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power-water nexus

Power to the Utilities?

December 13, 2013
communciations, Education, engineering, finance, funding, Holistic Water Planning, infrastructure, innovation, Leadership, local government, management, Marketing water, planning, power demands, power-water nexus, renewable power, solar power, utilities, Water Funding, water sewer management, wind power
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Local utilities are among the largest power users in their communities.  This is why power companies make agreements with utilities at reduced cost if the utilities will install backup power supplies.  The peak power generation capacity as well as backup capacity is at the local utilities and other large users.  Power companies can delegate this capital cost to large users without the investment concerns.  It works for both parties.  In addition, power companies spend effort to be more efficient with current power supplies, because recovering the costs for new, large plants is difficult, and in ways, cost prohibitive.  Hence small increment options are attractive, especially when they are within high demand areas (distributed power).  The use of localized wind, solar and on-site energy options like biogas are cost effective investments if sites can be found.  That is where the utilities come in.  Many utilities have sites.  Large water utilities may have large reservoirs and tank sites that might be conducive to wind or solar arrays.  Wind potential exists where there are thermal gradients or topography like mountains.  Plant sites with many buildings and impervious areas could also be candidates for solar arrays and mini-wind turbines.  Wastewater plants are gold mines for digester gas that is usually of high enough quantity to drive turbines directly.  So utilities offer potential to increase distributed power supplies, but many water/wastewater utilities lack the expertise to develop and maintain these new options, and the greatest benefit is really to power companies that may be willing to provide as much money in “rent” to the utilities as they can save.   Power entities obviously have the expertise and embedded experience to run distributed options optimally.  So why don’t we do this?

I would speculate several reasons.  First, the water/wastewater utilities have not really considered the option, and if they do there is the fear of having other folks on secure treatment sites.  That can be overcome.  The power entities have not really looked at this either.  The focus in the power industry is to move from oil-based fuels to natural gas to accumulate carbon credit futures, the potential for lower operating costs and better efficiency of current facilities to reduce the need for capital investments.  Power entities operate in a tight margin just like water/wastewater utilities do so saving where you can is a benefit.  There are limited dollars to invest on both sectors and political and/or public service commission issues to overcome to invest in distributed power options at water/wastewater facilities. 

But a longer-term view is needed.  While fossil fuels have worked for us for the last 100 years, the supply is finite.  We are finding that all that fracking might not give us 200 years, but more like 20-40 years of fuel.  We have not solved the vehicle fuel issue and fossil fuels appear to be the best solution for vehicles for the foreseeable future which means they will compete directly with power demands.  Natural gas can be used for vehicles fairly easily as evidenced by the many transit and local government fleets that have already converted to CNG. 

The long-term future demands a more sustainable green power solution.  We can get to full renewable power in the next 100 years, but the low hanging fruit need to be implemented early on so that the optimization of the equipment and figuring out the variables that impact efficiency can be better understood than they are now.  For example, Leadville, CO has a solar array, but the foot of snow that was on it last September didn’t allow it to work very well.  And solar arrays do use water to clean the panels.  Dirty panels are nowhere near as efficient as clean ones.  We need to understand these variables.

Area that are self sufficient with respect to power will benefit as the 21st century moves forward.  There are opportunities that have largely been ignored with respect to renewable power at water and wastewater facilities, and with wastewater plants there is a renewable fuel that is created constantly.  Wastewater plants are also perfect places to receive sludge, grease, septage, etc which increase the gas productions.  There are examples of this concept at work, but so far the effort is generally led by the wastewater utilities.  An example is East Bay Municipal Utility District (Oakland, CA) which produces 120% of its power needs at its wastewater plant, so sells the excess power back to the power company.  There are many large wastewater plants that use digester gas to create power on-site to heat digesters or operate equipment.  Others burn sludge in on-site incinerators to produce power.  But so far the utilities are only reducing their cost as opposed to increasing total renewable power supplies.  A project is needed to understand the dynamics further.  If you are interested, email me as I have several parties wishing to participate in such a venture. 

SRF Wars in Congress – What it Means to Utilities

December 9, 2013
communciations, Congress, economy, Education, engineering, finance, Holistic Water Planning, infrastructure, innovation, Leadership, local government, management, Marketing water, planning, power-water nexus, Revenues, utilities, Water Funding, water sewer management
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As 2014 is only a month away, expect water and sewer infrastructure to become a major issue in Congress.  While Congress has failed to pass budgets on-time for many years, already there are discussions about the fate of federal share of SRF funds.  The President has recommended reduction in SRF funds of $472 million, although there is discussion of an infrastructure fund, while the House has recommended a 70% cut to the SRF program.  Clearly the House sees infrastructure funding as either unimportant (unlikely) or a local issue (more likely).  Past budgets have allocated over $1.4 billion, while the states put up a 20% match to the federal share.  A large cut in federal funds will reverberate through to local utilities, because many small and medium size utilities depend on SRF programs because they lack access to the bond market.  In addition, a delay in the budget passage due to Congressional wrangling affects the timing of SRF funds for states and utilities, potentially delaying infrastructure investments. 

This decrease in funding comes at a time when ASCE rates water and wastewater system condition as a D+ and estimates over $3 trillion in infrastructure investment will be needed by 2020.  USEPA notes that the condition of water and wastewater systems have reached a rehabilitation and replacement stage and that infrastructure funding for water and sewer should be increased by over $500 billion per year versus a decrease of similar amounts or more.  Case Equipment and author Dan McNichol have created a program titled “Dire Straits:  the Drive to Revive America’s Ailing Infrastructure” to educate local officials and the public about the issue with deteriorating infrastructure.  Keep in mind much of what has made the US a major economic force in the middle 20th century is the same infrastructure we are using today. Clearly there is technical momentum to indicate there is greater need to invest in infrastructure while the politicians move the other way.  The public, caught in the middle, hears the two sides and prefers less to pay on their bills, so sides with the politicians as opposed to the data. 

Local utilities need to join the fray as their ability to continue to provide high quality service.  We need to educate our customers on the condition of infrastructure serving them.  For example, the water main in front of my house is a 50 year old asbestos concrete pipe that has broken twice in the past 18 months. The neighborhood has suffered 5 of these breaks in the past 2 months, and the City Commission has delayed replacement of these lines for the last three years fearing reprisals from the public.  Oh and the road in front of my house is caving in next to where the leak was.  But little “marketing” by the City has occurred to show the public the problem.  It is no surprise then that the public does not recognize the concern until service is interrupted.  So far no plans to reinitiate the replacement in front of my house.  The Commission is too worried about rates.

Water and sewer utilities have been run like a business in most local governments for years  They are set up as enterprise funds and people pay for what they use.  Just like the private sector.  Where the process breaks down is when the price is limited while needs and expenses rise.  Utilities are relatively fixed in their operating costs and I have yet to find a utility with a host of excess: workers.  They simply do not operate in this manner.  Utilities need to engage the public in the infrastructure condition discourse, show them the problems, identify the funding needs, and gain public support to operate as any enterprise would – cover your costs and insure you keep the equipment (and pipes) maintained, replacing them when they are worn out.  Public health and our local economies depend on our service. Keep in mind this may become critical quickly given the House commentary.  For years the federal and state governments have suggested future funding may not be forthcoming at some point and that all infrastructure funding should be local.  That will be a major increase in local budgets, so if we are to raise the funds, we need to solicit ratepayer support.  Now!  

RENEWABLE POWER VS THE ESTABLISHMENT (How water and sewer utilities play a part)

September 24, 2013
Climate, economy, engineering, Environment, finance, hydroelectric power, infrastructure, innovation, power demands, power-water nexus, renewable power, solar power, Uncategorized, water sewer management, wind power
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In June, President Obama made a speech about the increase in renewable power that the United States had created in the last 4 years, and announced goals to double this amount in the next four.  Virtually all of this power was solar and wind power.  Little mention was made of hydroelectric or onsite sources.  But the latter have been around much longer than the former sources and there may be options to increase their contributions under the right circumstances. 

 

Hydroelectric power has been in use in the US for over 100 years.  By the 1930s, 40 percent of the nation’s power came from hydroelectric dams, including some fantastic accomplishments of the time like the Hoover Dam.  Today we have over 100,000 dams in the US, most of which provide power.  Today hydroelectric is only 6 percent of our total.   The reluctance to continue with hydroelectric power involved fisheries, land acquisition costs and legal issues.  Some hydropower options are excellent.  Hurting fisheries (which disrupt local economies dependent on those fisheries) may not be, and therein lies part of the dilemma.

 

But water and wastewater utilities are actively looking for means to reduce power costs.  Depending on the utility, pumping water can account for 80-90 percent of total power consumption, especially with high service pumps on water systems that require high pressures.  More efficient pumps is one obvious answer, but of fairly limited use unless your pumps are really old.  Variable speed drives can increase efficiency, and the cost is dropping.  But note that with all that high pressure, how do utilities recapture the energy?  We often don’t and the question is whether there is a means to do so that can benefit up.  The first step is looking at plant hydraulics.  Is there a way to recapture energy in the form a pressure.  For example of reverse osmosis systems, we can install a turbine to recapture the pressure on the concentrate side.  They are not very efficient at present, but the potential is there.  On long gravity pipe runs for water supply, a means to recapture pressure might also be available. 

 

Of course on-site generation of power is a potential solution. Water and sewer utilities have land, and on the wastewater side, methane, so producing power is possible.  This solution, however, may not be embraced by power utilities due to the potential revenue reduction potential and loss of embedded reserve capacity at water and wastewater plants.  As the water facility takes on on-site generation, their load profile may shift significantly placing them in under a different rate structure. This may greatly reduce the benefit to the facility.  There are, however, approaches to permit win-win solutions. The goal is to put willing power and water utilities together to permit local generation that will benefit both power and water utility systems to encourage public – private partnerships.  A medium to large wastewater plant can generate at least a third of its power needs.  Some even more if they take in grease, oils and other substances that should not be put into the sewer system.  The potential there is significant.  EBMUD has a plant that is a net seller of power.  We should look for opportunities.  But don’t forget, water utilities can create hydropower without impacting fish populations. We just need to seek out the right opportunities.

OnSIte Power At Utility Plants?

March 6, 2013
Climate, Leadership, planning, power demands, power-water nexus, sustainability, Uncategorized
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Since Richard Nixon was President, the federal government has been talking about reducing our reliance of foreign oil.  Since 2008, our dependence has dropped from 57 to 42 percent.  The foreign oil has been replaced by domestic oil and gas, conversion of power plants to natural gas, and investments in renewable power like wind (4% US production and) and solar power.  Coal has remained a constant, although future regulations of coal plant emission may alter this.  Federal loans from DOE have included $13 billion for solar energy, 1.7 billion for wind and 10 billion for nuclear power.  All other renewables account for 1.2 billion.  Power companies have invested in the renewable technologies in part because of low loan rates from the federal government, and partly due to tax credits (2.2 cents/kW-hr), but power entities like NextEra Energy have made cleaner power a basis of their future.  So what does this have to do with water utilities?  First, water and wastewater plant are often the largest users on the power grind in communities.  This is why they are able to get load control agreements.  The peak demands are the load control agreements, which means power providers can construct fewer plants, and keep rates down.  At the same time water and wastewater utilities benefit fro reduced rates, but have construct backup systems (which are needed if the power grid fails anyway.  Benefit to both parties.  But as the demands for power on the grid increase, and as regional demands in areas that are substantially constructed already, locating new power is difficult.  Transmission losses are 6 or more percent, and involve complicated federal FERC regulations.  So the SMART grid issue is distributed power, and finding sites for distributed power might be tough.  Or maybe not.  Water and wastewater plants have land, so there is an obvious fit.  But the rub is that if the water and wastewater people own the facilities, it decreases the peak capacity, meaning the power entities must build more capacity.  So perhaps there is a means to get revenues (leases) to water folks, while helping the smart grid.  I am thinking about developing a project proposal for this.  Let me know if you are interested.  Meanwhile if you have a success story, I’d love to hear it.

Planning the Future or Not?

March 2, 2013
Climate, communciations, finance, funding, groundwater, infrastructure, Leadership, management, planning, power demands, power-water nexus, sustainability, Uncategorized
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Many of you will remember in the 1980s there was a book called Megatrends by John Naisbett, and a later update called Megatrends 2000 and a host of other megatrend documents.  The concept was to look for global or national trends that might impact out future.  I recalled this while I was reading an article from Forbes and Public Works magazines recently talking about the future, and development of megaregions.  They project 11 megaregions in the US that will develop by 2050.  Most are in process already and are familiar:  1) Pacific Northwest (Vancouver to Portland), 2) Bay Delta, 3) Southern California, 4) Front range (Cheyenne to Albuquerque, 5) Phoenix/Tucson, 6) Texas Triangle (Houston-Dallas-San Antonio, 7)  Gulf Coast (Houston to Mobile), 8)  Florida (I-4/I95), 9)  Piedmont (Atlanta to Raleigh), 10)  Northeast (Washington DC to Boston), and 11) southern Great Lakes (the old “Rust Belt”).  If you are looking for economic growth, all signs point to these 11 region.  Most are located along interstates which makes transportation by truck easier.  Several have port access and most rail.  The projection is for more people to move from the rural areas to these regions, and for the influx of immigrants to likewise migrate here.  But an issue not noted as a part of these projection is that only three of them are not water limited, and those three include the two oldest regions:  Rust Belt stats and the northeast where there is water.  In addition, three of these areas are characterized by potential adverse climate impacts (Pacific Northwest, Texas, and Front Range) that will adversely impact their future water availability.  In all but the historical cases, embedded power availability is lacking, creating competing interests with the water industry.  So where is the planning and forecasting models for 2050 and beyond for these regions?  Some jurisdictions have seen attacks on traditional planning activities as unduly limiting development, implement specific agendas, and other nefarious reasons.  Florida scrapped most of its growth management/concurrency requirements in this vein.  After all, why should you insure there is water in order to issue development permits right?  That might limit development! Why not manage an aquifer for 100 years, to insure a 100 year supply, not to insure the supply remains available indefinitely.  Both short term goals conflict with the theory of constraints which says that any system is limited in achieving its goals by a very small number of constraints; kinda the old idiom “a chain is no stronger than its weakest link.”  The concept requires the application and investigation of the situation in enough detail to gain an understanding of the constraints and to construct an optimized solution.  Keep in mind that often maximizing certain goals, will cause others to suffer.  A familiar example, you can have construction occur fast and with high value, but not at a low price.  You can achieve certain reliability of water supplies, and improve economics, but you need to understand other impacts.  Too often planners focus on meeting the goals of the client, while ignoring competing goals, which ultimately leads to greater costs down the line.  As these megaregions are well on their way to development, we need to begin the process (a bit late, but better late than never) to understand the limitations each region will face with respect to water supplies and how those water supplies impact competing economies.  Failure to do so could create constraints within the regions that restrict their growth and economic potential.

Optimizing Water Supplies in the Face of Climate, Economic and Population Demands

February 26, 2013
Climate, Environment, infrastructure, Leadership, management, power demands, power-water nexus, sustainability, Uncategorized, water supplies
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The world population is expected to grow to over 9 billion by 2050, an exponential trend that has continued for several hundred years and see no end it site.  Megaregions as people flock to cities and industry will be commonplace.  The question is how will water supplies be impacted, or impact this trend.  Interestingly it varies everywhere.  For example, China and India are not expected to reap major benefits from climate changes, so their economies will grow as will populations.  They continue to construct coal fired power plants, and impact carbon dioxide and pollution levels, which does not help the climate issues.   Recall that Beijing was basically shut down for several days recent due to smog – seems like I recall the first air pollution regulations stemming from Henry the VIII decision to move the coal plants out of London during his reign 500 years ago because of pollution, but perhaps we need to relearn history J.  Of course China and India are expected to be less affected than the more historically developed countries in the northern latitudes that have been moving to renewable and less impactful power solutions with good reason.  Aside from these two economies, the rest of the northern latitudes are likely to see changes in temperature, variation in precipitation patterns and drought frequency changes.  That has major impacts for a billion people who will see water supply shortages occur much more often, and create a whole host of “winners” and “losers” in the water supply category.  Conflicts may result from the need to change increase water supplies as desperation kicks in.  Lawrence Smith, in his book 2050, suggests that while the far northern countries, the US, Russia, the Scandanavian countries, and Canada may see more land for agriculture and more water (at least in some areas), those warmer countries in the sub-Sahara, will become more desperate and dangerous to the world order.  Water will be the new oil, and the tipping point for sustainability, akin to peak oil, needs to be developed.  The cost will be significant, but the failure will be catastrophic to global economies.  This is part of why the global pursuit of renewable power, local solutions and green jobs.  It is why the definition of sustainable water supplies continues to evolve as we understand that the impacts, or the constraints of water supplies is far more reaching than most engineers and planners have traditionally dealt with.  AWWA published a Sustainable Water CD several years ago.  It was a series of papers of different aspects of sustainability as applied to water resources.  The last paper summarized the findings and compared it to the initial paper discussion.  The conclusion was the concept is evolving.  Climate, power, agriculture, natural systems, local economies, local economic contributions to regional and national economies and politics all impact pure science recommendations for water supply allocation.  The question is can we overcome the politics to create a optimized science solution to sustain water supplies and economies.  An old Native American proverb comes to mind:  We do not inherit the Earth from our grandparents, we borrow it from our grandchildren.

Sea Level Rise may Impact low lying areas faster than we think

February 23, 2013
Climate, communciations, Environment, groundwater, infrastructure, Leadership, Marketing water, planning, power demands, power-water nexus, sanitary sewer, sea level rise, stormwater, sustainability, Tidal flooding, Uncategorized, water sewer management
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One of the major issues involved with climate changes is sea level rise. Florida has experienced 9 inches of sea level rise since 1900. Projections are 2-3 feet by 2100, perhaps more. Modeling done by my students and I at FAU has demonstrated that in low lying areas, sea level rise will also impact groundwater levels, and accelerate inland flooding. The graphs above compare the traditional bathtub model used by most investigators and our adjusted for groundwater level model. You wee added inland areas of flooding which complicated storm water flooding issues much faster than sea level rise might indicate.

Leadership with Water-Energy Nexus?

January 26, 2013
Climate, communciations, Environment, finance, groundwater, infiltration, infrastructure, Leadership, management, power demands, power-water nexus, sanitary sewer, sustainability, water sewer management, water supplies
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In our prior blog discussions the theme has been leadership.  Vision is needed from leaders.  In the water industry that vision has to do with sustainability in light of competing interests for water supplies, completion for funds, maintaining infrastructure and communicating the importance of water to customers.  The need to fully to optimize management of water resources has been identified.  The argument goes like this.  Changes to the terrestrial surface decrease available recharge to groundwater and increase runoff.  Urbanization increases runoff due to imperviousness from buildings, parking lots, and roads and highways that replace forest or grassland cover, leading to runoff at a faster rate (flooding) and the inability to capture the water as easily.  In rural areas, increased evapotranspiration (ET) is observed in areas with large-scale irrigation, which lowers runoff and alters regional precipitation patterns. At the same time there are four competing sectors for water:  agriculture (40% in the US), power (39% in the US), urban uses (12.7%) and other.  Note the ecosystem is not considered.

New water supplies often have lesser quality than existing supplies, simply because users try to pick the best water that minimizes treatment requirements. But where water supplies and/or water quality is limited, energy demands rise, often to treat that water as well as serve new customers. For many non-industrial communities, the local water and wastewater treatment facilities are among the largest power users in a community.  Confounding the situation is trying to site communities where there is not water because the power industry needs water and the residents will need water.  It is a viscous cycle.  When you have limited water supplies, that means your development should be limited.  Your population and commercial growth cannot exceed the carrying capacity of the water supply, or eventually, you will run out.  Drawing water from more distant place can work for a time, but what is the long-term impact.  Remember the Colorado River no longer meets the ocean.  Likewise the Rio Grande is a trickle when it hits the Gulf of Mexico  As engineers, we can be pretty creative in coming up with ways to transfer water, but few ask if it is a good idea.

Likewise we can come up with solutions to treat water that otherwise could not be drunk, but, that may not always be the best of ideas. Adding to the challenge is that planning by drinking water, wastewater, and electric utilities occurs separately and is not integrated. Both sectors need to manage supplies for changes in demands throughout the year, but because they are planned for and managed separately, their production and use are often at the expense of the natural environment.  Conflicts will inevitably occur because separate planning occurs (for a multitude of reasons, including tradition, regulatory limitations, ease, location, limited organizational resources, governance structure, and mandated requirements). However, as demands for limited water resources continue to grow in places that are water limited, and as pressures on financial resources increase, there are benefits and synergies that can be realized from integrated planning for both water and electric utilities and for their respective stakeholders and communities. The link between energy and water is important – water efficiency can provide a large savings for consumers and the utility.   As a result, there is a need to move toward long-term, integrated processes, in which these resources are recognized as all being interconnected .  Only then can the challenges to fully to optimize management of water resources for all purposes be identified.

Anybody have any good examples out there?

Energy Leadership in the Water Industry

January 23, 2013
Climate, Environment, groundwater, infrastructure, Leadership, management, planning, power demands, power-water nexus, sustainability
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Water and energy systems constitute the foundation for modern civilization around the world.  Without water, societies never get started, and without power, it is difficult for economies to grow.  At the same time, modern power generating equipment needs water for cooling and processes, creating an interdependency between water and energy infrastructure and potential for conflict over water resources. As a result, the Energy-Water Nexus is a topic of great interest and discussion among federal policy-making and regulatory entities; private and public sector water and electric utilities; state and local governments, and many supporting technical, educational, professional associations. At the nexus of water and energy exists a host of societal issues, policy and regulatory debates, environmental concerns (local and global), technological challenges, and economic impacts that must be balanced or optimized to permit ongoing economic development for all (NETL, 2008).

Estimates indicate that from 1950 to 1980, demands for water increased steadily across all sectors, with 1980 being the peak water use year.  However, since 1980, withdrawals declined.  Despite the overall decline, the built environment demands continued increase. This of course ignore the natural environment demands, which may play a large part in the economic stability of some regions.  Unlike water demands, the total US power consumption continues to climb as a result of population increases.  The US Census Bureau (2004) projects that the national population will increase from 282 million people in 2000 to 420 million by 2050.  The Energy Information Administration (EIA) project, assuming the latest Census Bureau projections in its reference case, the U.S. population to grow by about 70 million in the next 25 years and electricity demand to grow by approximately 50 percent (EIA, 2006). More people, means more power.  More power means more water for cooling unless all new power is solar or wind, something highly unlikely.  On the current track, which suggests and expansion of fossil fuel plants, the power sector may be highly vulnerable to changes in water resources, especially those that are already occurring, and are likely to intensify, as result of climatic changes (Vorosmarty et al 2000, Bates et al 2008, Dai 2010, NETL 2010d).

Adding to the challenge is that planning by drinking water, wastewater, and electric utilities occurs separately and is not integrated. In the US, the energy sector uses 39% of the water withdrawals on an annual basis for cooling, immediately behind the 40% used by agriculture (Lisk et al, 2012; GAO, 2012).  Urban demands (12.6% of water use – Sanders and Webber, 2012) require clean water supplies to protect public health.  Both sectors need to manage supplies for changes in demands throughout the year, but because they are planned for and managed separately, their production and use are often at the expense of the environment (NREL, 2011). This separate planning occurs for a multitude of reasons, including tradition, regulatory limitations, ease, location, limited organizational resources, governance structure, and mandated requirements. However, as demands for limited water resources continue to grow among all sectors, and as pressures on financial resources increase, there are benefits and synergies that can be realized from integrated planning for both water and electric utilities and for their respective stakeholders and communities. The link between energy and water is important – water efficiency can provide a large savings for consumers and the utility.  Reduced energy consumptions benefits the consumer – but should always be considered as one of the first steps (Gould, 2011).  As a result, there is a need to move toward long-term, integrated processes, in which these resources are recognized as all being interconnected (NREL, 2011).  Only then can the challenges to fully to optimize management of water resources for all purposes be identified (Scanlon et al 2005).

The lack of planning creates the situation where competition for water between agriculture, power and urban uses will reach a tipping point (or beyond in many basins) as an expected increase in thermoelectric capacity by electric utilities, and an increasing prevalence of droughts could induce possible water shortages.  By 2025, Ciferno (2009) suggests the most vulnerable areas for water shortages are fast growing areas:  Charlotte, NC, Chicago, IL, Queens, NY, Atlanta, GA, Dallas, TX; Houston, TX, San Antonio, TX, and San Francisco.  Immediately behind these areas are Denver, CO; Las Vegas, NV; St Paul MN, and Portland OR (Ciferno,2009). Hightower (2009) notes that virtually all the states west of the Mississippi and many southeastern states will experience regional or statewide water shortages in the coming decade (2010-2020).  The South and the Southwest are particularly vulnerable (Glassman, et al, 2011) because they rely on air conditioning to provide a comfortable environment, which requires more power for a growing population, requiring more water for cooling power plants.

These projections come with recent experience that is likely to foretell the future.  The south, Texas and parts of the west have had repeated drought periods in recent history.  During the summer and fall of 2007, a serious drought affected the southeastern United States.  River flows decreased, and water levels in lakes and reservoirs dropped. In some cases, water levels were so low that power production at some power plants had to be stopped or reduced (Kimmel and Veil, 2009). The Tennessee Valley Authority (TVA) Gallatin Fossil Plant is not permitted to discharge water used for cooling back into the Cumberland River due to thermal pollution (water > 90 F) (WSMV Nashville 2007; Kimmel and Veil, 2009; NETL 2009c).  Nuclear and coal-fired plants within the TVA system were forced to shut down some reactors (e.g., the Browns Ferry facility in August 2007) and curtail operations at others. This problem has not been limited to the 2007 drought in the southeastern United States. A similar situation occurred in August 2006 along the Mississippi River (Exelon Quad Cities Illinois plant).  Other plants in Illinois and some in Minnesota were also affected (Union of Concerned Scientists 2007). The production of gas from oil shale and biofuels has exacerbated the issues in the Plains states (Kansas, Oklahoma, Texas), Upper Rocky Mountains, and the Ohio River Valley (Hightower, 2009; Kimmel and Veil, 2009).  DOE (2006) specifically identifies where new power plants have been opposed because of potential negative impacts on water supplies (Tucson Citizen, 2002; Reno-Gazette Journal, 2005; U.S. Water News Online, 2002 and 2003; Curlee, 2003). Recent droughts and emerging limitations of water resources have many states, including Texas, South Dakota, Wisconsin, and Tennessee, scrambling to develop water use priorities for different water use sectors (Clean Air Task Force, 2004a; Milwaukee Journal Sentinel, 2005; GAO, 2003; Curlee, 2003; Hoffman, 2004; U.S. Water News Online, 2003)

So what is currently happening?  Current legislation  is mostly silent on the power-water nexus.  This is not to say that little is being done. A number of federal agencies are actively involved with the power-water nexus, including DOE, via NETL, and NREL, NOAA, USEPA via water Wise and Energy Star, BLM though management of land and water resources in the west, USDA and Department of the Interior/USGS which inventories water supplies.  However, DOE (2006) noted that collaboration on energy and water resource planning is needed among federal, regional, and state agencies as well as with industry and other stakeholders.  GAO (2012a) notes that the growth in water and energy demands is occurring at a time when the nation’s supplies are stressed by a growing population, a variety of new and changing uses, and environmental challenges such as climate change, but none of the involved agencies consistently or strategically collaborate on to ensure a harmonized approach to energy and water resource planning.

Effective integrated energy and water policy planning will require identifying the individual and cumulative impacts that power plants have on water resources and the vulnerabilities of specific power plants to changes in water resources (Wilkinson 2007, Scott and Pasqualetti 2010;Stillwell et al 2011; Kenney and Wilkinson 2012). From a systems perspective, a sustainable society is one that has in place the institutional, social and informational mechanisms to keep in check the feedback loops that cause exponential population growth and natural capital depletion.  A sustainable world is not a rigid one, where population or productivity is held constant.  Yet sustainability does require rules, laws and social constraints that are recognized and adhered to by all (Meadows, 2005).   Integrated planning implies removing silos, working collaboratively, and using resources wisely. It implies using the combined intelligence of multiple parties in the planning and fulfillment of goals. It implies linking a vision, priorities, people, and institutions into a flexible system of evaluation and decision-making.  In other words, leadership.

Details on refrences available