On earth, groundwater is ubiquitous and like all water on earth it comes from precipitation that percolates through the soil until it reaches the zone of saturation. Though groundwater is everywhere the quantity and usability of groundwater varies from location to location based on geology and precipitation. The rate at which precipitation percolates through the soil to resupply the groundwater is called the recharge rate and also varies for site to site. Groundwater is water that fills the cracks and pores of rocks and sediments that lie beneath the surface of the earth saturating those materials. Gravel, sand, sandstone, or fractured rock have large connected spaces that allows water to flow through them allowing an aquifer to form. Impervious layers of clay and bedrock prevent ground water moving from one space to another. Rain and snow pass through the soils, rocks and sediments to constantly make more ground water. In order for the water supply to be sustainable, groundwater cannot be withdrawn faster than it is resupplied.
Due to its protected location underground, most groundwater is naturally clean and free from pollution. Not understanding the nature of groundwater and the important role it plays in sustaining life, we have over used it and abused it. In the past when we buried fuel tanks, industrial and household waste at landfills, poured solvents out into the dirt, used excessive amounts of fertilizer, had uncontrolled waste from animal feedlots we were contributing to the contamination of groundwater. Homeowner disposal of chemicals, treating a home for termites, excessive use of fertilizers (even organic), and malfunctioning septic systems can all impact onsite groundwater quality and potentially down gradient sites.
In addition to contamination we can damage groundwater supplies by pumping groundwater beyond its recharge rate literally using up this valuable resource. Fresh, potable, uncontaminated water is not unlimited. According to the Stockholm International Water Institute, about a fifth of water used globally is groundwater and that portion is growing. California has for several generations been a leader in water management, moving water from where the rain and snow falls to where the water is needed in what was hoped to be a reliable and sustainable way. Water banking is used within the state to reallocate water from lower use areas to recharge the aquifer in high demand areas. Through tight management techniques, California was until recently able to supply the state with water in a sustainable way. Periodic droughts have historically plagued the system, now though, less than average rainfall for more than one year seems to be all it takes to upset the cart.
Recent advances have made it possible to measure groundwater supplies using satellites. The orbiting satellites measure the gravitational pull of water below the earth’s surface and now are able to confirm that the groundwater level is falling in areas of India. Over the years the water table has fallen in California. While irrigation has allowed the world’s farmers to produce vastly increased amounts of wheat, rice and other staples. The demands of mankind for water to sustain life and to produce food have continued to grow with growing population. Internationally, both groundwater and surface water supplies are strained. In India the monsoon rains have been the weakest in five years and that is exacerbating demand for groundwater based irrigation. The India’s Central Ground Water Authority regulates the pumping from aquifers. Unsustainable pumping in some areas has resulted in a drop in the water table and sea water intrusion. Groundwater aquifers cross international borders and water rights and potable water supplies will become the crisis of the twenty first century.
Showing posts with label Water in California. Show all posts
Showing posts with label Water in California. Show all posts
Thursday, August 20, 2009
Monday, August 17, 2009
California's Water Supply at the Breaking Point
As pointed out in the WSJ Opinion piece by Rep. Nunes California has the largest water storage and transportation system in the world. With 1,200 miles of canals and nearly 50 reservoirs, the system captures enough water to irrigate about four million acres and provide water to 23 million people. In many cases, water in this system is sold to communities by the federal government. The price for this water is not based on it’s value or scarcity, but on an arbitrary rate. Limited resources are allocated by the government. Without this extensive management system California’s limited water resources could not supply the state. California has for several generations moved the water from where the rain and snow falls to where the water is needed in what was hoped to be a reliable and sustainable way.
Ground water supplies which typically supply 40% of the state’s needs in an average year are carefully managed in the public supply wells so that the amount of water pumped out does not exceed the amount recharged over time. Water banking is used to reallocate water from lower use areas to recharge the aquifer in high demand areas. Much of the usable water in the state falls as rain and snow in the northern third of the state during the winter on the western slope of the Sierra Nevada Mountains. The cities of California and the irrigation demands of the San Joaquin Valley have grown to demand more than three quarters of the water available in the state. As population has grown California has developed the most complex water storage, transport and flood management system found anywhere in the world.
The Central Valley Project began in the 1930’s and was completed with the State Water Project in 1970’s. While these projects were considered engineering marvels at the time and have provided the fluid of life to the state’s economic growth, they were not built to meet all the demand placed on them today. Nor were they built with the Sacramento and San Joaquin River Delta’s current environmental issues in mind. To a large extent those environmental problems have been caused by water diversions, invasive species and loss of habitat to development. We seem to have reached the breaking point for the state despite the fact that California reservoirs have received 80% of their normal amount of water and precipitation in the northern Sierras has been 95% of its yearly average this year.
According to Rep. Nunes, sections of the San Joaquin Valley is being transformed into a dust bowl. Thousands of acres lay fallow, while almond, olive, plum trees and grape vines are being left to die in the sun. Tens of thousands of people have lost their jobs because of the depression level drought in some sections of the Central Valley. This is a regulatory-mandated drought. Almost all water in California is delivered so where to deliver it, is a choice of the state water agencies. The needs of California have been increased. The 1973 Endangered Species Act requires that the government take steps to save endangered species. In California, that's meant diverting vast sums of water into rivers and streams to prevent salt water intrusion, protect fish while allowing the farms without private goundwater supplies to go dry. The limitation of the water supply these past couple of years have forced federal authorities to decide who to serve, fish or farmers. In California, there isn't enough money or water to go around this year,. The federal government has plans to divert more water into the Delta and the San Francisco Bay. California is sending out glossy brochures about the water supply with directions and encouragement to conserve water.
There simply is no longer enough water. Trees are being stumped in hopes of saving orchards. Individual farmers are pumping what groundwater they have beyond the recharge rate to save their investment in trees and vines or just survive. The state can not easily prevent this pumping. The NY Times reported that due to the increasing drought in California farmers have been pumping more groundwater to irrigate their crops, lowering the level of the groundwater. As a result the state has begun to try and collect data on groundwater supplies with an eye to regulation. Water is not sold at market prices. In most communities water is still less than a penny per gallon at the tap. Encouraging individuals to conserve is a viable method of reducing demand. Raising the price of water might encourage this behavior. Food prices do not reflect the water subsidy, and the environment is not paying for the water.
The economy of California based on control of the water and the allocation is based on regulatory decisions. The water supply has failed to match the demand for a product with no real price, and the economy of the state has also failed. The demand for and use of water must be reduced or the supply increased. I leave it to you to determine the best way to do that. Reduce the acreage of cultivated land? Reduce the population? Ration water to all citizens? Reduce the resources to maintain the environment? Or will the state find the resources to build desalination plants? Whatever solution California chooses, will be a game changer for California and the American economy. The people of the state will be poorer because resources will now be diverted to provide more water or less water will be available for agriculture. America will be poorer, California represents 20% of the US economy.
Ground water supplies which typically supply 40% of the state’s needs in an average year are carefully managed in the public supply wells so that the amount of water pumped out does not exceed the amount recharged over time. Water banking is used to reallocate water from lower use areas to recharge the aquifer in high demand areas. Much of the usable water in the state falls as rain and snow in the northern third of the state during the winter on the western slope of the Sierra Nevada Mountains. The cities of California and the irrigation demands of the San Joaquin Valley have grown to demand more than three quarters of the water available in the state. As population has grown California has developed the most complex water storage, transport and flood management system found anywhere in the world.
The Central Valley Project began in the 1930’s and was completed with the State Water Project in 1970’s. While these projects were considered engineering marvels at the time and have provided the fluid of life to the state’s economic growth, they were not built to meet all the demand placed on them today. Nor were they built with the Sacramento and San Joaquin River Delta’s current environmental issues in mind. To a large extent those environmental problems have been caused by water diversions, invasive species and loss of habitat to development. We seem to have reached the breaking point for the state despite the fact that California reservoirs have received 80% of their normal amount of water and precipitation in the northern Sierras has been 95% of its yearly average this year.
According to Rep. Nunes, sections of the San Joaquin Valley is being transformed into a dust bowl. Thousands of acres lay fallow, while almond, olive, plum trees and grape vines are being left to die in the sun. Tens of thousands of people have lost their jobs because of the depression level drought in some sections of the Central Valley. This is a regulatory-mandated drought. Almost all water in California is delivered so where to deliver it, is a choice of the state water agencies. The needs of California have been increased. The 1973 Endangered Species Act requires that the government take steps to save endangered species. In California, that's meant diverting vast sums of water into rivers and streams to prevent salt water intrusion, protect fish while allowing the farms without private goundwater supplies to go dry. The limitation of the water supply these past couple of years have forced federal authorities to decide who to serve, fish or farmers. In California, there isn't enough money or water to go around this year,. The federal government has plans to divert more water into the Delta and the San Francisco Bay. California is sending out glossy brochures about the water supply with directions and encouragement to conserve water.
There simply is no longer enough water. Trees are being stumped in hopes of saving orchards. Individual farmers are pumping what groundwater they have beyond the recharge rate to save their investment in trees and vines or just survive. The state can not easily prevent this pumping. The NY Times reported that due to the increasing drought in California farmers have been pumping more groundwater to irrigate their crops, lowering the level of the groundwater. As a result the state has begun to try and collect data on groundwater supplies with an eye to regulation. Water is not sold at market prices. In most communities water is still less than a penny per gallon at the tap. Encouraging individuals to conserve is a viable method of reducing demand. Raising the price of water might encourage this behavior. Food prices do not reflect the water subsidy, and the environment is not paying for the water.
The economy of California based on control of the water and the allocation is based on regulatory decisions. The water supply has failed to match the demand for a product with no real price, and the economy of the state has also failed. The demand for and use of water must be reduced or the supply increased. I leave it to you to determine the best way to do that. Reduce the acreage of cultivated land? Reduce the population? Ration water to all citizens? Reduce the resources to maintain the environment? Or will the state find the resources to build desalination plants? Whatever solution California chooses, will be a game changer for California and the American economy. The people of the state will be poorer because resources will now be diverted to provide more water or less water will be available for agriculture. America will be poorer, California represents 20% of the US economy.
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