Delta blues: A modeling effort suggests that as sea levels rise, it won’t be cost effective to save some tracts of low-lying land in California’s Sacramento Delta, shown here.
Public Policy Institute of California
Amid rising seas, a California modeling effort recommends abandoning land tracts in the Sacramento Delta.
A new multidisciplinary modeling effort concludes that certain tracts of land in California's Sacramento Delta should be abandoned the next time they flood, and that major California water-supply inlets in the area should be rerouted. The study indicates the kind of land-preservation and infrastructure triage that will become increasingly necessary in the face of rising sea levels and climate change.
"It's always difficult and controversial to look at these kinds of things," says Jay Lund, a professor of environmental engineering at the University of California, Davis, who co-led the study. "For those delta landowners where the policy has been historically to help them--they would be losers. But I don't see any way they are not going to be losers, so the state policy should be that we all quit losing." This week, Lund spoke about the study at a California Energy Commission conference on climate-change research, held in Sacramento.
The Sacramento Delta is where the Sacramento and San Joaquin rivers converge with each other and meet incoming salt water from the San Francisco Bay. The area is a source of fresh water for agribusiness and more than 20 million Californians. Within the delta, tracts of land have been reclaimed over the past century, mostly for farming. Earthen levees--which, if put end to end, would stretch more than 1,000 miles--keep water-supply inlets fresh and reclaimed areas dry.
But a combination of settling land, rising sea levels, and the prospect of levee destruction from earthquakes have long threatened the area. In 2004, when a delta levee unexpectedly collapsed, the state and federal governments rushed in to repair it, spending more than $75 million. However, the effort protected land worth only $22 million. "Throwing a lot of money at a low-value private asset is not something you want to do with taxpayer money very often," says Richard Howitt, an economist at UC Davis who participated in the study. "We wanted to put a lot of work into what really amounts to a triage list--and say which islands, if they collapse, we say, 'Sorry about that,' but you don't repair them or pump them. You adjust to a new ecology." (By "islands," Howitt means low-lying tracts protected from surrounding water by levees.)
The study--which spanned disciplines including civil engineering, climate science, economics, hydrology, and biology--specifies a precise boundary between areas that should and shouldn't be saved. It also recommends that long-considered plans to build a canal to divert water supplies from points upstream on the two rivers should be carried out now; the present inlet points cannot be protected from salt-water incursion in the long term. The canal proposal was defeated in a 1982 referendum, but ultimately, Lund says, some environmental concerns about the canal's construction will be moot, because unstoppable salt-water incursions will reshape the area's ecology. Indeed, the study notes that its recommendations for the delta are "one example of how climate-change will shake-up long-cherished notions of environmental management and sustainability."
"Unless we get some serious modeling," Lund adds, "we're never going to get ahead of these changes. We're just going to be reactive."
Research may be needed to evaluate alternatives to reducing greenhouse-gas emissions.
The London Olympics' site reflects a trend toward urban planning that contemplates climate resiliency and reduced emissions.
While rising sea levels have yet to be documented, it's certainly good to be thinking about these things. Coping with climate change, manmade or not, is a much better strategy than trying to alter it.
I trust none of it.
Dollar-value is not a reliable metric. This article asserts that the levee repair cost was 75 million dollars to protect land "worth" 22 million dollars. The methodology used for determining the "value" of land expressed in dollars is going to be flawed because the "value" of land in dollars varies. For example, when dollars are the metric, prime agricultural land is of lower "value" than land zoned for houses or Walmarts. Acreage covered with government offices is of a higher dollar value than acreage producing wheat, rice, tomatoes, celery, onions or cattle. The Delta land in this article is probably the finest farmland in California which means it equals or surpasses the finest farmland in the nation. Levees can be rebuilt, ag land cannot.
Money and politics trump science. That's the way it is in California.
Economic forces dominate Sacramento. Over-development south of the Tehachapi mountains from Los Angeles County to San Diego County is an under-reported disaster. Thus, the objectivity of the University report is shadowed by money and politics and the need in this faltering economy for large public works projects.The Governor, Westlands Water District and Metropolitan Water of Los Angeles want a peripheral canal in the Delta, they are pushing for it with an ongoing propaganda campaign which one hears every day on the major AM radio stations out of San Francisco.
The Pacific salmon runs are failing, the Delta Smelt are nearly extinct, but this is a water war. The southern half of the state wants the northern half's water and will destroy the Delta and its habitat to get it. Studies which support that destruction must be considered suspect.
Re: More than Nature is at work.
suppose you tripple the value of the land and you'll have something like $75 million of public money spent to protect $66 million in private property.
An alternative is for the localities to decide how much they tax them selfs to prepare for disasters ware a levee breaks. Each levee protects certain tracks of land and land owners pay for the maintenance of those levees. If the land isn't of enough value then the land owners would decide that the levee isn't worth protecting.
Part of my family is from the delta area. I remember in the fifties when all of the homes in the delta area were built up on 5 ft. high stilts. I asked my uncle why this was so, and he said that it was for the yearly floods.
What we seem to be missing here is the fact that all of the work to harness hydroelectricity, store water, and feed development resulted in the constant damming of the river systems mentioned in this article. Those rivers revived and replenished the siltation of the delta region, provided access for spawning grounds that fed the the salmon and smelt runs. All is gone for the sake of controlling what nature did to replenish and sustain the delta. No more silt means no more build up of the delta. No more spawning grounds means no more fish! Fish ladders don't remake flooded spawning grounds behind the dams.
The old saying amongs family members was that as kids, they could cross the Sacramento on the backs of salmon. Today, amongs those still alive, they are sorry that they helped to build some of the dams that choke the rivers today!
Just another man made disaster..........
Soarhead
Focus, not on CO2, but on the 10 billion pounds of aerosol (non-CO2) pollutants drifting over North America every year from East Asia. Those pollutants wash out into the mountains, forests, lakes, streams, and coastal waters. The Sacramento Delta is very susceptible to such pollution. We should be making trade policy partly dependent upon environmental cleanup from our upwind trade partners.
Manufacturing in the United States is in trouble. That's bad news not just for the country's economy but for the future of innovation.
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pritchet1
1 Comment
Strategy for Coping with Climate Change?
Sounds like another "Do Nothing" strategy. Look to the Dutch. They have been working on solutions for hundreds of years and pushed the sea back.
Or make the area more "productive" by providing oil refineries there. It worked for the delta around New Orleans!
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bugme
29 Comments
Re: Strategy for Coping with Climate Change?
Did anyone talk to the Department of Water Resources? or just read the Department of Energy's report? DWR may have a plan in the works.
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andy_mydur
6 Comments
Re: Strategy for Coping with Climate Change?
IPCC report 4 is a pre-emptive measure for the globe to act in consensus among scientists to warm up against the issues viz .Sea rise ,glacier melting in himalayas which can threaten human living and possible threat for extinction of plants & animals ,which is evident in forests & oceans .
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