Tag Archives: State Water Project

Oroville, Again

A lot has happened at Lake Oroville in the three days since I posted an introduction to the State Water Project (SWP), to put it mildly.

At the time of that writing, Saturday afternoon, the lake level was at 902.02’, with water flowing over the emergency spillway sill at 901’, and releases from the damaged controlled spillway at 55,000 cubic feet per second (cfs). The lake level peaked at 902.59’ at 3am Sunday morning and then began to slowly decline. At 11am Sunday, the California Department of Water Resources (DWR) reported that flow over the emergency spillway had peaked at 12,600 cfs and since declined to 8,000 cfs, with the situation stabilized. At 4:40pm Sunday, an emergency evacuation was ordered, with the emergency spillway predicted to fail in as soon as an hour.

This photo from February 11 shows the emergency spillway not long after water began to flow over it. Note the roadway in front of the spillway. Very little erosion has occurred in this photo, though some channelization is visible bottom center.

This photo from February 12 shows the emergency spillway with erosion having progressed further uphill. Note the road has been washed out, and the channel has deepened and worked its way uphill.

Faced with this situation, DWR increased the releases from the controlled spillway, to try to save the emergency spillway. Releases were increased to 100,000 cfs, and after a few very tense hours, the lake level dropped below 901’ at about 8pm Sunday. Water stopped flowing over the emergency spillway, and the erosion stopped.

This photo from February 13 shows the damage to the emergency spillway. Note the people for scale. I do not know which channel was of the most concern but the large channel near the washed out road and white truck was not the closest to the emergency spillway sill. Top right, just left of the far end of the concrete spillway, are two workers in yellow vests standing by the channel that got closest. This photo shows a closer view, with that channel just behind the workers.

It’s obviously a huge relief that the lake level is below the emergency spillway and that the structure survived. It’s also a huge relief that the damaged controlled spillway has been able to maintain 100,000 cfs releases, which as of this writing (9pm February 14, 2017) have lowered the lake level to 883.60’, over 17’ below the surface of the emergency spillway sill.


This has allowed DWR to being making emergency repairs to the emergency spillway, in case it must be used again. This photo shows placement of rock in the channel that got closest to the emergency spillway sill. DWR also posted two videos, one from yesterday and one from today, showing the repair work. Emergency evacuation orders have been lifted, but residents are to remain vigilant under an evacuation warning, in case the situation changes.

It is very good news indeed that the emergency spillway survived. However, it is only mid-February and we still have a lot of winter to go, followed by spring runoff when an above-average snowpack melts. In another stroke of good fortune, the National Weather Service (NWS) Sacrament office is predicting the next storm, for Wednesday night and Thursday, to have lower snow levels (5000’-6000’) than originally expected (7000’-8000’). This will keep the precipitation as snow, rather than rain and melted snow that will immediately run down into Lake Oroville. This will allow DWR to keep lowering the lake level to create flood storage for the spring, and keep making repairs on the emergency spillway. Another series of storms is expected for Monday and Tuesday next week, but with snow levels between 3500’-5500’.

After the snow is gone, there are going to be a lot of questions to be answered. I’m not going to litigate the decisions made by DWR here; I’m sure there will be plenty of people to do that soon enough. I also want to say that I have great respect for the many DWR engineers and workers, the Butte County Sheriff, and many other public employees and safety officials that have worked hard to ensure public safety, and have had to make many extremely difficult decisions about how to proceed in a dangerous and dynamic situation.

As a civil engineer, things like this really hurt. Like many civil engineers, I went into this business because I believe it is a profession where I can put my natural skills to work in a way that improves people’s lives. I never want to see our works fail or put people at risk.

This is going to be a case study for future civil engineers, for that is what we must always do when something doesn’t work the way it should: ask ourselves why, figure out what went wrong, learn from it, and improve our designs and processes so that we increase public safety and public benefits in the future. I think there will be four main questions to be researched here:

  • What was the proximate cause of the damage to the controlled spillway?
  • Why was the emergency spillway damaged so critically by relatively modest flows (12,600 cfs) relative to its capacity (several hundred thousand cfs)?
  • What was the decision making process after the initial damage to the controlled spillway? Was all relevant information available to decision makers?
  • Was information available before the crisis that should have led to corrective actions, and if so, what stopped corrective actions from being taken?

In short there are several distinct things here: pre-crisis actions, controlled spillway damage, emergency spillway damage, and crisis management.

Again, none of this is to question the hard-working people who are doing everything they can to mitigate the crisis and have faced very difficult decisions. As engineers, we must seek to improve our understanding of our designs, how the natural world interacts with our designs, and how our decisions and processes affect those systems. My heart goes out to anyone affected by this situation, and I sincerely hope that we, as Californians, can pull through this and use the lessons to help make our state a better place.

The State Water Project: An Introduction

If you follow this blog’s twitter account, you know that engineering & water twitter has been closely watching the situation at the Oroville Dam in northern California. Many people know, conceptually, that much of the water we use in SoCal comes from northern California, but are not familiar with Oroville or the State Water Project. So, here’s a brief introduction to what the State Water Project (SWP) is, what it does, and what’s happening at Oroville now.

The SWP is an important source of water for SoCal, and Lake Oroville is the main reservoir. While popular conception hold that LA’s water comes from the east Sierra and Owens Valley via the LA Aqueduct, over the last 5 years, that facility has only delivered 29% of LA’s water. The SWP is the largest supplier of water to the city of LA, with 48% of LA’s water over the last 5 years coming from the SWP. So what happens at Lake Oroville is of interest to, well, anyone south of Lake Oroville.

The State Water Project: California Dreaming… Big

Everyone knows the split nature of California’s climate: the north is wetter, the south is drier. However, many people and much of the best farmland are in southern California. Over half of the state’s population lives in relatively dry climates south of the Transverse Ranges, which separate the southern quarter of the state from the rest. In addition, California experiences wide swings in annual rainfall, with droughts and floods often following on each other’s heels. In fact, 2014-15 was the driest water year in state history, but 2016-17 may prove to be the wettest.

This situation naturally led to the desire for civil engineering improvements to both prevent devastation from flooding in wet years and store water for human use during drought years. The SWP was conceived to help meet these goals. The map below shows the main components of the SWP.


The major components of the SWP are:

  • Oroville Dam: this dam is located on the Feather River, which drains a portion of the northern Sierra Nevada, and is the source of water for the SWP. Lake Oroville can store up to 3.5 million acre-feet of water, making it the second largest reservoir in the state after Lake Shasta. One acre-foot of water is enough water to cover an acre of land one foot deep – about 325,000 gallons.
  • California Aqueduct: this aqueduct conveys water from the delta to users in central and southern California. Water released from Lake Oroville flows down the Feather River and Sacramento River to the delta. From there it is pumped south out of the Clifton Court Forebay.
  • San Luis Reservoir: this is a large off-line reservoir in the southern Central Valley that can store 2 million acre-feet of water. “Off-line reservoir” means that it is not located on a major river – it was created by damming an existing valley and filled with water from the California Aqueduct. The creek that formed the valley, San Luis Creek, would never carry enough water to fill the reservoir on its own.
  • Distributary aqueducts: these aqueducts carry water from the main California Aqueduct to water uses. These are:
    • North Bay Aqueduct and South Bay Aqueduct, which serve the East Bay area.
    • Coastal Branch, which serves San Luis Obispo and Santa Barbara Counties, including a connection to Lake Cachuma, Santa Barbara’s main water supply.
    • West Branch, which serves the Los Angeles area and includes Castaic Lake and Pyramid Lake, the lakes you see from the 5 when you drive through the Grapevine.
    • East Branch, which serves the Inland Empire and includes Silverwood Lake and Lake Perris.
    • Second San Diego Aqueduct, which connects Lake Perris to San Diego County.

Because of the complicated geography and politics of water in California, the SWP includes some water agencies that don’t even have a physical connection to the project. For example, the Desert Water Agency (DWA) and Coachella Water Valley District (CVWD) serve Palm Springs and the Coachella Valley, which have no connection to the SWP. The DWA and CVWD buy SWP water and then swap it with the Metropolitan Water District of Southern California (MWD SoCal) for water from the Colorado River. So DWA and CVWD pay for SWP water, which is delivered to MWD SoCal, and in exchange, MWD SoCal gives DWA and CVWD water from the Colorado River Aqueduct.

Construction on the SWP started in the early 1960s and the major components were done by the late 1970s, though construction on various pieces such as the East Branch Extension continues up to the present day. The SWP is just one legacy of the leadership of Governor Pat Brown, who for his investments in water infrastructure, freeways, and education ought to be known as the father of modern California.

Ok, So What’s Going on at Oroville?

Lake Oroville is a dual-use reservoir – it is used both to store water for human use and to capture water from torrential rainstorms and snowmelt to prevent devastating flooding downstream. Every such reservoir has its storage divided into conservation storage and flood control storage. Under normal conditions during the rainy season, the reservoir is not allowed to fill up beyond the conservation storage level, so that if a big rainstorm or snowmelt event happens, there will be enough capacity to prevent flooding. Reaching the top of conservation storage is like the gas light coming on in your car: it means you need to start looking for a gas station, because you don’t want to run out of gas before you start looking.

Early this week, a large winter storm hit northern California. The storm was warm, meaning that it had high snow levels (the elevation in the mountains where the storm changes from rain to snow), so much of the precipitation went into the rivers right away instead of adding to the snowpack in the mountains. The warm temperatures and rain also caused some of the existing snowpack at low elevations to melt and flow into the rivers.

On Tuesday, Lake Oroville was near the top of conservation storage, and with a large amount of water on its way to enter the lake, state water managers increased water flow through the controlled spillway on the Oroville Dam. A controlled spillway is a structure on a dam that has gates that can be opened and closed by motors, allowing the agency in charge to control how much water leaves the reservoir. The Oroville controlled spillway had a theoretical maximum capacity of 250,000 cubic feet per second.

However, as flows ramped up, a sinkhole appeared in the lower portion of the spillway, and water releases had to be stopped to allow inspection. After assessing options, it was determined that because of the large volume of water entering the lake, it was necessary to continue to allow water to flow through the damaged spillway to keep the lake from rising too quickly. Water flowing through the spillway has caused additional erosion, although yesterday and today the discharge appears less muddy. Hopefully, this is an indication that the channel has cut down to bedrock, and erosion has slowed down.

As water flows downhill, erosion will tend to cut back uphill. This is why Niagara Falls is at the head end of a long gorge; the falls have cut the gorge back upstream from the Niagara Escarpment since the end of the last ice age. It is critical that erosion on the controlled spillway at Oroville not be allowed to proceed uphill and damage the spillway gates, which would negatively impact the ability to control releases down the spillway. That is why the damaged spillway is only being allowed to operate at a reduced capacity.

Because inflow is currently greater than outflow, the lake level is rising. However, this is NOT a threat to the Oroville Dam itself, because there is an emergency spillway that the water will flow over first. The dam crest elevation is at 922’, while the emergency spillway sill is at 901’. The emergency spillway is an uncontrolled weir, so once the lake reaches elevation 901’ water starts to flow down the emergency spillway. This happened at about 8am this morning and as of 3pm February 11, 2017, the lake elevation is at 902.02’, so water continues to flow over the emergency spillway. In a noon press conference, the state announced that it expects this flow to continue for 36-56 hours.

The emergency spillway is an unlined, unimproved channel, which means water that flows over down it is just flowing over dirt, vegetation, and rocks. This means some erosion will occur and enter the Feather River downstream.

What’s Next?

Because it’s only mid-February, winter is only part way over, and more rain and snow storms may be on the way. The state will face challenges with water coming into the lake over the next few months as additional storms hit, and then as spring and summer temperatures melt the snowpack. At the moment, it does not appear there will be enough time to much in the way of repairs before more rain and snow arrive. Resource managers will face difficult decisions between increasing flow on the damaged spillway and allowing additional flows over the emergency spillway.

It’s important to emphasize that as of this writing (3pm February 11, 2017), there is no threat to the Oroville Dam itself, no flooding occurring downstream, and no imminent public danger. Everyone should pay attention to information from the California Department of Water Resources, the Butte County Sheriff, and the California Office of Emergency Services for updates on changing conditions.

After the rainy season and spring snowmelt is over, the state will face a busy summer construction season at Oroville, including repairs to erosion and/or improvements to the emergency spillway, and repairs to the existing damaged controlled spillway or replacement with a new controlled spillway.

Is the SWP the Same Thing as the Central Valley Project?

No, though they are related. The SWP is operated by the state of California, while the Central Valley Project (CVP) is operated by the federal Bureau of Reclamation. The main CVP components are:

  • Shasta, Trinity, and Whiskeytown Lakes in northern California, which store water for use in the Central Valley.
  • Tehama-Colusa Canal, which distributes water for use in the northern Central Valley.
  • Friant Dam and Millerton Lake on the San Joaquin River, and the Friant-Kern Canal, which distribute water from the San Joaquin River for use in the southeastern Central Valley.
  • Delta-Mendota Canal, which distributes water from the delta for use the San Joaquin River drainage basin below Friant Dam.
  • San Luis Canal, which is shared with the SWP, and distributes water for use in the southwestern Central Valley.


In addition, there are interconnections between the SWP and the CVP such that if the south Sierra has a very wet year, water from the Tulare Basin rivers (Kings, Kaweah, Tulare, and Kern Rivers) can be sent to the SWP.

What Are All Those Grey Squares on the SWP Map?

Curious readers may have noticed several reservoirs and other facilities on the SWP map shown in grey. These are facilities that were proposed as part of the SWP but never constructed.

The undeveloped facilities in northwestern California are of the greatest consequence. The project as originally proposed included dams on the Klamath River and Eel River, which would have created the Ah Pah Reservoir and the Dos Rios Reservoir. At 15 million acre-feet and 7.5 million acre-feet, respectively, each of these reservoirs on their own would have dwarfed Lake Shasta and Lake Oroville. These facilities would have been located in the wettest part of California. An additional reservoir, the Glenn Reservoir, would have been located east of the coastal mountains, with water directed there via tunnel from Dos Rios.


Since the Klamath and Eel Rivers are not currently connected to the SWP, these dams would have greatly increased the water available to the SWP. However, they would have destroyed some of California’s last free-flowing river segments, and would have had enormously negative consequences for fish and other wildlife. The large environmental impacts resulted in these projects being canceled, and they are unlikely to ever be revived.

The other two unbuilt large reservoirs are the Sites Reservoir and Los Banos Grandes Reservoir. The Sites Reservoir would be able to store between 1.2 million and 1.8 million acre-feet, with Los Banos Grandes adding another 1.7 million acre-feet. Together, they would equal another Lake Oroville of off-line reservoir storage, increasing SWP storage by over 50%. Since they would be off-line reservoirs, not located on main rivers, the impact of these facilities might be less.

The last major unbuilt piece of the SWP is the Delta Peripheral Canal, or as we know it today, the Delta Peripheral Tunnel. The purpose of this facility would be to channel water from the Sacramento River (released from Lake Oroville, Lake Shasta, or the Sites Reservoir) around the delta to the pumping facilities that send the water south via the California Aqueduct. This would reduce the environmental impact on the delta and increase the reliability of SWP water deliveries.

With climate change possibly making droughts and floods more likely, and causing precipitation to fall as rain instead of snow, there may be renewed interest in the Sites Reservoir, Delta Peripheral Tunnel, and maybe even Los Banos Grande Reservoir.

Call Me Mulholland

Warning: this is a long, subjective post, and might be a waste of your time. If you’re looking for real analysis, maybe just sit this one out.

Today is the 100th Anniversary of the dedication of the Los Angeles Aqueduct. Conceived of and designed by William Mulholland, the aqueduct (along with the southern transcontinental railroads and the ports) is one of the definitive pieces of LA infrastructure. The city simply would not exist the way it does today without the aqueduct.

So, in celebration of the aqueduct, let’s take a look at LA’s existing water sources, conservation efforts, and potential expansions.

Los Angeles Aqueduct (Owens Valley and Mono Basin)

The genius of the LA Aqueduct is its simplicity. Water from snowmelt in the East Sierra used to run into the Owens River and then into Owens Lake, an endorheic lake south of Lone Pine. Mulholland realized that the river could be diverted to flow, by gravity, to the San Fernando Valley using nothing but ditches, siphons, inverted siphons, and the like. Thus, the LA Aqueduct is one of LA’s best sources of water in terms of carbon footprint, since there is no need to pump the water to get it to the city. However, the diversion of the river resulted in the desiccation of Owens Lake.

Later, the city extended the system north to the Mono Basin using tunnels to get through the volcanic rocks that separate the basin from the Owens Valley, and constructed Lake Crowley for water storage and flood control. The diversion of the creeks feeding Mono Lake caused the water level in the lake to begin to fall, and it appeared that Mono Lake might suffer the same fate as Owens Lake. The formation of the Mono Lake Committee in 1978, resulting in lawsuits that were finally settled in 1994, spared Mono Lake from following in the footsteps of its larger, fresher neighbor to the south. As a result, today very little of LA’s water comes from the Mono Basin; at the time of this writing, the lake elevation is 6380.1’, still short of the target elevation of 6392’.

The city’s water sources in the Owens Valley have also come under pressure, due to demands for dust control from the Great Basin Air Quality Board (GBAQB). The dry lake bed is a significant source of dust, though certainly not the only one in a dry desert valley. Counterintuitively, dust is a problem because the water table remains close to the surface, which encourages salts and small particulate matter to migrate upwards to the surface, where they are picked up by the wind. GBAQB and LADWP have decided to address the dust problem by “rewatering” the lake bed, using a complex and expensive scheme of pumps and distributary equipment. This treatment is using almost half of the annual water volume that the aqueduct is capable of delivering.

I have a much dimmer view of the Owens Lake project than the Mono Lake controls. At the time the Mono Lake Committee was formed, the impacts to the lake ecosystem were just reaching a significant point. Much worse impacts to the brine shrimp and nesting birds were avoided by stabilizing and increasing the lake level. The city was able to adjust to the reduced flows with conservation efforts.

In contrast, Owens Lake has been dry for decades. Diverting water to the lake bed does not preserve lake ecosystems, because they are long gone. The salty environment is hard on pumping equipment, and rewatering is not the most cost-effective way to control dust on the lake bed. In fact, a cost-benefit analysis would likely show that almost any dust control measure does not make sense given that the primary beneficiaries are the 66 remaining residents of Keeler – a third of whom are over age 65, and 83% of whom are over age 45. Buying them out and focusing on dust control measures for times when the winds blow from the east (which is less common, prevailing winds are from the west) to mitigate dust generated by the lake in Lone Pine, Olancha, and Cartago (combined population about 2,500) would be much more logical.

The problem is that the Owens Lake project isn’t really about environmental benefits or controlling dust, it’s about settling old scores between the Owens Valley and Los Angeles. Residents of the valley are convinced that Los Angeles “stole” their water (I use scare quotes because the city bought the water rights). Grudges last for a long time, especially water grudges in the West, and depriving the city of water through legal mechanisms makes up for not being able to deprive the city of water by dynamiting the aqueduct. Meanwhile, the fate of other desert lakes in the West suggests that if the lake hadn’t been drained by Los Angeles, it would have been drained by agricultural interests.

Letting water and money needlessly vanish in the scorching Owens Valley sun is bad enough, but the Owens Lake project has significant negative effects on other parts of the system. It’s forced LADWP to increase water purchases from the Metropolitan Water District (MWD) via the Colorado River Aqueduct and the State Water Project (SWP) via the California Aqueduct. This results in using water sources that consume energy in being pumped over mountains on their way to Los Angeles, and creates needless conflict with other MWD and Colorado River users and with agricultural interests in the Central Valley.

The Owens Lake project needs to be completely reassessed. There is no point in wasting that water and throwing good money after bad. Remediation efforts should be based on achieving efficient results starting from present conditions, not wistful nostalgia and guilt for what happened in the past.

Colorado River Aqueduct

Mulholland was gone, ruined by the failure of the San Francisquito Canyon Dam in 1928, but the Colorado River Aqueduct was his conception too. Like the LA Aqueduct before, it caused some ill will with the locals in Arizona, who thought they should get the water. Phoenix and Tucson did get their water, eventually, with the completion of the Granite Reef Aqueduct, but in water law in the West, being first to the well counts for just about everything. Arizona’s and Nevada’s claims are now subservient to California’s, which means if the Bureau of Reclamation (USBR) is short of water, their deliveries will be cut first. Before rapid growth in places like Las Vegas and Phoenix, this wasn’t an issue, because Nevada and Arizona weren’t using their full allotments. But the day of reckoning is fast approaching; barring an above average snowpack this winter, cuts will be forthcoming in 2014 or 2015.

California’s share of water has been under pressure, too, from growth in places like San Diego. Unlike the LA Basin and IE, which at least have the LA Aqueduct and SWP, San Diego has no connection to water outside the MWD. Recently, this has led to the Imperial Valley selling some of its water to San Diego. Agricultural output can be maintained by switching to crops and varieties that use less water, and using more efficient irrigation systems.

Normally, that’s an all-around win, but in a twist of fate, agricultural runoff is the only thing maintaining the level of the Salton Sea. Troubled though it is, the Salton Sea is used by wildlife, and it can’t be allowed to dry up. If it were to dry, the pollution in the runoff that has accumulated would become airborne – making the problems at Owens Lake look small in comparison. The Salton Sea Authority was created to try to address this issue, but the money to execute their plan isn’t there yet. This might be a case where value capture is applicable – if you keep the sea from drying out, you really are adding value. Stabilizing the water level would also make lakefront property much more valuable; since the lake has no outlet, it is subject to considerable rises and falls in surface elevation as precipitation varies.

Really, the Colorado River is just about tapped out. Practically no users have surplus water. Las Vegas is so nervous about its sole water supply that it’s constructing a new intake from Lake Mead (lower than existing intakes, so that it will remain operable if lake levels drop) and building a pipeline hundreds of miles north into the Nevada desert to tap the meager water resources of the Basin and Range. There’s no water to be had here. California is lucky enough to have other sources. Arizona and Nevada will just have to adapt.

State Water Project

I have to say, as an engineer, the SWP is just waaay cool. Cruising up some world class highway engineering on the 5 through the Central Valley, looking out over endless farms and the gentle contours of the California Aqueduct and the Delta-Mendota Canal – that’s up there with kicking back on a whisper-soft high speed rail ride or hopping the world’s largest subway system, which didn’t even exist 20 years ago. Wait, sorry, engineering fantasies – what was I talking about?

The basic premise of the SWP is that water from the Feather River is stored at Oroville Dam, 450 miles north of LA. The water makes its way south via the Sacramento River, the Sacramento-San Joaquin Delta, and the California Aqueduct. Much of the water goes to irrigation in the Central Valley, but the aqueduct extends as far as Santa Barbara County (Coastal Branch), Castaic (West Branch), and Perris (East Branch). Water agencies as far away as Palm Springs participate in the SWP even though they have no direct connection (they swap MWD water for SWP water with agencies that connect to both). The SWP, along with the USBR’s  Central Valley Project (CVP), is what makes the Central Valley an agricultural powerhouse.

Like many of California’s water supplies, SWP deliveries have come under pressure as a result of some dry winters, increased demand, and environmental concerns. In this case, the victim is the delta smelt, which lives in the Sacramento-San Joaquin Delta. During dry years, low water flows in the delta result in the SWP and CVP pumps on the south side of the delta creating unusual currents, which appear to be correlated with declines in fish populations. Again, I’m generally in favor of trying to preserve threatened ecosystems like these (as opposed to environmental vanity projects like rewatering the long-dry lower San Joaquin River).

When there’s insufficient water to meet all SWP demands, someone’s deliveries have to be cut, which often means less water is available for agriculture in the Central Valley. Some water can be stored in the San Luis Reservoir (the largest off-line reservoir in the US) and some can be supplemented by groundwater pumping. Long-term reliance on groundwater pumping risks drawing down the aquifer, though evidence suggests that unlike the Ogallala Aquifer, there is some recovery of Central Valley aquifers during wet years.

Agricultural interests in the Central Valley (and Imperial Valley, for that matter) seem to get little sympathy in the state’s more urban areas, maybe because environmentalists tend to view irrigated agriculture unfavorably. In my opinion, this is unfortunate: lower agricultural output means significant hardship for some of the state’s most vulnerable workers. Much of the state’s irrigated acreage (the Sacramento Valley, Friant-Kern Canal, eastern San Joaquin Valley, and Imperial Valley) is irrigated by gravity, requiring little energy to operate. The projects that do require pumping (SWP, Delta-Mendota Canal) aren’t that bad since the Central Valley is pretty flat – the big energy requirements on the SWP come in to get the water over the Tehachapi Mountains, which is for urban users in Southern California.

The ability to use reservoir and groundwater storage to smooth out wet and dry years is a major advantage of California agriculture, which can stand up to droughts that ruin crops in the Great Plains and eastern US. The moderate California climate means crops aren’t subject to damaging freezing temperatures like other places. Hopefully, we can manage our water resources to maintain the competitive advantages of California farming.

Local Groundwater and Conservation Efforts

I won’t say much about efforts to develop local groundwater resources and promote conservation in the LA area other than to say I’m in favor of it. These efforts ease pressure on outside sources, and increasing the number of sources provides some system resiliency, e.g. if the East Sierra is having a banner snow year, we could use groundwater storage to save up some water for dry years.

Channeling My Inner Mulholland

Ultimately, this would be a pretty boring post if all I did was recap our existing water sources with a little commentary thrown in, and at 2,100 words, maybe you’ve already tl;dr’d it. But if you’re still with me, here’s two other potential water sources we could tap.

I don’t know if the finances would pencil out, but they would add a couple resources that could be used to take pressure off of existing resources. The goal would be to develop the resources with a minimum environmental impact, and blend sources every year so that no one resource is overused. The obvious issue is that once you’ve paid to build the infrastructure, the temptation is there to max out everything, and then when a drought hits, you’re screwed. So hey, maybe we build these, call it SWP2, turn everything west of Lancaster into another Imperial Valley, and go down in a blaze of glory when a long drought hits like so many desert irrigation civilizations before us. I propose, you decide.

Walker River

The East Fork of the Walker River is the logical last gasp in the East Sierra, just north of the Mono Basin. The headwater streams of the river pass pretty close to Conway Summit, which separates the Walker Basin from the Mono Basin. For the price of a short tunnel under the summit, you could build a diversion ditch to send some of that flow southeast to the Mono Basin. The West Fork of the Walker River is too far away, and the intervening terrain too mountainous, to make it practical to try to get anything out of that basin.

The terminus of the Walker River, Walker Lake, is not without its own issues due to local water diversions, and Nevada probably wouldn’t take too kindly to California trying to buy up all the water rights. This option would probably be a long shot, but maybe you could pitch it as a flood year only diversion. Precipitation in the Sierra can be irregular, and very heavy during El Nino years; the West Branch of the Walker River flooded badly in 1995, destroying parts of the 395. There could be a threshold snow water content for the snowpack that would allow some diversion during heavy snow years, and prevent flooding downstream on the Walker. The diversion ditch could connect into the Mono Basin Project pretty easily, thereby conveying the flow to Lake Crowley.

Delta Peripheral Canal and Northwestern California Rivers

The Delta Peripheral Canal was first contemplated as an actual canal during Jerry Brown’s first stint as governor; now, it’s been reconceived as a pair of bored tunnels to reduce environmental impacts to the delta, which makes canal a pretty significant misnomer. The point of the canal is to allow diversions from the Sacramento River to the SWP and CVP without creating the oddball delta currents that cause such issues for wildlife in the area. This would alleviate the need to cut water deliveries to Southern California.

But once you’ve got that conveyance, well, you might as well see what other water you could move with it, right? The clear prize would be the Eel River, where an enormous dam called Dos Rios was once proposed, which would have created the largest reservoir in California and sent water to the Central Valley via a tunnel. That contentious project was canceled by none other than conservative patron saint Ronald Reagan (so, if you’re keeping score, Democrat Pat Brown built the SWP, Democrat Jerry Brown is trying to build the Delta Peripheral Canal, and Republican Ronald Reagan screwed over big business in the Central Valley by canceling a dam. Just sayin’).

Again, if any sort of project were to take shape, I’d hope it could be done with much less environmental impact than Dos Rios. The Eel River flooded severely in 1964, so again, maybe a system could be set up that would only be activated during flooding events, though I don’t know how practical that would be. On the other hand, maybe you just build Dos Rios and call the lake the David Brower Reservoir, because you gotta have a sense of humor about these things.