and flow (i.e., spring outflow, North Delta Diversion Bypass flow). California WaterFix also includes a permanent operable gate at the Head of Old River for fish migration protection and criteria for its operation.

Comment:  All of these rules have been weakened in recent years to maintain water diversions.  All the “rules” for the existing projects operations are in the process of review and face possible change because the ecosystem and listed fish have not been adequately protected.  The proponents of WaterFix have not proposed or evaluated new rules for existing infrastructure and operations or for new infrastructure and operations if WaterFix were constructed.

Water Transfers

The flexibility provided by California WaterFix also improves the capability of moving water transfer supplies across the Delta. The increased conveyance and operational flexibility would significantly increase the amount of available capacity to accommodate the movement of water transfers across the Delta and the SWP and CVP system.

Comment:  Water transfers have significant potential impacts.  Existing constraints would be removed.

Water Quality Standards

The variable split between north and south diversions would allow a flexible and improved approach toward compliance with flow and salinity standards. For example, if salinity increased on the lower Sacramento River, the SWP and CVP could opt to increase diversions in the south Delta and thereby allow greater flow down the lower Sacramento River. In contrast, if salinity increased on the lower San Joaquin River, the SWP and CVP could decrease water diverted in the south Delta and increase diversions in the north Delta, thereby increasing flow in the lower San Joaquin River and south Delta. The flexibility offered by this example would limit reverse flows in the central Delta near Jersey Point, which in the past have drawn saltier water from the San Francisco Bay into the central Delta.

Comment:  None of these assumptions are true.  Lower Sacramento River flows are affected by south Delta diversions.  North Delta diversions would affect Jersey Point reverse flows on the lower San Joaquin River because less water would pass through Georgiana Slough and the Delta Cross Channel. The Delta Outflow Index would remain the same whatever the split.

With California WaterFix, the SWP and CVP would continue to meet existing Delta water quality, fishery objectives, and any future regulatory requirements. Increased diversion flexibility afforded through the approval of California WaterFix would only enhance the capabilities of SWP and CVP projects to meet existing Bay-Delta requirements. Because California WaterFix can take advantage of opportunities to divert and store wet-period storm flows and allow for south Delta diversions in drier periods, in-Delta water quality can be better managed. As a result, the proposed California WaterFix operations would continue to be as protective, if not more, of existing beneficial uses.

Comment:  How does MWD know what future requirements will be, let alone whether the Projects can  meet them or the water supply cost of meeting them?  Allowing continued south Delta exports in dry periods has been the heart of Bay-Delta problems for many decades.  Most wet-period storm flow is stored in Valley reservoirs; that remaining has been allocated for the Bay.  There are no proposed changes in infrastructure or operations that would make WaterFix more protective of existing beneficial uses.