Archive for February 2013

It starts with a vision …

February 28, 2013

As an aid to transcending the mental models that pose barriers to deep conservation, it is useful to offer a “vision” of organizing our water infrastructure to pursue that end. Back in 1996, I saw the need to set forth such a vision, conveying what a “decentralized concept” strategy of wastewater treatment and reuse might look like when it was fully developed and in place as the “normal” way of running our water resources management system. I drafted the following piece, looking 20 years into the future to 2016, to offer that vision. Never did get anyone to publish it. That is how uninterested most were in the prospects of water shortages at the time. What about now? It is offered again below, to help you better understand the fundamental transformation of the form and function of our water resources infrastructure that will implement deep conservation and move us toward sustainable water.

By the way, “the droughts of … 2009-2013” – just call me Nostradamus II 😉

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IS “WASTE” WATER RECLAMATION AND REUSE IN YOUR FUTURE?

by David Venhuizen, P.E.

Despite a 1985 report by an engineering consultant which indicated that a system of decentralized, small-scale facilities would be the most cost efficient, environmentally benign, and societally responsible way to manage wastewater in the fast-developing Hill Country watersheds, the City of Austin has continued to extend conventional, centralized sewer service to that area.  The institution of a project to study decentralized management methods, ordered by the Austin City Council in 1993, appears to have done nothing to slow this trend.  Potentially leaky sewer lines and problematic lift stations continue to proliferate in the Lake Austin watershed and in the Edwards Aquifer Recharge Zone and tributary areas, all the while piping water away to be dumped in the river rather than beneficially reusing it.

In the meantime, where on-site wastewater systems – known popularly as “septic” systems – continue to be used, these are treated largely as plumbing projects, focusing on the cheapest way to pipe wastewater underground so it won’t come back to the surface on that lot.  In short, the emphasis has been on making it “go away” with very little concern for what happens when the water – and the pollutants it contains – gets to wherever “away” is.  This despite the environmental sensitivity of these areas, especially the recharge zone and nearby contributing area.  These “plumbing” systems also waste precious water resources.  Methods which are more environmentally sound and more societally responsible are readily available, but regulatory agencies are concerned about their operations and maintenance liabilities.

A solution is to integrate these “better” on-site systems into a decentralized management system which also addresses the needs of higher density development throughout the area.  This “alternative” wastewater management system may be more cost efficient, it would definitely be more environmentally benign, and it would drastically reduce overall water demand.  The importance of the latter in this region is highlighted by the current dry spell.

This begs the question — Can such an “alternative” decentralized wastewater management system actually be practical and workable?  Imagine this scenario.  The year is 2016 …

Jim wheels his electric car into the Uplands Commercial Center.  Got to get to the photovoltaic plant today for a new battery pack, he thinks as he drives over to the center’s management office.  Jim’s official title is Southwest Quadrant Water Reclamation Plant Engineer.  Far less officially, he is known by another title.

“Hey, if it isn’t the turd patrol!” cries Ken, operations manager for the commercial center, as Jim is ushered into his office.  Jim and Ken exchange insults and other pleasantries, then head out toward the back of the complex.

“The water reclamation plant is doing great,” Ken reports.  “We scraped the slow sand filter last week after a 4 month run, as usual.  And we pulled pump number 3 for its annual maintenance checkout.  That’s all we’ve had to do since your last inspection.”

Jim thinks as they walk along about that term, “water reclamation plant”.  They used to be called “wastewater treatment plants” he recalls.  Jim wonders why anyone would have ever thought of this resource as “waste” water.  In his job as the “turd patrol”, he provides quarterly inspection services for industries and commercial management companies that operate and maintain their own reclamation plants, and he is the chief inspector for all the city-owned reclamation plants that serve residential and neighborhood commercial areas.

As he and Ken approach the plant, Jim can’t help but notice the expanse of metal roof gleaming in the sunlight.  He knows that the commercial center’s large rooftop is a major rainwater harvesting facility in this section of town, providing all the water for the center – easy to do since all its “waste” water is reused – and part of the residential water demand in nearby areas.  Overall, rainwater harvesting supplies about a third of the annual water use in the southwest quadrant.

The water reclamation plant isn’t much to look at as Jim walks up to it.  Just concrete boxes and tanks with domes covering them.  The first box is a septic tank.  Water coming out of it is sprayed onto intermittent sand filter beds in the larger tanks.  Water coming out of that filter flows into a holding tank, to be routed through a slow sand filter in the last box, then finally through an ultra-violet light disinfection unit.  Pumps to move water through the system are the only mechanical parts.  The plant is so simple and unobtrusive, Jim thinks, that it’s no wonder Ken never has complaints about system operation.

Water coming out of this plant is practically up to drinking water standards.  But with all the non-potable water demands – toilet flushing, landscape irrigation and cooling tower supply – sitting right there to use the reclaimed water, Jim knows there is no point in further treatment.  He wonders why, back in the 1990’s, it was thought of as intelligent to use drinking quality water for these purposes at the same time all that “waste” water was piped away and – well – wasted, at considerable cost.

Jim marvels that before the “Water Revolution” was started by the City of Austin in the late 1990’s, bringing these simple technologies into broadscale municipal use for decentralized wastewater management, all of them had languished, hardly ever used by cities, even though they had been in existence for over 100 years at that point, and were known to be well-proven, reliable methods.  Times sure have changed, Jim thinks, since people actually thought this “waste” water should all be treated at one large, complex, electricity-hungry plant and then dumped in the river.

The Uplands Commercial Center was the first major project to be installed using this small-scale treatment and reuse concept.  Since then, all development in the southwest quadrant had employed these methods, and even formerly sewered areas had “unhooked” and converted to reuse systems.  Jim recalls the stir that was created, because of concern about aerosols from cooling towers, when Westlake Village became the first development to change over.  But reuse had been proven to be safe by that time, and people soon came to accept it as readily as they had previously accepted the liabilities of frequently overflowing lift stations used in the old centralized management concept.

It doesn’t take Jim very long to give the plant a good “once-over” and take a couple water quality samples.  He trades one last good-natured insult with Ken, then drives to the first of the four quarterly inspections of city water reclamation plants he has scheduled for this day.

As he drives along Bee Cave Road, Jim exchanges a wave with George, a field operator for the Cooperative Council.  Jim recalls how very small-scale reclamation systems – once called on-site wastewater systems – were also integrated into the overall area-wide management system in the late 1990’s. Introduced into this area by a local engineer way back in 1987, sand filter treatment and subsurface drip irrigation “disposal” became the standard small-scale reclamation system for the same reason the Uplands uses these technologies – they are extremely simple and stable.  All the local jurisdictions banded together, forming the Cooperative Council to coordinate management of these systems.  George was no doubt on his way to do semi-annual inspections of some of those small-scale reclamation systems.

On down the road, Jim passes the Lake Point subdivision, one of the last urban fringe developments to use a “waste” water system which mimicked the old centralized strategy – conventional sewers, a package plant, and a land-dumping disposal system.  They thought they were just waiting for a trunk sewer to be built to that area so they could waste their water more “efficiently”.  Jim remembered what a hassle it was dealing with that package plant.  Since it had been replaced with a sand filter plant and a reclaimed water distribution system was installed in 2010, the system had been far easier to manage, not to mention less wasteful.

Jim thinks as he drives along that it’s hard to believe people once had a problem with neighborhood treatment and with reusing reclaimed water for irrigation and toilet flushing, or that industries and commercial developments weren’t expected as a matter of course to recycle or reuse their “waste” water. Nowadays, he reflects, they enthusiastically embrace these concepts because of the water savings they afford.  The droughts of the late 1990’s and of 2009-2013 had a lot to do with that, of course.  By going to extensive reuse, the Austin area had managed to avoid the “water wars” which plagued other area cities until they got smart and did the same thing.  Now, Jim knows, about half of all water demand in the metropolitan area is supplied by direct reclamation and reuse.

But no time for idle thoughts today, Jim realizes.  He still has to inspect the city reclamation plants and get his water samples to the lab, then get the reports of the day’s inspections prepared.  The job is never over till the damn paperwork is done, Jim sighs.  And, oh yes, he still has to get to the photovoltaic plant for that battery pack ….

 

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It’s the infrastructure, stupid!

February 17, 2013

Some of you may remember the unofficial slogan of the 1992 Clinton presidential campaign, “It’s the economy, stupid.” We could paraphrase that as the banner for what we are dealing with here about water, “It’s the infrastructure, stupid.” Or even rearrange that to, “It’s the stupid infrastructure.” Raising the question, of course, just what is stupid about our water infrastructure?

Last year I attended the Texas Water Forum, held at the Capitol Building and moderated by Senator Kirk Watson. A panel of academics, politicians, water agency employees and interest group representatives carried on a discussion of the water future of Texas, centered a good bit on if and how we can implement the State Water Plan. There was much hand-wringing among the panelists about our ability to fund that plan. Afterward, I pointed out to one of the panelists that the State Water Plan has simply presumed that we are constrained to work within the prevailing infrastructure model, that all “solutions” must derive from, at most, tweaking it, that the controlling institutions seem to find “inconvenient” discussion of other infrastructure models. And that is no doubt a good part of the reason for the estimated $53 billion price tag of that plan.

During his introductory remarks, Senator Watson, referring to the volume of communications to his office about water issues, mentioned jokingly that his female aide “drew the line” at dealing with pitches about water-saving men’s urinals. After the Forum ended, by way of saying “hi” to the senator, I asked wryly, why do the urinals in the Capitol use SO much water? I was of course riffing on his comment, but indeed the urinal I used consumes much more water per flush than any urinal I’ve seen in a long time. Senator Watson responded as if the question were “serious” and immediately observed that it really doesn’t make much difference because this flush water could be “purified” and reused. I responded, yeah, but at what cost?

Indeed it would be costly, under present conditions, to reuse the flush water from that urinal as flush water supply in the Capitol. That’s because, under the prevailing water infrastructure model, that water is first sent “away”, in a very expensive system of pipes and lift stations, to a far-off treatment plant before it is treated to a quality that would allow it to be used for flush water supply. So another whole set of expensive, far-flung pipes would need to be installed, and a lot of energy expended (consuming more water to generate it), to get that reclaimed water back to the Capitol.

Sure, we can “tweak” the prevailing infrastructure model to add the reuse pipes. But we could INSTEAD not only install more efficient fixtures, that wouldn’t flush “away” so much of this resource to begin with, we can ALSO retool to an infrastructure model that recognizes the resource value of the water from the very point of “waste” water generation. A model that focuses the majority of our fiscal resources on utilizing this resource near that point, rather than on infrastructure that does nothing but move the stuff around, to make it go “away”. And then spends more to get it back.

Replacing fixtures with more efficient models is the stock in trade of most conservation programs, of course, but changing the infrastructure model appears nowhere on the radar screens of the institutions that plan, design, fund and implement water resources infrastructure. That seems to violate their mental model of how a modern society manages water resources. And because of that, we are gobbling up a lot of fiscal resources doing things the “old” way, resources that could be dedicated to doing a whole lot more to relieve our looming water supply crisis for the same money.

Again, the prevailing model is that water is piped in and the “nuisances” are piped “away”, a model essentially driven by the conditions considered to be paramount in the 19th century. By failing to recognize that the “nuisances” are resources which, if utilized in place, would defray – if not eliminate – the investments required for the piping in and “away”, that infrastructure model features long water loops, entailing many inefficiencies. By employing an infrastructure model that integrates water management functions and so tightens the water loops, we can eliminate much of the inefficiency and so – while not actually creating any water – we do more with less water, AND do it at less cost.

We need to design water sustainability into the very fabric of development, not attempt to append it on, as if an afterthought rather than a prime goal.

Let’s look at an example, the sort of “waste” water infrastructure model to which the institutional infrastructure defaults. A small but growing Central Texas city (that shall remain nameless to protect the guilty), currently generating about 0.7 million gallons per day (MGD) of wastewater flow, is going to install a new centralized wastewater treatment plant sized for the 1.7 MGD flow projected to be generated at the end of 20 years of forecast growth of that city. Right off the bat, this is economically inefficient, because a significant portion of that additional 1 MGD of capacity would not be utilized for many years. Indeed, if the water supply issues of this region – issues which this make-it-go-“away” strategy will exacerbate – limit the water available to serve that projected growth, some of that capacity may NEVER be used. It would be far more economically efficient to add treatment capacity in small increments on a “just in time” basis, as needed to serve only the development that is actually imminent. And by using distributed systems that integrate reuse of the reclaimed water right into the very fabric of the development, they would defray use of the “original” water supply to serve non-potable demands, and so enhance the prospects that water would be available for that growth.

Exactly because all the wastewater would be gathered at one point, that city insists it “needs” the ability to discharge to surface waters, even as it purports its intention is to route the treated wastewater to irrigation reuse. But reuse opportunities near the treatment plant would be quite limited, and additional fiscal resources would be required to pipe that reclaimed water to points of use in other areas of the community. Where that money would come from is an open question, so the city knows that choosing this infrastructure model has “condemned” it to discharge as its prime “disposal” option, with reuse PERHAPS coming on line at some undetermined time to utilize this water resource.

The decision to discharge in turn imparts the “need” to add something like $10 million to the treatment plant cost in order to remove nutrients, due to the sensitive nature of the receiving waters. In societal terms, this is an utter waste of that added expense. Those nutrients would also be resources if the reclaimed water were routed to irrigation reuse, so this is really a doubling up of the waste of resources.

Then add on that it is not known where in and around this city the additional 1 MGD of flow would be generated relative to the treatment plant location. The facilities needed to make it go “away” from those locations to this plant would be another additional cost, currently unaccounted for. The presumption no doubt is that “growth will pay for it”. So installing and upgrading conveyance facilities would add those costs, along with the cost of treatment plant capacity, to the price of creating that development. This is cost that could be pretty much avoided by expanding the treatment capacity a small increment at a time in distributed facilities, within or very near the development. This is another manner in which the prevailing infrastructure model is economically inefficient.

The upshot is that some, perhaps much, maybe even most, of this “waste” water will truly be wasted, at great cost, while this city attempts to find replacement water and to pipe it to the new development to provide irrigation and other non-potable uses. In this community, where that water would be found is an open question.

All these inefficiencies will be built into the city’s infrastructure because it appears that the city leaders cannot step outside their mental model, that they believe they “must” institute the form of infrastructure prescribed by the controlling institutions. Thus they will fail to actually maximize the reuse opportunities, so saving much of that water to help serve the growth they have forecast as the reason for making the infrastructure investments to begin with.

Tragically, and predictably, none of the institutional infrastructure that is supposed to be looking out for society’s best interests ever even suggested to this city the “density” of such an attitude. Certainly, neither TCEQ nor TWDB ever questioned this waste of water and money, rather – also prisoner to their mental models – they act as if what this city proposes is exactly how society “should” be addressing its water resources infrastructure. Indeed, TCEQ – dedicated to a rule system that makes wastewater management all about “disposal” rather than resource management – would resist permitting a distributed management concept. Sadly, it seems that “institutional convenience” is a far more highly rated value than is the actual point of making these investments, to attain a safe and sustainable water supply.

This same pattern is being repeated in and around every city in the state, as water resources infrastructure is being planned, designed, funded and installed to serve growth. An abiding tragedy of continuing to prop up this prevailing infrastructure model, despite the many ways it is inefficient, is that because we are dealing here with infrastructure that has a long service life, we are literally cementing in place this inefficient management model for decades to come.  We’re doing this simply because it seems to be “institutionally inconvenient” to question that infrastructure model.

So clearly there is ample reason to question if a State Water Plan that is predicated on extending and perpetuating the prevailing 19th century infrastructure model would cost more than it needs to, if we were to instead pursue a smarter infrastructure model, a model that recognizes and responds to the water realities here in the 21st century. An infrastructure model that yields deep conservation. But of course, unless/until the institutional infrastructure that plans, designs, funds and implements water resources infrastructure can transcend its mental model and become willing to so much as put on the table for discussion the infrastructure model it pursues, it will be very problematic to generate a plan which gets us on a path to sustainable water, at any cost.

There are opportunities just about everywhere we look for designing sustainable water into the very fabric of development, opportunities that are being blunted by existing institutional arrangements. It’s like the controlling institutions are FAR more concerned about perturbing the status quo than they are about the sustainability of this society.

And that is why, “It’s the infrastructure, stupid.”

 

First ‘Logue in the Water

February 12, 2013

Mental Models – The Great Misleader

I was riding my bicycle one day awhile back when a pickup truck came past, whereupon the driver stuck his arm out the window and yelled something at me that I heard as a ewe-see-kay sound. I was about to raise my own arm in a one-finger salute when I saw that his hand was in a fist, not such a salute, and it sunk in what he had actually said. I realized I was wearing my University of Wisconsin cycling jersey, and the driver had yelled, “Go Bucky!” As in Bucky Badger, the mascot of the Wisconsin Badgers. I had nearly fallen prey to my mental model.

A mental model is an explanation of someone’s thought process about how something works in the real world. It’s a representation of the surrounding world, the relationships between its various parts, and a person’s understandings and perceptions about all that, a device our brains use to create a “shortcut” to interpreting input from our environment. This being Texas, as any experienced road cyclist will tell you, when someone yells a ewe-see-kay sound at you, it’s almost invariably a crude and unfriendly invitation to get off the road. Thus, we cyclists have that mental model of those drivers.

As I learned from the incident on my bike, if your mental models are followed in knee-jerk fashion, they can lead you to very wrong conclusions. A lot of what we’ll be doing in this blog is challenging mental models about water resources management. Mental models that, it will be argued, lead even very seasoned professionals in the field to wrong conclusions. Indeed, perhaps especially seasoned professionals, simply because they presume their model is undeniably correct, and so refuse to test it.

Deep Conservation, the Surest Path to Sustainable Water

Another concept we’ll consider is “deep conservation”. The stock in trade of water conservation programs practiced by cities and other water supply entities only tinkers around the margins of the basic water management infrastructure system; they do not attempt to fundamentally alter that system. These programs mainly consist of urging the use of more water efficient fixtures and less water use for irrigation. Savings from these sources are largely dependent on behavior, so consistent delivery of a “firm yield” of conserved water supply would require a vigorous outreach, surveillance and enforcement effort, a “meddling” in activities being carried out on private property which most water supply entities have so far not evidenced the will to do. So this sort of conservation is rather “shallow”.

But what we need, if we are to approach sustainable water, are dependable, enduring long-term savings that are inherent in our water management processes. To get there, we need to get more deeply into how we manage water, and to fundamentally reform those processes. One is not likely to be inclined to get into all that, however, unless one understands why we should undertake that fundamental reform.

The prevailing water resources infrastructure model is largely informed by the conditions considered to be paramount in the 19th century; in particular, these practices are largely focused on making what are perceived to be nuisances to go “away”. But today we need systems rooted in the realities of the 21st century, systems that address all water as a RESOURCE.

This is indeed an emerging awareness within the mainstream water engineering community, as set forth, for example, in the preface to Cities of the Future, written by Paul Brown of Camp, Dresser, McKee – a voice from the very heart of the mainstream. Brown calls presently prevailing practice the “fourth paradigm” of water resources management. We won’t go through the whole history lesson here, rather will just note that Brown’s “third paradigm” began in the mid-19th century, when the industrial revolution caused explosive growth of cities, creating squalor that resulted in rampant water-borne disease. The solution adopted was to pipe the stuff “away”.

Later, it was realized that, at “away”, our rivers and streams were being transformed into foul open sewers, and so treatment at the end of the pipe was incorporated, creating the “fourth paradigm” of management. Brown noted the fundamental inefficiency of this exclusive use of end-of-pipe control, stating, “… no matter how much money is spent to reduce controllable regulated sources of pollution, the integrity of water bodies has been severely impaired and will remain so if the fast conveyance, end of pipe treatment paradigm alone continues to be the prevailing model.” In terms of water quantity, this model pipes in water and pipes out “wastes”, both wastewater and stormwater runoff – which are resources if managed properly – creating long water loops.

Brown then introduced the concept of sustainable development and postulated that, in terms of water management, moving toward sustainable development will require that we “tighten up” these water loops. He states, “[In the future] all components of water supply, stormwater, and wastewater will be managed in a closed loop. … Closing the water loop may require decentralization of some components of the urban water cycle in contrast to the current highly centralized regional systems employing long distance water and wastewater transfer.” [emphasis added] Brown terms this new, tighter-looped infrastructure model the “fifth paradigm” of water resources management, and he asserts this is where society needs to be headed.  As do I.

Ways we can move to this “fifth paradigm” and benefits that will accrue include:

  • Hook up supplies more directly with demands, through strategies like building-scale rainwater harvesting and project-scale “waste” water reclamation and reuse, to create short water loops.  New developments – both infill and out in the hinterlands – could use those project-scale “waste” water systems to cost efficiently maximize reuse of this water resource in or near the development.  Do this instead of spending huge sums on pipelines to make the loops larger, to make resources that are being perceived as nuisances go “away”, so that the only way to accomplish reuse is spending even more on reclaimed water pipelines to get that resource back from “away” to serve those demands in or near where the flow was generated to start with.
  • Design water management strategies that focus on efficient utilization of water into the very fabric of every development – green infrastructure, rainwater harvesting, project-scale “waste” water reuse, etc. – instead of appending on, as if an afterthought, management strategies that focus most of the investment on just moving water to and away from the development.  If we do this, we may never have to build another trunk main, saving untold amounts of public money.
  • For example, there is no reason why every commercial building shouldn’t be required to derive all their non-potable water needs from project-scale rainwater harvesting and “waste” water reuse, as for example is absolutely required by the Living Building Challenge.
  • Manage stormwater to hold at least as much water on the land as remained there under natural conditions, by using Low-Impact Development (LID) strategies that focus on retention and infiltration, rather than running it to an end-of-pipe pond, and thence to “away”.  We need to stop, and reverse, the “desertification” of the city.
  • Many of these actions will also significantly lower the amount of energy required to run the water management infrastructure, producing significant fiscal savings. This will also provide significant reductions in greenhouse gas emissions.  And, since it takes a lot of water to produce energy – the “water-energy nexus” – these energy savings will also save a lot of that water.

Adoption of this “fifth paradigm”, decentralized infrastructure model of shorter water loops will blunt or eliminate the water use inefficiencies that are inherent in the long-looped prevailing “fourth paradigm” model. If we stop addressing so much of the water that flows through our communities as a nuisance, to be made to go to that magical place we call “away”, and start addressing it as a resource, the water conservation we can obtain would dwarf the savings expected from those “shallow” conservation programs. This is “deep conservation” – the sort of thing that, as we progressively adopt it, can actually keep our water use flat for years to come, even as the population we need to serve grows.

That fundamental alteration of the form and function of our water resources infrastructure will be a generational change, happening one project at a time over many years.  But we are dealing here with infrastructure that has a very long service life, and the decisions we make today will be with us for decades to come, with the sunk cost in that 19th century model “condemning” us to continuing to bear those inefficiencies.  So we have to start making those changes now, in every project going forward, to get on that path to deep conservation.

These ideas, ideals, principles and concepts are the subject of this waterblogue – a blog that is a dialogue about water.  In particular, about moving society toward sustainable water.

Let the conversation begin.