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direct potable reuse


DSCF0032Curtailed water use and conservation are common topics of conversation in areas with water supplies limitations.  As drought conditions worsen, the need for action increases, so when creating a regulatory framework, or when trying to measure water use efficiency, water supply managers often look for easily applied metrics to determine where water use can be curtailed.  Unfortunately, the one-size-fits-all mentality comes with a potential price of failing to fully grasp the consequences decision-making based on such metrics.

One of the issues that water supply regulator like to use is per capita water use.  Per capital water use is often used to show where there is “wasted” water use, such as excessive irrigation.  However such a metric may not be truly applicable depending on other economic factors, and may even penalize successful communities with diverse economic bases.  A heavy industrial area or dense downtown commercial center may add to apparent per capita use, but is actually the result of vibrant economic activity. Large employment centers tend to have higher per capital use than their neighbors as a result of attracting employees to downtown, which are not included in the population.

In south Florida, a recent project I was involved with with one of my students showed that while there was significant variability among utilities, but the general trend of increased economic activity was related to increased per capita use.  Among the significant actors were health care, retail trade, food service and scientific and technical services.  It appears to be these sectors that drive water use upward.  As a result when evaluating the efficiency of a utility, an analysis should be conducted on the economic sectors to insure that water regulations do not stifle economic growth and jobs in a community.   And conversely if you do not have these sectors, you water use should be lower.  Something to think about when projecting or regulating water use.  Limited water use may in fact be limiting economic activity in the area. Of course if you are water limited, limited new withdrawals may be perfectly acceptable if you want to encourage other options, like direct or indirect potable reuse, irrigation, etc.  

It would be interesting to expand this study across the country to see what the national trends look like and how different tourism oriented South Florida might actually be.

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photo 2Over the holidays there were a couple articles that came out about groundwater issues in the US, mostly from the declining water level perspective.  I also read a paper that suggested that rising sea level had a contribution from groundwater extraction, and of course USGS has maps of areas where the aquifer have collapsed as a result of overpumping.  In 2009 USGS published a report that showed a large areas across the country with this issue.  The problem is that of the 50,000 community water systems in the US, 500 serve over 50% of the population, and most of them are surface water plants.  There are over 40,000 groundwater systems, but most are under 500 customers.  Hence, groundwater is under represented at with the larger water associations because the large utilities are primarily surface water, while the small systems are groundwater. AWWA has difficulty reaching the small systems while RWA and NGWA reach out to them specifically.  But the small utility seems more oriented to finding and producing water and operating/maintaining/drilling wells than the bigger impact of groundwater use.  It is simply a matter of resources.  I ran a system like that in North Carolina, and just getting things done is a huge issue.  A couple of my medium size utility clients have the same problem.

The bigger picture may contain the largest risk.  Changing water supplies is a high cost item.  We have seen a couple examples (surface water) as a result of drought.  We saw Wichita Falls and Big Springs TX go the potable reuse route due to drought.  California is looking at lots of options. Both have had rain lately (Wichita Falls discontinued the potable reuse when the reservoir got to 4% of capacity).  Great, but someone is next.  Droughts come and go, and the questions is how to deal with them.

Groundwater supposedly is a drought-proof problem, but is it?  Groundwater has been a small utility solution, as it has been for agriculture.  But aquifer require recharge and water limited areas do not have recharge.  The result is a bigger problem – overpumping.  Throughout the west/southwest, Plains states, upper Midwest (WI, MN, IA), southeast (SC, NC), we see this issue.  Most of these areas have limited surface water so never developed much historically.  Rural electrification changes that because it made is easy to put in an electric pump to pull water out of the ground in areas that never had a lot of water on the surface, and hence were not farmed much. Pumps made is easier to farm productively, which led to towns. However, our means to assess recharge are not very good, especially for confined aquifers. The lowering water levels USGS and state agencies see is an indication that recharge is normally over estimated giving a false picture of water availability.  If your aquifer declines year after year, it is not drought – it is mining of the aquifer. You are sucking it dry like the eastern Carolinas did.  But, like many negative things, there is a lack of willingness to confront the overpumping issue in many areas. There are many states with a lack of regulations on groundwater pumping.  And I still think groundwater modeling use is limited to larger utilities, when smaller, rural systems may be most in need of it due to competing interests.

Concurrently, I think there is a tendency to oversell groundwater solutions (ASR, recharge), groundwater quality and the amount of available water (St George, UT).  Easy, cheap, limited treatment should not be the only selling point.  That leads to some curious decisions like some areas of California north of LA the utilities do not treat hard groundwater – then tell residents they cannot use softeners because of the salt in the wastewater prevents it from being used for reuse.  The reason they do not treat – cost, but it makes things difficult for residents.  The fact is we do not wish to confront is the realization that for many places, groundwater should probably be the backup plan only, not the primary source.

That leads to the question – what do we do about it when every politician’s goal is for their community to grow?  For every farmer to grow more crops?  But can they really grow sustainably?  DO we not reach a point where there are no more resources to use?  Or that the costs are too high?  Or that competition become unruly?  The growth and groundwater use ship is sailing, but in to many cases they do not see the rocks ahead.


 

So everyone is doing their Top 10 questions for 2016 (although with David Letterman off the air, perhaps less so), I figured why not?  So it the vein of looking forward to 2016, let’s ponder these issues that could affect utilities and local governments:

  1. How wild, or weird will the Presidential election get? And part b, what will that do to America’s status in the world?  Thinking it won’t help us.  Probably won’t help local governments either.
  2. Will the economic recovery keep chugging along? Last time we had an election the economy tanked.  Thinking a major change in direction might create economic uncertainty.  Uncertainty (or panic) would trickle down.  Status quo, probably keeps things moving along.  .
  3. What will the “big” issue be in the election cycle and who will it trickle down to local governments and utilities? In 2008 it was the lack of health care for millions of Americans and the need for a solution. Right after the election we got the Great Recession so most people forgot about the health care crisis until the Affordable are Act was signed into law.  And then ISIS arose from a broken Iraq and Arab summer.  None helped local governments.
  4. What are we going to hear about the 20 richest Americans having more assets than the bottom 150 million residents? 20 vs 150,000,000.  And while we are at it, the top 0.1% have more assets than the bottom 90%, the biggest disparity since the 1920s.  While we will decide that that while hard work should be rewarded, the disparity is in part helped by tax laws, tax shelters, lobbying of politicians, etc. as Warren Buffett points out, indicate a discussion about tax laws will be heard.  Part b – if we do adjust the tax laws, how will we measure how much this helps the bottom 99.9%?
  5. What will be the new technology that changes the way we live? Computers will get faster and smaller.  Phones are getting larger.  Great, but what is the next “Facebook”?  By the way the insurance folks are wondering how the self driving car will affect the insurance industry.  So reportedly is Warren Buffett.  Watch Mr. Buffett’s moves.
  6. Along a similar vein, will the insurance industry start rethinking their current risk policies to look at longer term as opposed to annual risk? If so what does that mean for areas where sea levels are rising?  The North Carolina coast, where sea level rise acceleration is not permitted as a discussion item could get tricky.
  7. Will unemployment (now 5%) continue to fall with associated increases in wages? Will that help our constituents/customers?  Will people use more water as a result?
  8. Where is the next drought? Or flood?  And will the extremes keep on coming?  Already we have record flooding in the Mississippi River in December – not March/April?  Expect February to be a cold, snowy month. IT is upper 80s here.  Snowing in the Colorado Rockies.
  9. Will we continue to break down the silos between water “types” for a more holistic view of water resources? We have heard a bunch on potable reuse systems.  More to come there, especially with sensors and regulations.  But in the same vein, will we develop a better understanding of the link between ecosystems and good water supplies, and encourage lawmakers to protect the wild areas that will keep drinking water cleaner?
  10. Will we get water, sewer, storm water, etc. customers to better understand the true value of water, and therefore get their elected official on board with funding infrastructure neglect? And will that come as a result of better education, a better economy, breaking down those silos, drought (or floods), more extreme event, more breaks or something else?

Happy New Year everyone.  Best to all my friends and followers in 2016!


We are all aware of the major drought issues in California this year – it has been building for a couple years.  The situation is difficult and of course the hope is rain, but California was a desert before the big water projects on the 1920s and 30s. Los Angeles gets 12 inches of rain, seasonally, so could never support 20 million people without those projects.  The central valley floor has fallen over 8 feet in places due to groundwater withdrawals. Those will never come back to levels of 100 years ago because the change in land surface has collapsed the aquifer. But the warm weather and groundwater has permitted us to develop the Central Valley to feed the nation and world with produce grown in the desert.  The development in the desert reminds me of a comment I saw in an interview with Floyd Dominy (I think), BOR Commissioner who said his vision was to open the west for more people and farming, and oversaw lots of projects to bring water to where there was none (Arizona, Utah). The problem is that the west never head much agriculture or population because it was hot, dry and unpredictable – hence periodic droughts should be no surprise – the reason they are a surprise is that we have developed the deserts far beyond their capacity through imported water and groundwater.  Neither may be reliable in the long run and disruptions are, well, disruptive.  Archaeologist Bryan Fagan traced the fall of Native American tribes in Arizona to water deficits 1000 years ago.

Yet policymakers have realized that civil engineers have the ability to change the course of nature, at least temporarily, as we have in the west, south, Florida. I often say that the 8th and 9th wonders of the world are getting water to LA over the mountains and draining the southern half the state of Florida. I have lived in S. Florida for 25+ years and am very familiar with our system. The difference though is that we have the surficial Biscayne aquifer and a rainy season that dumps 40 inches of rain on us and LA doesn’t (as a note of caution, for the moment we are 14 inches below normal in South Florida – expect the next drought discussion to ensue down here in the fall). The biggest problems with the Everglades re-plumbing are that 1) no one asked about unintended consequences – the assumption was all swamps are bad, neglecting impacts of the ecosystem, water storage, water purification in the swamp, control of feedwater to Florida Bay fisheries, ….. 2) one of those unintended consequences is that the recharge area for the Biscayne aquifer is the Everglades. So less water out there = less water supply along the coast for 6 million people 3) we lowered the aquifer 4-6 ft along the coastal ridge, meaning we let saltwater migrate inland and contaminate coastal wellfields 4) we still have not figured out how to store any of that clean water – billions o gallons go offshore every day because managing Lake Okeechobee and the upper Everglades was made much more difficult when the Everglades Agricultural Area was established on the south side of Lake Okeechobee, which means lots of nutrients in the upper Everglades, and a lack of place for the lake to overflow, which meant dikes, more canals, etc. to deal with lake levels.

The good news is that people only use 11% of the water in California and Florida, and that Orange County, CA and others have shown a path to some degree of sustainability (minus desal), but the real problem is water for crops and the belief that communities need to grow. When we do water intensive activities like agriculture or housing, in places where it should not be, it should be obvious that we are at risk. Ultimately the big issue it this – no policy makers are willing to say there is “no more water. You cannot grow anymore and we are not going to send all that water to Ag.”  Otherwise, the temporary part of changing nature will come back to haunt us.


A past project I was involved  with involved a look at the feasibility of using wastewater to recharge the Biscayne aquifer In the vicinity of a utility’s potable water supply wells.  The utility was feeling the effects of restrictions on added water supplies, while their wastewater basically unused.  So they wanted a test to see if the wastewater could be cleaned up enough to pump it in the ground for recovery downstream, with the intent of getting added allocations of raw water.  Assuming the water quality issues could be resolved, the increased recovery would solve a number of water resource issues for them, and the cost was not nearly as high as some thought.

So we tested and using sand filters, microfiltration, reverse osmosis, peroxide and ultraviolet light, we were successful in meeting all regulatory criteria for water quality.  The water produced was basically pure water – not constituents in it, and therefore it exceeded all drinking water standards.  We demonstrated that technologically the water CAN be cleaned up.  The only issue is insurance that the treatment will always work – hence multiple barriers and the ground.  This was an indirect potable reuse project and ended because of the 2008 recession and the inability to of current water supply rules to deal with the in/out recovery issues.

The indirect reuse part was the pumping of the water into the ground for later withdrawal as raw water to feed a water treatment plant, as opposed to piping it directly to the head of their water plant.   But recovery of the water can be a challenge and there is a risk that a portion of the injected water is lost.  In severely water limited environments, loss of the supply may not be an acceptable outcome.  Places like Wichita Falls, Texas have instead pursued more aggressive projects that skip the pumping to the ground and go straight into the water plant as raw water.  Technologically the water CAN be treated so it is safe to drink.  The water plant is simply more treatment (added barriers).  So, with direct potable projects, monitoring water quality on a continuous basis maybe the greatest operational challenge, but technologically there is no problem as we demonstrated in our project.

The problem is the public.  You can hear it already – we are drinking “pee” or “poop water” or “drinking toilet water.”  The public relations tasks is a much bigger challenge because those opposed to indirect and direct potable projects can easily make scary public statements.   Overcoming the public relations issue is a problem, but what utilities often fail to convey is that many surface waters are a consolidations of a series of waste flows – agriculture, wastewater plants, etc. by the time they reach the downstream water intake.  Upstream wastewater plants discharge to downstream users.   But the public does not see the connection between upstream discharges and downstream intakes even where laws are in effect that actually require the return of wastewater to support streamflow.  So are rivers not also indirect reuse projects? In truth we have been doing indirect potable reuse for, well ever.

We have relied on conventional water plants for 100+ years to treat surface waters to make the water drinkable.  The problem is we have never educated the public on what the raw waters sources were, and how effective treatment is.  Rather we let the political pundits and others discuss concerns with chemicals like fluoride and chlorine being added to the water as opposed the change in water quality created by treatment plants and the benefits gained by disinfectants.  That message is lost today.  We also ignore the fact that the number one greatest health improvement practice in the 20th century was the introduction of chlorine to water.  Greater than all other medical and vaccine advances (although penicillin and polio vaccines might be a distant second and third above others).   Somehow that fact gets lost in the clutter.

Already the Water Reuse Association and Water Research Foundations have funded 26 projects on direct potable reuse.  Communicating risk is one of the projects.  The reason is to get in front of the issues.  You see, playing defense in football is great and you can sometimes win championships with a good defense (maybe a historically great one, but even they gamble).  Defense does not work that way in public relations.  Offense usually wins. Defenses often crumble or take years to grab hold.

The failure of utilities to play offense, and the failure of elected officials particularly support playing offense is part of the reason we struggle for funds to make upgrades in infrastructure, to perform enough maintenance or to gather sufficient reserves to protect the enterprise today.  And it remains a barrier to tomorrow.   Leadership is what is missing.  It struck me that when looking at leaders, what made them leaders was their ability to facilitate change.  Hence President Obama’s campaign slogan.  But talking about change and making real changes are a little more challenging (as he has seen).  You cannot lead without a good offense, one that conveys the message to the public and one that gets buy-in.  With direct and indirect potable reuse, the water industry has not changed the perception of “toilet water.”  That needs to change.  We need to be frank with our customers.  Their water IS SAFE to drink.  They do not need filters, RO systems, softeners, etc., or buy bottled water, when connected to potable water supplies (private wells, maybe).  We CAN treat wastewater to make it safe, and the technology tis available to make it potable.  . The value they pay for water is low.  Yet in all cases, others, have made in-roads to counter to the industry.  That happened because we play defense.


The number of people that recall the Dust Bowl of the 1930s is dwindling and that may portend poorly for society (likewise the loss of Depression memories and two world wars).  The Dust Bowl was aptly names for the regular storms of windblown dust that pummeled farm fields and blew away valuable topsoil needed by farmers.  Why it occurred was more interesting and foretelling.

The amount of farming had exploded in the late 1920s as a result of  record wheat price, motorized tractors and government programs encouraging farmers to plow up the prairie and plant.  The crops replacing the native plants did not have the same root structure and were less drought tolerant as a result.  When wheat prices collapsed, the fields were left fallow exposing the topsoil to the elements.  Since the topsoil was no longer anchored to the soil by plants, the wind and lack of rain caused much of the topsoil to migrate with the wind as dust.  Topsoil was lost, rain ran off, transpiration decreased, and the cycle just go worse.   Up to 75% of he topsoil was lost.

Rains returned in the 1940s but much of the dry farming (no irrigation) practice was immediately converted to wet framing using deep wells to capture water from aquifers.  The result was healthier crops, more consistent yields and protection of the remaining topsoil as a result.  Or is it?

Visit California today.  They are in the midst of severe drought conditions. Farmers have attempted to protect themselves by drilling more wells – deeper wells which diminish water supplies to the shallower neighboring wells.  Water levels decline, land subsides, the aquifer collapses, and there is little recharge.  Some areas of the central valley have sunk over 8 feet in the past 100 years.  But we have up until this point, had healthier crops and more productive yields, which protects the valley until the rains return.  Or does it?

While the lack of rainfall is a natural cycle, there is an argument to be made that man-made impacts have exacerbated the situation.  In the Dust Bowl states, the initial error was plowing up the native grasses without understanding how they had adapted to the mostly dry conditions on the prairie.  Many of the prairie states receive under 20 inches or rain each year, and scarcely any during the summer, which limited evapotranspiration, which limits thunderstorm and regional rainfall activity.  Less ET = drier conditions.  So growing crops is not what one would immediately identify and a “normal” land use for the prairie.  We altered the environment, but the Midwestern farming thought process doesn’t work in the dry prairie.  Irrigation was needed, but the lack of surface water limited irrigation unless wells are used.  Wells were drilled which returned and improved crop yields, but the well use has caused massive decreases in aquifer levels in the prairie states. The amount of water is finite, so as long as withdrawal exceed recharge, and with only 20 inches of rain that mostly runs off the land, there is a point in time when the well runs dry.  As the well runs drier, productivity will fall.  The interim fix is drill deeper, but the bottom of the aquifer is in sight.  Then, fields will be fallow, agriculture will be impacted dramatically, and it is not inconceivable the Dust Bowl type conditions could reoccur. Policies by man exacerbate the problem because the prairie productivity is accelerated will above its natural condition.

Likewise much of the land subsidence problem in California is irrigation driven – water is pulled through wells in an ever increasing competition to maintain one’s crop yield.  Water wars and fights with one’s neighbors over wells drying up is increasing more common as irrigation needs increase and recharge to the aquifer is diminished.  Much of California is even drier than the Dust Bowl states, and more reliant or wells and irrigation.  Less water also means less ET which means less local rainfall.  So while California has done much to protect itself over the years from drought, the current experience says that declining aquifer levels means we have exceeded the productivity of that state as well.  So is the California Dust Bowl coming?

Man is an ingenious creature.  We overcome much that the Earth throws at us.  But at the same time, we rarely consider the consequences of our actions in overcoming the challenges Earth poses.  These two examples show how our efforts to solve one problem, may actually damage the long term sustainability of these areas.  Short term gain, long term problem.


If you are a wastewater utility, and you create a high quality effluent product that can be used for industrial purposes, irrigation or aquifer recharge, who “owns” the water?  If the utility is sending to a golf course pond for discharge, the answer seems obvious – the golf course owns it.  Not so fast.

Now let’s day you are recharging and aquifer.  You pump it into the ground with the intention of recharging the aquifer to benefit your wellfield.   Or you pump it into an aquifer storage and recovery system with the intent of recovering it when you need it.  Quick impression is that you should own it, but what about the people that sink walls along the way?  Or have existing wells in the vicinity that can tap your injected water?  Can you keep people from pumping it out?  Not as clear.

What about discharge to a stream with the idea of capturing it downstream in an intake system for your water system?  Much less clear.  The ecosystem, farmers, irrigation users, etc. along the stream could use the increased flows.  Can you keep them out?  Very unclear.

Now assume you are a water rights state and there are people who have rights to the aquifer or stream that are more senior to yours.  Can you clip their claim to the water by claiming the water is yours?  Really not clear and the subject of ongoing regulatory discussion and legal proceedings.

There are no clear answers to these questions but they have major long-term impacts of water resource planning in much of the US.  The problem is the rules assume facts not in evidence at the time of the permit (or claim).  Conditions can change – permits and rules may not (or have not).  Maybe the water regulations and that the changed condition should perhaps obviate the prior claim?  A very tough legal issue and one bound to make a bunch of people unhappy.  The concept of reclaiming water from waste was not a consideration in the past, so clearly the rules that cover reclaimed water need to be revised.  I can’t wait to see the results.

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