(Originally posted on waterefficiency.net)
By Elizabeth Cutright
Editor
Water Efficiency
This week, Los Angeles, CA, mayor Antonio Villaraigosa announced that, due to concerted efforts on the part of private homeowners and government agencies, the city of Los Angeles had managed to reduce its water consumption by 17%, in July of this year. While multi-family residences measured the smallest reduction (8%), private homes achieved a 20% reduction, as government buildings dropped down a whopping 34%. Though no details were given regarding how these reductions were achieved, it’s probably safe to assume that it involved a combination of low-flow fixtures and smart irrigation techniques: basically the low-hanging fruit of water conservation. But are these small fixes enough?
For a glimpse into Los Angeles’ potential future, one need look no further than Mexico City. As a recent article in the Houston Chronicle points out, the same drought that has crippled much of Texas this year is also wreaking havoc south of the border, “killing crops and livestock and threatening to dehydrate major cities.” Mexico City in particular is struggling to keep it’s 22 million residents hydrated, and officials warn that without extreme weather intervention in the next few weeks, the city will be forced to deal with “extreme scarcity” when the dry season begins in October.
Unlike Los Angeles, which was built upon a desert, Mexico City was sits on a large lake bed that originally held more than enough water to fulfill the city’s needs. But 500 years of water waste and faulty planning have drained the lake almost entirely. And while exponential population growth is part of the problem, rampant construction—both of tunnels that flush rainfall out of the city and widespread paving of once-open land—has led to a disruption of the normal water cycle and depleted, or “over-exploited,” aquifers. And so, even though the last three months have included a fair share of rain, the area’s water basin still hold only a fraction of its normal volume—drying up while rainwater races down paved sidewalks and storm drains that empty out miles from the city center.
So, as cities like Los Angeles and Houston attempt to control and reduce water use, it will be important to look beyond showerheads and drought-resistant plants towards large-scale water resource management that includes mitigating the impact of our traditional urban landscapes on overtaxed aquifers and parched watersheds.
Monday, August 31, 2009
Monday, August 17, 2009
Thinking Big, Going Small?
(Originally posted on waterefficiency.net)
By Elizabeth Cutright
Editor
Water Efficiency
A few weeks back, a friend of mine asked my opinion on desalination, specifically a proposed desalination plant in his hometown of San Diego, CA. As he said in his message, “I am not sold on this being the answer or even one of the answers to solving southern California’s water problems.”
I responded that, at the moment, the “cons” still outweigh the “pros” when it comes to desalination as a solution for water scarcity. First off, there are the environmental factors to consider—specifically the intake apparatus (which tends to suck up innocent sea life along with gallons of salt water), and the brine discharge (which alters the salinity near the outtake valves). But just as important are the energy implications— desalination is energy-intensive, and that energy comes from fossil fuel—which means an increase of greenhouse gas emissions and, possibly, an exacerbation of current climate conditions (i.e. global warming). Finally, desalination is very expensive, especially when simple efficiency and conservation option can help you use the supply you have in a smarter, more streamlined fashion.
Of course, there’s always an exception to the rule.
A few years back, I wrote an article on the Long Beach Desalination Research and Demonstration Program, a facility designed to counteract the main drawbacks of large-scale desalination: energy consumption and environmental impact. As I stated in that article, facility opened in in September 2005 as a research and development project capable of processing 300,000 gallons of water per day. The Long Beach plant is 20–30% more energy efficient than traditional desalination; an efficiency achieved through the use of nano-filtration and specially designed filtration membranes. Additionally, development the Under Ocean Floor Seawater Intake and Discharge Demonstration System at the Long Beach facility eliminates the danger of sea life inadvertently being sucked into the pipes and killed. Finally, after water is flushed through the second set of membranes, the final output contains less than 500 milligrams of dissolved substances per liter of water, thereby complying with EPA drinking-water standards (and mitigating brine discharge).
The Long Beach project is a good example of the future of desalination—a chance to enhance our current supplies in an efficient and environmentally friendly manner. Nevertheless, developing new water supplies should be Plan B, something to fall back on once we’ve exhausted all the other options available to us. This means better leak detection, infrastructure repair and improvement, public outreach, and all other manner of water efficiency and conservation techniques we regularly discuss in Water Efficiency.
Ultimately, a cheaper—and more responsible option—would be for water-strapped communities to focus on demand reduction (via smart irrigation, low-flow fixtures, and public outreach) and increased conveyance efficiency (leak detection, infrastructure repair). Additionally, new sources in the form of water recycling (for irrigation and other non-potable uses) and rainwater harvesting should be explored before building any large, water treatment facility.
What do you think? Can our water crisis be solved by focusing on new sources (like desalination and reuse) or can small fixes (stopping that leak, convincing users to turn off that faucet) have a larger impact?
By Elizabeth Cutright
Editor
Water Efficiency
A few weeks back, a friend of mine asked my opinion on desalination, specifically a proposed desalination plant in his hometown of San Diego, CA. As he said in his message, “I am not sold on this being the answer or even one of the answers to solving southern California’s water problems.”
I responded that, at the moment, the “cons” still outweigh the “pros” when it comes to desalination as a solution for water scarcity. First off, there are the environmental factors to consider—specifically the intake apparatus (which tends to suck up innocent sea life along with gallons of salt water), and the brine discharge (which alters the salinity near the outtake valves). But just as important are the energy implications— desalination is energy-intensive, and that energy comes from fossil fuel—which means an increase of greenhouse gas emissions and, possibly, an exacerbation of current climate conditions (i.e. global warming). Finally, desalination is very expensive, especially when simple efficiency and conservation option can help you use the supply you have in a smarter, more streamlined fashion.
Of course, there’s always an exception to the rule.
A few years back, I wrote an article on the Long Beach Desalination Research and Demonstration Program, a facility designed to counteract the main drawbacks of large-scale desalination: energy consumption and environmental impact. As I stated in that article, facility opened in in September 2005 as a research and development project capable of processing 300,000 gallons of water per day. The Long Beach plant is 20–30% more energy efficient than traditional desalination; an efficiency achieved through the use of nano-filtration and specially designed filtration membranes. Additionally, development the Under Ocean Floor Seawater Intake and Discharge Demonstration System at the Long Beach facility eliminates the danger of sea life inadvertently being sucked into the pipes and killed. Finally, after water is flushed through the second set of membranes, the final output contains less than 500 milligrams of dissolved substances per liter of water, thereby complying with EPA drinking-water standards (and mitigating brine discharge).
The Long Beach project is a good example of the future of desalination—a chance to enhance our current supplies in an efficient and environmentally friendly manner. Nevertheless, developing new water supplies should be Plan B, something to fall back on once we’ve exhausted all the other options available to us. This means better leak detection, infrastructure repair and improvement, public outreach, and all other manner of water efficiency and conservation techniques we regularly discuss in Water Efficiency.
Ultimately, a cheaper—and more responsible option—would be for water-strapped communities to focus on demand reduction (via smart irrigation, low-flow fixtures, and public outreach) and increased conveyance efficiency (leak detection, infrastructure repair). Additionally, new sources in the form of water recycling (for irrigation and other non-potable uses) and rainwater harvesting should be explored before building any large, water treatment facility.
What do you think? Can our water crisis be solved by focusing on new sources (like desalination and reuse) or can small fixes (stopping that leak, convincing users to turn off that faucet) have a larger impact?
Monday, August 10, 2009
The Dead Zone
(Originally posted on waterefficiency.net)
By Elizabeth Cutright
Editor
Water Efficiency
In my July blog for Water Efficiency’s sister publication, Distributed Energy, I appropriated the age old question of a tree falling in the woods by asking “if a green building stands empty, is it still “sustainable?” After reviewing some of today’s water headlines, I’m beginning to wonder if the same holds true for conveyance systems: If new pipes are bone dry, are they still a water delivery system? Or maybe the question should be: If you build it, will the water flow?
In January, I discussed a plan put forth by the California Department of Water Resources that attempts to alleviate increasing demand in the southern portion of the state with the construction of a canal to divert water from the Sacramento River. This week, it was announced that, in fact, officials at the agency are conducting feasibility studies on an “all tunnel” option that involves a 35-mile tunnel designed to route water under the Bay Delta and deliver it to customers in the south.
Those of you following the Delta-smelt decision in California and the resulting water shortages are aware of the contentious relationship between the northern and southern parts of the state when it comes to the management of local water resources. With pumping currently restricted (because of the endangered delta smelt), there is some question as to whether a large infrastructure project such as this underground tunnel (which some opponents allege could actually stretch as far as 50 miles) can be completed in a way that protects the delicate delta ecosystem and disperses the state’s water resources in an equitable manner. Additionally, there is some concern over costs (some estimates put the bill as high as $15 billion) and how the tunnel would be managed.
On the other side of the country, a worse case scenario is already taking shape. Some of you no doubt remember Georgia Governor Sonny Purdue’s prayer for rain. Although afterwards Atlanta did experience some much-needed precipitation, it looks like the governor’s water crisis is far from over: And Georgia is not alone. In fact, the southern states are “canaries in the coal mine”: The challenges they face and the solutions they employ are part of a first front in what could be rightly called a water war.
Last month, a judge ruled that Georgia has no more than a minor legal right to the water of Lake Lanier—making Georgia the loser in a long-running water rights dispute between Georgia, Alabama, and Florida. Lake Lanier supplies three million Atlanta residents, and the loss of that resource impacts the state’s rural areas in a way that mirrors the situation in California. In fact, it’s déjà vu, with environmentalists pitted against urban residents, while farmers worry that their own water allocations will dry up. And much like the ramifications felt after the delta-smelt court decision in California severely cut back the amount of water pumped out of the delta, in June of this year, a district court ruled that without a congressional deal in the next three years, withdrawals from Lake Lanier could be drastically cut.
Of course, the main difference in Georgia is that the water from Lake Lanier belongs to three states—making a resolution that much more difficult to come by. And much like California’s governor and his water task force, Governor Purdue is weighing all his options: larger legal case based on a 150-year-old supreme court decision that gives Georgia a larger share of the lake’s water, and perhaps controversial interbasin water transfers (shifting water from one river basin to another). But even if Georgia gains rights to all the water in the lake, it won’t be enough.
That’s because a continuing drought has dried up the region’s reservoirs, including Lake Lanier. Water levels at the lake (and at the Allatoona reservoir, which also supplies water to Atlanta) have shrunk so far down that all that’s left is dirty, bacteria-laden water just inches above the “dead zone”—the final layer of stored water that’s high in organic material (like decaying plants and animals) and low on oxygen. This substandard water supplying is forcing many communities to employ ever stronger water treatment methods, proving that even if you have the infrastructure in place, in the end it’s all about the level and quality of your water supply.
Go here for more on the California water tunnel.
Go here to read about the crisis in Georgia.
By Elizabeth Cutright
Editor
Water Efficiency
In my July blog for Water Efficiency’s sister publication, Distributed Energy, I appropriated the age old question of a tree falling in the woods by asking “if a green building stands empty, is it still “sustainable?” After reviewing some of today’s water headlines, I’m beginning to wonder if the same holds true for conveyance systems: If new pipes are bone dry, are they still a water delivery system? Or maybe the question should be: If you build it, will the water flow?
In January, I discussed a plan put forth by the California Department of Water Resources that attempts to alleviate increasing demand in the southern portion of the state with the construction of a canal to divert water from the Sacramento River. This week, it was announced that, in fact, officials at the agency are conducting feasibility studies on an “all tunnel” option that involves a 35-mile tunnel designed to route water under the Bay Delta and deliver it to customers in the south.
Those of you following the Delta-smelt decision in California and the resulting water shortages are aware of the contentious relationship between the northern and southern parts of the state when it comes to the management of local water resources. With pumping currently restricted (because of the endangered delta smelt), there is some question as to whether a large infrastructure project such as this underground tunnel (which some opponents allege could actually stretch as far as 50 miles) can be completed in a way that protects the delicate delta ecosystem and disperses the state’s water resources in an equitable manner. Additionally, there is some concern over costs (some estimates put the bill as high as $15 billion) and how the tunnel would be managed.
On the other side of the country, a worse case scenario is already taking shape. Some of you no doubt remember Georgia Governor Sonny Purdue’s prayer for rain. Although afterwards Atlanta did experience some much-needed precipitation, it looks like the governor’s water crisis is far from over: And Georgia is not alone. In fact, the southern states are “canaries in the coal mine”: The challenges they face and the solutions they employ are part of a first front in what could be rightly called a water war.
Last month, a judge ruled that Georgia has no more than a minor legal right to the water of Lake Lanier—making Georgia the loser in a long-running water rights dispute between Georgia, Alabama, and Florida. Lake Lanier supplies three million Atlanta residents, and the loss of that resource impacts the state’s rural areas in a way that mirrors the situation in California. In fact, it’s déjà vu, with environmentalists pitted against urban residents, while farmers worry that their own water allocations will dry up. And much like the ramifications felt after the delta-smelt court decision in California severely cut back the amount of water pumped out of the delta, in June of this year, a district court ruled that without a congressional deal in the next three years, withdrawals from Lake Lanier could be drastically cut.
Of course, the main difference in Georgia is that the water from Lake Lanier belongs to three states—making a resolution that much more difficult to come by. And much like California’s governor and his water task force, Governor Purdue is weighing all his options: larger legal case based on a 150-year-old supreme court decision that gives Georgia a larger share of the lake’s water, and perhaps controversial interbasin water transfers (shifting water from one river basin to another). But even if Georgia gains rights to all the water in the lake, it won’t be enough.
That’s because a continuing drought has dried up the region’s reservoirs, including Lake Lanier. Water levels at the lake (and at the Allatoona reservoir, which also supplies water to Atlanta) have shrunk so far down that all that’s left is dirty, bacteria-laden water just inches above the “dead zone”—the final layer of stored water that’s high in organic material (like decaying plants and animals) and low on oxygen. This substandard water supplying is forcing many communities to employ ever stronger water treatment methods, proving that even if you have the infrastructure in place, in the end it’s all about the level and quality of your water supply.
Go here for more on the California water tunnel.
Go here to read about the crisis in Georgia.
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