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When do we get serious about sea level rise?

March 18, 2013
Banking industry, Climate, Development loans, Environment, finance, groundwater, infrastructure, Insurance, Leadership, management, planning, sanitary sewer, sea level rise, stormwater, sustainability, Tidal flooding, Uncategorized, water sewer management, water supplies
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Based on my last blog, his inquiry came to me.  And I think I actually have an answer:  when bakers and insurance companies decide there is real exposure.  Let’s see why it will take these agencies.  There is very little chance, regardless of good faith efforts, significant expertise, or conscientious bureaucrats to stop growth and development.  The lobby is simply too strong and local officials are looking for ways to raise more revenues.  Development is the easiest way to increase your tax base.  As long as there are no limits placed on develop-ability of properties (and I don’t mean like zoning or concurrency), development will continue.  But let’s see how this plays out.  Say you are in an area that is likely to have the street inundated permanently with water as a result of sea level rise (it could be inland groundwater, not just coastal saltwater).  For a time public works infrastructure can deal with the problem, but ultimately the roadways will not be able to be cleared.  Or say you are located on the coast, and repeated storm events have damaged property.  In both cases the insurance companies will do one of three things:  Refuse to insure the property, insure the property (existing) only for replacement value (i.e. you get the value to replace) but no ability to get replacement insurance, or the premiums will be ridiculous.  We partially have this issue in Florida right now.  Citizen’s is the major insurer.  It’s an insurance pool created by the state to deal with the fact that along the coast, you cannot get commercial insurance.  So Citizens steps in.  The state has limited premiums, and while able to meet its obligations, in a catastrophic storm would be underfunded (of course in theory is should have paid out very little since 2006 since no major hurricanes have hit the state, but that’s another story). 

As the risk increases, Citizens and FEMA, the federal insurer, have a decision to make.  Rebuilding where repeated impacts are likely to happen is a poor use of resources and unlikely to continue.  Beaches and barrier islands will be altered as a result.  The need will be to move people out of these areas, so the option above that will be selected will be to pay to replace (move inland or somewhere else).  Then the banks will sit up.  The banks will see that the value of these properties will not increase.  In fact they will decline almost immediately if the insurance agencies say we pay only to relocate.  That means that if the borrowers refuse to pay, the bank may not be able to get its money out of the deal on a resale.  We have seen the impact on banks from the loss of property values as a result of bad loans.  We are unlikely to see banks engage in similar risks in the future and unlikely to see the federal insurers (Fannie Mae, Freddie Mac) or commercial re-insurers like AIG be willing to underwrite these risks.   So where insurance is restricted, borrowing will be limited and borrowing time reduced.  That will have a drastic impact on development.  The question is what local officials will do about it?

There are options to adapt to sea level rise, and both banking and insurance industries will be paying close attention in future years.  Local agencies will need a sea level rise adaptation plan, including policies restricting development, a plan to adapt to changing sea and ground water levels including pumping systems to create soil storage capacity, moving water and sewer systems, abandoning roadways, and the like, and hardening vulnerable treatment plants.  Few local agencies have these plans in place.  Many local officials along the Gulf states refuse to acknowledge the risk.  What does that say about their prospects?  Those who plan ahead will benefit.  Southeast Florid a is one of those regions that is planning, but it is slow process and we are only in the early stages.

Groundwater Accelerates Sea Level Rise

March 14, 2013
Climate, communciations, Development loans, Environment, funding, groundwater, infrastructure, Insurance, Leadership, management, planning, sea level rise, stormwater, sustainability, Tidal flooding, Uncategorized
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Regardless of the causes, southeast Florida, with a population of 5.6 million (one-third of the State’s population), is among the most vulnerable areas in the world for climate change due its coastal proximity and low elevation (OECD, 2008; Murley et al. 2008), so assessing sea level rise (SLR) scenarios is needed to accurately project vulnerable infrastructure (Heimlich and Bloetscher, 2011). We know that sea level has been rising for over 100 years in Florida (Bloetscher, 2010, 2011; IPCC, 2007). Various studies (Bindoff et al., 2007; Domingues et al., 2008; Edwards, 2007; Gregory, 2008; Vermeer and Rahmstorf, 2009; Jevrejeva, Moore and Grinsted, 2010; Heimlich, et al. 2009) indicate large uncertainty in projections of sea level rise by 2100. Gregory et al. (2012) note the last two decades, the global rate of SLR has been larger than the 20th-century time-mean, and Church et al. (2011) suggested further that the cause was increased rates of thermal expansion, glacier mass loss, and ice discharge from both ice-sheets. Gregory et al. (2012) suggested that there may also be increasing contributions to global SLR from the effects of groundwater depletion, reservoir impoundment and loss of storage capacity in surface waters due to siltation. The loss of groundwater, mainly from confined aquifers, is troubling, and currently completely unknown. The contribution of carbon dioxide, commonly occurring in deep groundwater is also unknown. To gauge the risk to property in southeast Florida, Southeast Florida Regional Climate Compact and Florida Atlantic University reviewed twelve different projections of SLR and its timing. The consensus was 3” to 7” by 2030 and 9” to 24” by 2060. From the literature review and analysis, it was concluded that approximately 3 ft. of sea level rise by 2100 would a suitable scenario and time frame to illustrate the methodology presented in this article. To allow flexibility in the analysis due to the range of increases within the different time periods, an approach that uses incremental increases of 1, 2, and 3 feet of SLR was considered for risk scenarios. An issue normally ignored in sea level rise projections is groundwater. The importance of the groundwater table in the model is that it is responsible for determining the soil storage capacity. Soil is composed of solids, water, and air (voids). Soil storage capacity depends on physical and chemical properties, water content of the soil, and depth to the water table or confining unit (Gregory et al 1999). As the rain infiltrates the soil, unsaturated pores quickly fill up, effectively raising the water table (Gregory et al 1999). For example efforts, a groundwater surface elevation map was derived based well site information available from the USGS (http://groundwaterwatch.usgs.gov) that had a minimum of 35 years of continuous data. Using GIS, an inundation model was created in GIS by subtracting the groundwater surface model from the digital elevation model with the difference in elevation being the soil storage capacity. The photo shows the evolution of these features as applied to a section of northwestern Miami-Dade County. What this indicates it that the impact of sea level rise on low-lying inland areas may be far different that the projections using the bathtub models. It also means that wellfields, sewer mains, roadways and storm water systems will be affected far more quickly than projected from bathtub models. The method used here suggested that the estimated may be off by a factor of two of three.

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

SUSTAINABILITY THROUGHOUT TIME – BUT NOW WHAT?

January 10, 2013
communciations, Environment, finance, groundwater, infrastructure, Leadership, management, Marketing water, planning, sustainability, Uncategorized, water supplies
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I was cruising through Glacier Bay National Park when I wrote this blog.  It was just one of those inspirational momentsl  If you have never seen it, you should, especially as a water professional.  The entire park is a testament to the power of water and the result of changes in climate cycles that affect the hydrologic cycle.  I will post video of the journey separately, but suffice it to say that the inherent beauty of the place is difficult to describe.  Needless to say with a large concentration of glaciers in the area (most retreating), there is copious amounts of water (for now).  The Pacific Glacier has retreated 65 miles, yes MILES, in 300 years in part because of changes in oceanic moisture and evaporation.  The native people, Tlingets, moved and survived based on glacier flows end ebbs.  But that’s not my point.  Seeing this much water leads to an entirely different perspective, one that is helped by Brian Fagan’s book, Elixir which outlines the history of civilizations as they were affected by harnessing of water, or the lack of ability to do so.  Same thing applies to the Tlingets here.

Historically the key was to rely on surface waters where they were consistent, to manage water locally and carefully for the benefit of all, and when surface waters were not consistent enough to be reliable year after year, quanats, shallow wells and other mechanisms were used to extract water from glacial till or adjacent to rivers (riverbank filtration or infiltration galleries in today’s vernacular).  Or people moved or died out. The ancient people did not have the ability to dig too deep, but were creative in means to manage available supplies.

Contrast this to today where over the last 50 years we have been able to extract water from ever expanding, generally deeper sources, but to what end?  Certainly we have “managed “ surface waters, by building dams, diversions and offstream reservoirs.  These supply half the potable water use in the United States and Canada as well as a lot of irrigation.  But groundwater has been an increasing component.  Fagan makes the point that deep groundwater sources are rarely sustainable for any period of time, and that many in the past have recognized this limitation.  But have we?

Maybe not so much.  A couple years ago I was at a conference out west.  The session I was speaking at involved sustainable groundwater, a major issue for AWWA, ASCE, NGWA and the utilities and agricultural folks around the world.  One of the speakers was a geologist with the State of Utah.  Her paper concerned the issues with decreasing groundwater levels in the St. George and Cedar City, areas in southwestern Utah, where population growth is a major issue.  Her point was that despite the State efforts, they had significant drawdowns across the area.  Keep in mind that the USGS (Reilly, et al, 2009) had identified southwestern Utah as one of many areas across the US where long term decreasing groundwater levels.  My paper was a similar issue for Florida, so I stopped partway into my paper and asked her a question:  has any hydrogeologist or engineer trying to permit water in the area ever said the water supply was not sustainable?”  The room got really quiet.  She looked at me and said, “well, no.”  In fact the audience chimed in that they had never heard this from their consultants either.  The discussion was informative and interesting.  Not sure I really finished my presentation because of the discussion.

To be fair, consultants are paid to solve problems, and for water supplies, this means finding groundwater and surface water limited areas like Utah when their clients request it.  So you don’t expect to pay your consultant to find “no water.”  But where does that lead us?  The concept of sustainable yield from confined aquifer systems is based on step drawdown tests.  Ignoring the details, what this constitutes is a series of short term tests of the amount of drawdown that occurs at different pumping levels. AWWA’s manual on Groundwater can give you the details, but the results are short-term and modeling long-term results requires a series of assumptions based on the step drawdown test.  This is that had been submitted in support of permits in Utah (and many other places).  As discussed in the conference session, clearly there is something wrong with this method of modeling and calculation because, well, the results did not match the reality.  The drawdowns increased despite modeling and step drawdown tests showing the demands were sustainable.  Clearly wrong.  Competing interests, the need to cast a wider net, and many other issues are often not considered.  The results play out throughout the world.  Confined aquifers are often not sustainable, a potential problem for much of agriculture in the farm belt of the US.  Are we headed the same direction as ancient people?

The good news is that these same hydrogeologists and engineers have the ability to help solve the sustainability problem.  We need a new definition for “safe yield.”  We need a better means to estimate leakance in aquifers.  A project I did with injection wells indicated that leakance was overestimated by a factor of 1000 to 10,000, which would drastically alter the results of any model.  More work needs to be undertaken here.  The overdraw of confined groundwater is a potential long-term catastrophe waiting to happen.  And the consequences are significant.  The question is can we adapt?

But when we start to look at resource limitations, who stands up and says, this type of withdrawal is not the right answer.  We need another one.  Where is that leadership moment?

Cutting costs while keeping the stormwater out

November 3, 2012
finance, funding, groundwater, infiltration, inflow to sanitary sewer, infrastructure, management, sanitary sewer, stormwater, sustainability, water sewer management
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Storms highlight the need to reduce infiltration and inflow into the collection system so as not to overwhelm the piping system causing plant damage or sewage overflows into streets, so much of the focus has been on dealing with removal of infiltration and inflow through televising the sewer system and sealing or lining sections where leaks are noted.  However, many miles of videotape show virtually nothing, so significant money is spent to find “nothing.”  Part of this is because “infiltration” and “inflow” are not the same, and storm events do not highlight infiltration nearly as much inflow.

The manholes and clean-outs are required for access and removal of material that may build up in the piping system and for changes in direction of the pipe.  Manholes are traditionally pre-cast concrete or brick, with brick being the method of choice until the 1960s.  Brick manholes suffer from the same problems as vitrified clay sewer lines – the grout is not waterproof so the grout can leak significant amounts of groundwater.  The manhole cover may not seal perfectly, becoming another source of infiltration.  Pre-cast concrete manholes resolve part this problem, but concrete is not impervious either.  While elastomeric or bituminous seals are placed between successive manhole rings, the concrete is still exposed.  Many utilities will require the exterior of the manholes to have a coal-tar or epoxy covering the exterior which helps to keep water out.

Inflow results form a direct connection between the sewer system and the surface.  The removal or accidental breaking of a cleanout, unsealed manhole covers, laterals on private property, connected gutters or storm ponds, damaged chimneys from paving roads, or cracking of the pipe may be a significant source of inflow to the system.  All are potential sources of inflow which can be identified easily during storm events.  The peaking that correlates with the rainfall is inflow, not infiltration since infiltration is part of the base flow that creeps upward with time.  When operators see peaks, this is not indicative of infiltration which is groundwater.  Think inflow.   Inflow causes peaks in run time on lift station pumps, and create potential overflows at the plant.  The good news is that simple, low tech methods can be used to detect inflow, which should be the precursor to any infiltration investigation.

The following outlines a basic program for inflow detection and correction for any utility system.  The order is important, and pursuing all steps will resolve the majority of issues.  The first step is inspection of all sanitary sewer manholes for damage, leakage or other problems, which while seeming obvious, usually surprises.  The manhole inspection should include documentation of condition, GPS location, and some form of numbering if not currently available.  Most manholes have limited condition issues, but where the bench or walls are in poor conditions, that should be repaired with an impregnating resin.

Next is repair/sealing of chimneys in all manholes to reduce inflow from the street during flooding events.  The chimney includes the ring, cement extensions, lift rings, brick or cement used to raise the manhole ring.  Manhole covers are often disturbed during paving or as a result of traffic.  The crack between the ring and cover can leak a lot of water.  The intent of the chimney seal is to prevent inflow from the area beneath the rim of the manhole, but above the cone.

The next step is to put dishes into the manholes.  One might think that only manholes in low lying areas get water into them, but surprisingly every manhole dish that is properly installed has water in it.  Hence assume that all manholes leak water between the rim and cover.  Most collection system workers are familiar with dishes at the bottom of the manhole where they are of limited use.  This is because the dish deforms when filled with water or is knocked in when the cover is flipped.  The solution is a deeper dish with reinforcing ribs.  No ribs, don’t use it.  A gasket is required.

Once the manholes are sealed, smoke testing can identify obvious surface connections.  The normal notifications, inspection and documentation will identify broken or missing cleanout caps, surface breaks on public and private property, connection of gutters to the sewer system, and stormwater connections.  All should be documented via photograph, by associated address and public or private location. The public openings at cleanouts can be corrected immediately.  However, if the cleanout is broken, it may indicate mower or vehicle damage, that can occur again.  If missing, the resident may be using the cleanout to drain the yard.  In either case the collection system needs to be protected.  USSI (http://www.elastaseal.com/about_us.html), located in Venice, FL developed a solution, called the LDL plug to correct those commonly broken or commonly opened cleanouts to reduce inflow.

Notices should then be sent to property owners with documentation of the inflow connections to their property.  This is sometimes the most difficult part of the program due to political will, but it is necessary.  This finishes the inflow correction portion of the project, but one more step will help focus efforts for the second “i”.

The final step is a low flow investigation, which is intended to focus on the infiltration piece of the problem.  Such an event will take several days and must be planned to determine priority manhole to start with and sequencing.

Based on a projected plan and route:

  • Open the manholes
  • Inspecting them for flow
  • Determining if flow is significant.  If investigation of basin will end and new basin will be started.  If flow exists, open consecutive manholes upstream to determine where flow is derived from.  Generally a 2 inch wide bead of water is a limit of “significant” infiltration.

Documentation of all problems and corrections in a report to utility that identifies problem, location and recommended repair.  Identification of sewer system leaks, including those on private property (via location of smoke on private property).

The example in Dania Beach, FL was that the last step indicated that only 15% of the sewer system needed to be televised.  This saved the City almost $1.2 million.  Their total costs is under $1.4 million for all parts of the project, spread over several years and contracts.  Overall the hope is that the inflow and infiltration programs together will save $400,000/yr, a five year payback.  But the key is to insure you get the inflow as well as the infiltration… Otherwise storms will continue to overwhelm plants, creating public health concerns and ruining your reuse program.

Sea Level Rise? Or Rising?

October 23, 2012
Astronomical tides, Climate, Environment, groundwater, infrastructure, Leadership, management, sea level rise, stormwater, sustainability, Tidal flooding, water sewer management, water supplies
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October is the month that brings us the astronomical tides, or locally to the coasts, the annual high, high tide.  The position of the moon relative the Earth creates a slight alteration in the gravitational pull of the moon on the oceans so high tide, is, well high!  If you lived in a coastal areas, what did you see?  Or experience?  Southeast Florida was rife with email chatter and photographs of flooded streets, yards, and canals.  The City of Fort Lauderdale sent notices to residents warning them about the tides.  We had no rain, just the tide coming in.  These are low lying areas that 20 years ago did not flood except during storms.  This is just a phenomenon that has been monitored in coastal areas over the past 5-10 years, depending on the complaints that have come into local officials.

One of the more interesting complaints I received in my career was in Hollywood Florida where a resident complained about the “fish in the street.”  Sure enough, the storm drain in front of his house was connected directly to the Intracoastal waterway and the October tides had pushed the saltwater up through the catch basin into the street.  Now these weren’t snook or redfish, they were little fish escaping the snook and redfish, about 3-5 inches long.  Pretty funny stuff if you think about it.  Realizing the problem, I called him 3 hours later and asked if the problem had been solved.  He said told me I was a genius to fix that so fast.  My boss told me to take advantage of luck and drop the explanation, but to design a solution (which we did).  My boss was right, but the call made me more cognizant of the issue.

15 years later, I have a student developing models of what happens during the annual high and average tides, especially with respect to the potential for flooding in low lying areas where groundwater is just below the surface.  His work is impressive.  A lot more land, especially inland, may flood as a result of the annual tides, which are a precursor to the long term trend of rising seas.  See the groundwater has a slight upward gradient as you move inland.  As a result, you cannot use the tide levels to predict inland flooding, you need to add the tides on top of historical groundwater levels.  Of course the wet season is the summer in Florida, so the October tides come just at the time groundwater levels are highest.  But at least we can determine where the stormwater pumping improvements need to go.

Determining where stormwater pumping is needed is only part of the problem.  As sea levels rise, more stormwater management will be needed and a place to put the water will become a problem.  Discharging nutrient laden stormwater to tide is not a good answer when you have fragile reefs offshore.  NOAA’s Florida Area Coastal Environment  (FACE) Initiative outline this (see intensives study – http://www.aoml.noaa.gov/themes/CoastalRegional/projects/FACE/Publications.htm).  Instead, perhaps at some point we may develop infiltration systems to capture this high water table “problem” and convert it to water supplies, solving two issues for southeast Florida.  Might be 2030, but we probably should be doing some planning….

 

If You Manage An Aquifer To Last 100 Years, Does This Demonstrate Good Leadership?

September 29, 2012
communciations, groundwater, infrastructure, Leadership, management, sustainability, water sewer management, water supplies
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Across the United States, we hear the regulatory discussions about managing groundwater supplies.  There are 20 year plans (which many think is the long-term perspective), 50 year plans and 100 year plans; no doubt a myriad of others.  The concept of managing groundwater seems reasonable, but the query here is whether or not managing for a finite period demonstrates good leadership.

In most cases, the concept of managing aquifers for finite periods is associated with the need or desire by local and state officials to develop a certain region, and obtaining the necessary water to meet development projections.  “Sustainability” for elected officials and developers is distinctly different than that of water resource professionals. The whole intent of elected officials and developers is to continue to build more, attract more people and business and, well, to use more water.  This is in contrast to the fact that water supplies in most basins is relatively finite or fixed, which means that inevitably the supply will be exceeded by local demands, the opposite of “sustainability” from a water resource perspective.  Compounding the problem is that water resource professionals are normally pretty creative in stretching finite supplies with reuse, conservation, use policies, restrictions and augmentation with other supplies, actions and programs which actually may work against their long-term goal of sustainability – there is a finite number of reasonable solutions that may work, each with increasing cost to the customers, which works against the goals for the elected officials to limit costs to customers.  As a result, a conflict over the differing views of “sustainability” are inevitable.  As solution requires leadership.

Leadership is understanding that there are constraints to the resources.  Leadership is understanding that there is a limit to the reasonable solutions and a limit to development, or the type of development that can be accommodated.  For example in Colorado, Denver Water, going back 100 years, built tunnels and reservoirs to transfer water from the west side of the Rockies to the east.  This worked for 70 years or so, until the Denver area started to explode, exceeding the capacity of those transfer systems.  As this occurred, groundwater was far less costly than tunnels, reservoirs and acquiring access to water supplies west of the Rockies (and the downstream water delivery contracts impacted this as well).  A 100 year management plan was developed and approved by the State Legislature in 1985 to allow water to be withdrawn from the Denver Basin, despite very limited recharge.  This is not to say that the plan for management was not a good leadership start (certainly it is an improvement over doing nothing), but what happens in 70 years?  We assume some up with a solution to extend the life of the aquifer, but when will that occur and who will lead that charge?   What will be the political backlash when the initial rumblings begin?  The good news is that the major users are utilities, which have resources to pay for treatment, aquifer storage, indirect potable reuse, direct potable reuse and a host of other potential options, but not every basin is so lucky.  If the major users are agriculture or ecosystems, who pays that bill?  If the answer is no one, what happens to the industry?  The jobs?  Communities?  People?

The query begs the question, how do we align competing definitions for sustainability, as defined by local officials, developers, water resource professional and others?  And how do we educate the local officials and the populace of the perils of over-allocation of water supplies?  This is a legacy leadership issue, and it requires hard and sometimes unpopular decisions that can change the course of history.

Legacy leadership is defined by what is left behind not by the current condition.  It’s how we change our thinking and actions to adapt to the changed conditions.  We look back as great water projects of the 20th century – Hoover Dam, the channels carrying water to Los Angeles from the Colorado River and central California that allowed southern California to develop, or the numerous dams across the west that permitted crops to grow in arid regions.  You can search out who led those projects.  That is their legacy.  Those that came afterward reaps the rewards created from the efforts of these leaders.  Now we face a changing condition in the 21st century.  Who will take the 21st century leadership mantle?  And how will we change our viewpoint to protect our resources?  We can start by trying to change the perception of deeper groundwater, especially confined systems, as primary water sources, when they may better serve us in the long-term as back-up or emergency sources in many regions, with surface water as the primary sources.  Where surface waters and surficial aquifers do not exist, perhaps development as desired by local officials is not the sustainable way to go?  So who takes the lead in those areas where there are insufficient resources and tells the developers, no you can’t develop here?  That will be leadership….

 

What is the Risk of Expanding Groundwater Irrigation?

September 26, 2012
Climate, Environment, groundwater, infrastructure, management, sustainability, water supplies
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The demand for more food crops to feed a hungry world has expanded the need for irrigable lands.  Few want to risk the 1930s dust bowl or the droughts of the 1950s, especially with ongoing recurrent drought periods across much of North America on a regular basis.  The access to electricity and modern submersible pumps over the past 80 years has permitted a huge expansion in the amount of irrigation performed with groundwater.  Fly over the western United States and look for “crop-circles” where center wells act as the spoke for rotating irrigation systems.  They are obvious.  But virtually all of them are located in areas where surface water is not available and groundwater is the only source of water available for irrigation.  This might work where the groundwater is surficial, but if the groundwater were surficial and found in large quantities, wouldn’t there be surface waters that intercept the groundwater?  The groundwater would feed rivers, lakes and streams.  But in most places with center pivot irrigation, the groundwater is located well below the surface, and low rainfall means that recharge to these deeper aquifer systems is limited.

Irrigation use accounts for 40% of total water use in the United States.  USGS reports that in Arkansas and Nebraska, 90% of irrigation is groundwater.  These states are two largest groundwater users in the country.  California and Texas are right behind them in total use, with groundwater accounting for 80% of irrigation use.  Idaho, Oregon, South Dakota and Washington are among the states with irrigation accounting for in excess of 90%+ of total groundwater use, although their total use is much less than that of the other four states.  The areas irrigating with groundwater in all of these states competes directly with rural potable users, both individual and small cities, and with ecosystems that may support tourism, fishing, hunting and other outdoor activities.  Unfortunately USGS also reports that in all of these states, there are areas with severe declines in aquifer levels.  For example in South Dakota, USGS estimates that 70% of the water has been withdrawn in 30 years.  So the answer in 20 years will be……  There is no answer at the moment.  Some think we should just drill deeper, but this normally comes with added costs, assuming aquifers actually exist at these deeper levels.  But agriculture can’t afford to pay for treatment, meaning they it will be difficult for them participate in a solution.  Too few people in cities means alternative supplies like reclaimed water are not available.

The irrigation from deeper aquifer that do not recharge readily is indicative of a resource management paradigm that suggests we manage water supplies for a certain period of time (usually our lifetime or work period).  The consequences beyond that timeline are not considered because it is “beyond our lifetime” or planning periods, or we assume “someone will come up with something…”  Non-surficial groundwater supplies throughout the United States and probably the world should be viewed like a scratch-off lottery card.  Once in a while you have a winner, but it’s never enough to sustain you for the long-term, let alone pass it to your kids. And once it is spent, it’s gone.  Likewise once deeper aquifers are drained….  Bryan Fagan suggests most civilizations ultimately failed as a result of water woes.   If we want our civilization to survive well beyond our time, perhaps we should revisit history.

The long-term civilization model suggests we should consider a paradigm shift with respect to non-surficial groundwater.   Non-surficial groundwater is a resource that is finite – water that is stored, but once depleted, cannot be readily replaced.  That is not a sustainable solution and suggests that these types of groundwater sources should not be looked at as primary water supplies for irrigation, or for power or urban or domestic use for that matter – they should be considered back-up sources to protect us from surficial droughts that occur periodically.  The dust bowl impacts would have been lessened if we had back-up irrigation supplies from wells.  But in the future, if the aquifers are dry, and surficial droughts occur, the impact directly affects our food supplies and our economy.  We are often caught in defining the “long-term” as 20 years, but the US is 235 years old, but still considered young.  Our perspective of 20 years as long-term is only a quarter of a lifetime, which clearly falls short of long-term from the perspective of civilization.   Something to think about….