Archive for November 2018

A space traveler lands in Austin …

November 26, 2018

In 1999, I gave a presentation at an EPA-sponsored conference on urban infrastructure, featuring “visionaries” focusing on where we were expected to be headed to deal with water resources. Looking back on that presentation, because I’ve been accepted to make a very similar one at the Western Water Summit next year, thought it might be interesting to observe how little of that “visioning” has come to pass, how little has changed in the almost 2 decades since then. We seem to remain stuck on the prevailing, essentially 19th century infrastructure model, which is not serving us too well here in the 21st century. And we are seeing the consequences of that in many places and situations, such as around here in the Texas Hill Country, where the infrastructure model is the whole key to avoiding overt degradation of Hill Country waters with “waste” water discharges. Here is the “script” for that presentation, annotated to give context on what was being shown to the audience.

Our water resources infrastructure:

How we got here, why we’ve stayed so long, and where we’re going

Imagine with me that you are a space traveler who has just landed on earth, right here in Austin.  Since you’ve just gotten here, you know nothing of the traditions that have shaped our water resources infrastructure.  You can only see the results.

You look around and see that these earth people are producing most of the water they use to sustain their lives and societal functions about here (presentation showed location of water treatment plant that has since been decommissioned). This water is treated to potable standards, at considerable expense, and that water is transported in a hugely expensive system of pipes to a far-flung service area, such as way up here (presentation showed service area many miles away from that water treatment plant).

Well okay, you say, they’ve got to have water.  But THEN you see through your beady red alien eyes that they use this expensive water—ONCE!!—mostly for uses that do not require fully potable quality water!  Then it is dumped into another hugely expensive system of pipes to be transported way over here (presentation showed location of Austin’s wastewater treatment plant) to another treatment plant that is also very expensive to build and operate, to be partially treated and then dumped back into the river!  And you further observe that the transport system consists of conduits that sometimes leak and overflow, and of pump stations that sometimes fail, and that the treatment plants these earthlings use employ a very “touchy” technology that is very prone to upsets, so poor quality treatment is not an uncommon occurrence.

You also see that, in this particular case, that system of pipes and pump stations is arrayed over a sensitive recharge zone for an aquifer that serves as the source of drinking water to a considerable population.  You hear that in fact one of those pump stations had catastrophically failed not long ago and polluted that aquifer.

You notice that earth people also have the same attitude toward rainwater that falls on areas that could be used to capture it for direct use.  These could be the best, most pure water supplies available.  But considerable investments have been made to flush rainwater “away” in a “hydraulically efficient” manner.

You look at all this and say, “Huh, what WERE these people thinking?!  Why do they treat all this water to irrigate lawns and flush toilets and supply cooling towers and industrial processes – uses that don’t require such highly treated water – at the same time they’re flushing away all this rainwater and once-used water, at considerable fiscal cost and environmental hazard?”

Then you look at the biosolids that result from the treatment process, and you hear that there is a problem with recycling this resource back into the environment because of contaminants that come from certain industrial processes.  You can’t believe they have organized the system to allow that to contaminate the much more voluminous domestic wastewater solids.

You scratch your little green alien head with your little green alien paw and say, “Why do the people put up with this apparent insanity?  How DID they get here?”

It’s that tradition that our space travelers don’t know about.  The following quote from the 1983 World Health Organization book Sanitation and Disease pretty well encapsulates the situation:

“Those whose job is to select and design appropriate systems for the collection and treatment of sewage … must bear in mind that European and North American practices do not represent the zenith of scientific achievement, nor are they the product of a logical and rational process.  Rather, [they] are the product of history, a history that started about 100 years ago when little was known about the fundamental physics and chemistry of the subject and when practically no applicable microbiology had been discovered…. These practices are not especially clever, nor logical, nor completely effective—and it is not necessarily what would be done today if these same countries had the chance to start again.” [Emphasis added]

This quote dwells on the wastewater system, and this is the field of my expertise, so most of what I have to say [in the presentation] is focused on this portion of our water resources infrastructure.  But as I’ve just reviewed, and as our visionaries [other presenters at the conference] have shared with you these last two days, there may be reason to question water supply and stormwater management strategies as well.

As stated in the quote above, the form of the wastewater system infrastructure is largely the product of sanitary engineering tradition.  City populations were exploding, there was extreme squalor developing, and there was a growing awareness of the connection of these conditions to disease.  So the focus was on piping this stuff to that place we call “away”, the universal definition of which seems to be “no longer immediately noticeable by me”.

Only later, as it was seen that the discharge of raw wastes had transformed rivers into foul, open sewers was treatment at the end of the pipe considered.  I’ve read that there was, in fact, a rather intense debate around the beginning of [the 20th] century among water resources engineers whether it would be more “efficient” to treat wastewater before it was discharged, or for downstream users to suffer higher water treatment costs.

Fortunately, today we have a little more respect for other values provided by our lakes, streams and rivers, and treatment of wastewater prior to discharge is almost universally the norm in this country.  However, having recognized the need to do that, it seems we have never gone back and questioned that “pipe it away and dump it” tradition.  Not only do we seem compelled to pipe it away, we want to pipe as much of it to one place as we possibly can.  This centralized system is the largely unquestioned paradigm controlling the development of wastewater system infrastructure.

As our space travelers observed, if you take a hard look at the system of hardware that has developed from this tradition, there are a number of reasons to question why we continue to do things this way.  For one, we’re spending a whole lot of money just to move pollution from place to place.  That system of pipes and lift stations consumes the vast majority of the capital cost of a centralized system.  We’re also concentrating large flows through one pipe or lift station or treatment center, so by the very nature of the system, the consequences of almost any mishap are catastrophic.

Especially since the larger pipes typically run along the lowest terrain available—our riparian environments—we also create significant environmental disturbance when we install, upgrade or maintain the centralized collection system.

And we’re finally coming to realize that the so-called “waste” water is indeed a water resource that we could be utilizing for non-potable purposes to displace a great deal of demand for highly treated potable water.  We’ve found that, once we’ve piped this water “away”, it’s awfully expensive to pipe the recovered resource back to where it can be beneficially  used.

And if we don’t reuse the water, if we just continue to flush it into aquatic environments, the large point source discharges of “allowable pollution” are often problematic, urging the use of ever more expensive advanced treatment processes.

The centralized system also tends to impose a “one size fits all” management system onto a service area, regardless of local characteristics.  The attitude of this traditional paradigm seems to be, if you’re not on “the sewer”, you’re on your own.  So it is not very flexible, and thus not very responsive to land use decisions.

And any upgrades or major extensions of the service area typically entail large-scale projects with long lead times for planning and financing, so the system is also slow to respond to land use decisions.  In a dynamic development environment such as we have here in Central Texas, this can lead to some pretty sorry performance of the management system.

Well, if all these problems are so obvious, if this system is indeed “not especially clever, nor logical”, why have we stayed with this paradigm for so long?  It’s because of the institutional barriers that are arrayed against change.

In my view, the nature of the engineering business is the most problematic institutional barrier.  Billable hours are god.  So it’s really hard to muster much impetus to incorporate new methods and ideas unless the individual engineers go out and learn about these on their own.

That is, unless the firm can talk the client into funding its learning process.  But I’m sure you can see the obvious “image” problem this would create.  The firm has undoubtedly sold itself to the client as the people who can solve its problem, so how would it look if they said, “Hey, there’s some other ideas that ought to be entertained, but we need some hours in our contract to learn about them”?

The result is that most engineering firms are not proficient in anything except business as usual.  I’d venture to guess the percentage of firms that could design, say, effluent sewers or sand filter systems is pretty small.  And even fewer could actually visualize alternative management concepts in which these technologies would fit.  Because of this situation, most firms have a strong vested interest in seeing that their projects focus on the conventional management paradigm.

Added on to this, the sanitary engineering field is, rightfully so, rather conservative.  There are, after all, serious public health and environmental implications at stake here.  But this conservative nature results in any methods and strategies outside the prevailing paradigm, no matter how well justified, being very slow to be embraced.  In what other field, I wonder, is stout defense of the status quo at the expense of vigorously pursuing better and more economical ways of doing the job seen as the best way to maintain and expand your business?

One aspect of that conservatism that has often been used as an excuse for not pursuing alternative strategies is that it’s perceived as difficult to get them permitted through the regulatory agencies.  I don’t believe that’s as much of a problem as it once was.  The so-called alternative methods have been kicked around long enough now that many, if not most, regulatory agencies are at least open-minded about them. [Sadly, in the intervening 2 decades, that has not always been borne out.]

In fact, if there is an expectation that other methods and strategies may result in systems that are less costly, friendlier to the environment, and would have societal benefits, an obvious place from which to stimulate change are the regulatory and funding bureaucracies.  But these institutions tend to concentrate more on process than on substance. Then too, the people in these bureaucracies have been indoctrinated in the same tradition that holds sway among the engineers that submit plans to them.  So these bureaucracies tend to accept those plans without a whole lot of critical questioning about cost and resource efficiency. [As we are now seeing in places like Dripping Springs and Blanco.]

Financing is another significant institutional barrier.  Regardless of the true global costs of various options, institutional arrangements for financing projects are often highly biased toward traditional strategies.  Typically, one who wishes to investigate anything besides “the sewer” is largely on his own and is looking at paying for the ENTIRE management system.  If one hooks up to “the sewer”, on the other hand, the buy-in cost is often a small fraction of the total costs, with the operating entity financing the rest through bonds and grants.

Another significant barrier is the entities that operate the systems.  That’s easy to understand – these guys are immersed in making sure that their existing systems are being operated and maintained properly so they don’t get their butts in a crack.  And basic human nature is also at work here—people are comfortable with the familiar and fear the unknown.  If you go to these people and suggest that they should reorganize their management system and retrain their people to accommodate new methods and strategies – well, that’s not going to make the hit parade with many of them.  At least not without a concerted effort to educate them on how that would be better for the community they serve, and ultimately on down the line for them as well.

And that brings up education.  If education is the key to proliferating better ideas in this field, then perhaps what we have here is a massive failure of the educational system.  It is indeed true that, until fairly recently, engineers who work in this field had not been taught anything but the traditional methods and strategies in their university studies and continuing education courses.  But for many years now, opportunities to learn about other ways to skin this cat have been widely enough available that just about any firm that does a significant amount of wastewater system work could have become expert in other methods and strategies. [That this has not really happened in the intervening 2 decades speaks volumes about how massively the education system has indeed failed.]

And finally, system users are another group that must be addressed.  It can be reasonably argued that the user shouldn’t care how the system hardware is arranged as long as the system is “transparent” to him or her, if all he or she has to do is flush the toilet and pay a fee.  But there is an almost universal fear that proposals to implement “alternative” systems would be rejected by the people that would be served by them.  It seems to come across that any alternative system is “experimental” or a second-class option.  We have a situation right here, in the suburban area of Westlake Hills [which was planning to sewer parts of its jurisdiction at that time], where some citizens are opposed to an effluent sewer system.  Their attitude seems to be fairly well encapsulated by what a lady actually said to me one time when discussing the possibility of a decentralized wastewater system – “Why don’t we just pay more and get a real sewer system?” !!  Also, as long as some funding agency is willing to pony up the lion’s share of the cost, why should the users be particularly interested in assuring that the most cost effective option is implemented?

That’s a lot of reasons to stay “stuck”, isn’t it?  So where do we go from here?

Despite all these barriers to change, a paradigm shift is coming and things are beginning to change, albeit at a snail’s pace. [As we’ve seen in the intervening 2 decades, the pace has indeed been that of a very slow snail.]  I believe that eventually society will come to embrace a “decentralized concept” of management, an idea that I’ve been exploring and discussing since 1985.  That year, in fact, I obtained a permit from the state of Texas for what may have been the very first decentralized concept system ever permitted.  So much for the excuse that you can’t get these things through the regulators, huh?  Unfortunately, that project died in the development bust we had here in 86 and 87.

This decentralized concept will be the antithesis of the conventional, centralized management paradigm.  Under this new paradigm, we will focus on utilization of a resource rather than on disposal of a nuisance.  Rather than look for the most efficient way to make it “go away”, we will look for the most efficient way to reuse the water and the nutrients it contains.  In general, decentralization of the treatment system is the key to achieving this goal.

Decentralization will eliminate a majority of the expense of installing, upgrading and maintaining the far-flung centralized collection system, allowing a far higher percentage of society’s investment to be focused on removal of pollutants rather than on just moving it around, and on reusing these reclaimed water resources.

Decentralization will allow segregation of industrial flows.  Sludge can be classified by source and the biosolid product from “safe” sources will be more easily marketable.  I envision the use of septic tanks or hydroseives located at the source of wastewater generation to be the basic sludge production devices.  While the many dispersed sources of sludge creates a management challenge, timing of sludge handling is not critical with these technologies, and I believe that sludge handling will be less problematic than it is now at centralized plants.

Removal of settleable solids at the source of generation also means that conveyance facilities can be small diameter effluent sewers.  These are less costly to install and maintain, and they practically eliminate infiltration and inflow to the sewer system.  So besides eliminating the cost of interceptor mains and lift stations, the decentralized concept also entails a local collection system that is more economical and eliminates the pervasive problem of high wet weather flows.  Typically, the savings in the local collection system by itself will more than pay for the septic tanks required to allow the use of effluent sewers.

To assure that operations and maintenance of many dispersed treatment facilities is not an untenable problem, treatment technologies will be chosen that are inherently low maintenance.  The small scale of the system will make it cost efficient to design in safeguards against catastrophic failure, and modern remote sensing capabilities will allow the operator to readily monitor the progress of chronic problems.  In short, the treatment system will be far more “fail-safe” than conventional plants, which typically employ the inherently unstable activated sludge technology, and so they won’t need to be placed so far “away” or be watched so continuously.

Some think that newer methods like membrane technology will be the best choice for dispersed treatment systems, and these methods may have a place, but I believe that the workhorse technology of decentralized concept systems will be updated versions of an ancient art – sand filtration.

This technology offers inherent stability, is easy to monitor and control, and, on the rare occasions it’s needed, can be serviced and put back in action in short order.  It’s also capable of producing near-potable quality water, appropriate for a variety of beneficial reuse applications.  Finally, it is a technology that is actually much MORE amenable to use in small-scale treatment centers than in larger plants.

Reuse opportunities that can be entertained without too much institutional resistance are subsurface drip irrigation of any greenspace, surface irrigation of controlled areas, flush water supply to non-residential buildings, and industrial processes that are not highly sensitive to source water quality, or that already employ point of use treatment in any case.  Perhaps after demonstrating that we can indeed control the system and consistently and reliably produce a near-potable quality effluent, we might expand our options to include surface irrigation of uncontrolled areas, flush water supply in residential buildings, cooling tower makeup supply, a wider variety of industrial processes, and perhaps even laundry water supply.

While I see the decentralized concept as where we’re headed, of course we’re not going to abandon the prevailing paradigm and adopt a new one overnight, regardless of how unclever or illogical the prevailing paradigm may seem – society just doesn’t operate like that.  But we do need to begin critically examining our opportunities to move in that direction.

I’ll close with an example of such an opportunity.  There was an article in the local paper a couple weeks ago about the Austin city government’s efforts to direct growth eastward, to what is termed the “Desired Development Zone”.  A problem pointed out by a developer who is planning a project out there is the need to expand and upgrade the city’s water and sewer system in that area in order to handle the growth.  It was reported that this developer needs $10 million worth of infrastructure improvements.

I spoke with [then Assistant City Manager] Toby Futrell after her talk [at the conference] yesterday, and she confirmed that the City is not considering decentralized management as a possibility anywhere in the Desired Development Zone.  Now if we so blindly follow the traditional paradigm, if we simply settle for the status quo, that will be another $10 million invested in piping it “away”.  Another $10 million invested in adding to the problem of long-term regional water supply shortages, another $10 million invested in moving pollution from place to place, in exacerbating point source pollution, and in adding to the biosolids reuse problem.  But in this case we have a somewhat clean slate.  Here there hasn’t been decades of investment in the traditional paradigm that must be respected.  Here we have the opportunity to consider the costs and benefits of building in a new paradigm from the beginning.

This is how we need to start thinking EVERY time a significant investment in our water resources infrastructure system is considered.  The problems are not technological, rather a matter of mustering the political and managerial will to break through the institutional barriers.  We can invest in the past, or we can invest in the future.  The choice is ours.

 

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