The following was originally written for and submitted to the Texas Water Development Board as feedback on how to use the $1 billion Texas Water Fund to “create” some “new” water supply.

Two roads diverged in a wood, and I—

I took the one less traveled by,

And that has made all the difference.

• Robert Frost

In considering the rollout of the Texas Water Fund, it was noticed that the heading of one of the surveys sent out by the Texas Water Development Board seems to indicate there is a bias cooked in for certain sorts of water projects – more on that below. What is offered here is another look at water resources management, one that suggests it will be beneficial to our water economy if we apply and implement a broader vision of how we manage water, and that may make all the difference in just how effectively we can “create” any “new” water supplies. So let’s take a peek down that road not taken … so far.

Regarding that apparent bias, many years ago now a blog post entitled “They’d rather have a root canal …” was published, which noted that the mainstream of the water resources management field was all over actions that could be implemented at the beginning of the pipe – e.g., desalinization – or at the end of the pipe – e.g., direct potable and “purple pipe” reuse – but it seemed they would rather have a root canal than delve into how anything in between the beginning and end of the pipe might be rethought, re-planned, re-engineered, to produce systemically more efficient systems. This missive delves into that and elucidates such opportunities.

It starts with broad systemic thinking, of the sort set forth on the Waterblogue in One More Generation. It is reviewed there how it seems society “thinks” that a “reasonable” strategy is to raid remote aquifers and transport that water, in “California style” long-distance water transfer schemes, to areas which are growing, so presumed to “need” that water supply. It appears that little consideration is being given to the long-term sustainability of the aquifers being raided. As a prominent water professional once observed, our groundwater is being “managed to depletion”. By depleting that water, we would grow a population over the next 50 years or so that (we hope anyway) would not then dry up and blow away, will still be here, still needing water supply for the next 50 years, and so on after that. So it seems this would be a plan to run society into a box canyon, to be just rearranging the deck chairs as the ship goes down, leaving future society high and dry. So it is suggested that we consider how we can “create” some “new”, and renewable, water supply as part and parcel of the development that will serve that growth.

Look! Up in the Sky!

Let’s begin that broad systemic thinking with consideration of building-scale rainwater harvesting (RWH) vs. watershed-scale RWH as the basis of water supply. Of course, since almost all of our conventional water supplies ultimately derive from precipitation, they are all watershed-scale RWH systems, with the watershed being the collection surface, and streams, reservoirs and aquifers serving as the “cisterns”. So first, it should be understood there is nothing “different”, nothing “exotic” about the very idea of building-scale RWH as a water supply strategy. We simply have to consider it more systemically than we have, in the main – a road not taken … so far.

As is reviewed in a piece on the Waterblogue entitled Water for DFW – Building-scale rainwater harvesting vs. Marvin Nichols, the systemic differences in the two approaches to “growing” water supply favors, even highly so, the building-scale strategy. These differences include:

• eliminating transmission losses;
• eliminating the energy cost of long-distance transmission;
• eliminating lake evaporation losses;
• avoiding the environmental and economic disruption and destruction that building reservoirs entails;
• allowing simpler and less costly water treatment for potable supply;
• minimizing or eliminating climate change impacts (oh, wait, we can’t talk about that in Texas, sorry);
• water savings due to it taking less energy to deliver the water supply – the so-called water-energy nexus;
• lower impact on environmental flows;
• matching up the timing of costs to implement supply more closely with imminent need for supply, the so-called “time value of money”, understanding that under the watershed-scale RWH strategy, a whole lot of investment must be put in the ground before water supply can be provided to the first house or business, while under the building-scale RWH strategy, the supply for each building is installed on a “just in time” basis; and
• because of this, there would be a much lower investment put at risk.

It is noted in passing that some folks are touting transmission line loss control as the epicenter of how we can “create” some “new” water supply, by better husbanding the water we already have. While of course any and all conservation efforts must be a necessary component of this whole effort, it is observed that this simply highlights the flawed nature of the watershed-scale RWH water supply strategy. Even with the very best loss control deemed feasible, there would still be considerable transmission losses. Maybe “good enough” as long as water supply doesn’t get too tight, but maybe too big a chunk out of supply when it is tight. So it is asserted that a better way to blunt those losses would be an infrastructure model that would pretty much completely obviate line losses, the building-scale RWH strategy.

Yet, we have seen no meaningful consideration of building-scale RWH as a broad scale water supply strategy. To the extent it is considered as a strategy at all, that is sequestered to individual building owners, evaluated in a micro-economic climate that does not take into consideration any of these systemic advantages; the long-run economic analysis is pretty universally ignored. So it is asserted that this is an arena ripe for investigation, with the potential for yielding huge amounts of “new” supply over much of the state in a globally cost efficient and resource efficient manner. The Texas Water Fund should direct resources toward broad proliferation of building-scale RWH.

Waste Not, Want Not

The other major arena in which better systemic thinking is needed is wastewater reclamation and reuse. As noted, there is a mainstream bias for understanding reuse pretty much exclusively as something that would be appended on to the system at the end of the pipe, really as if it is just an afterthought rather than a central function. It is suggested that this whole paradigm be rethought, that we focus on designing reuse right into the very fabric of development, as if it indeed were a central function of this societal process we call wastewater management.

To do this would entail reconfiguring the wastewater system architecture, so that this water resource would be treated, and reused to the maximum extent feasible, as close to where this water is “generated” as practical. Of course the rub here is “as practical”. The mainstreamer “understanding”, even codified in TCEQ rule, is that wastewater is “best” managed on a “regional” basis, urging the routing of flows from as far and wide “as practical” to one point source.

That reconfiguration of wastewater system architecture was labeled the “decentralized concept” of wastewater management back in 1986, set forth as an alternative organizing paradigm for a wastewater system of any overall scale. All that was based on works prior to that, so really there is nothing “new” about the decentralized concept strategy; it too is just a road not taken … so far.

As has been reviewed in many works, the “regional” system is really just the product of 19^th century tradition, when, with the stuff running in the streets, the whole focus was on piping it “away”. That tradition has simply been “extended”, with no thought on whether that would be the best manner of managing this societal function in the dynamic development market, and with the water supply challenges, we have in Texas today. It is high time that society engages in that rethinking and considers the systemic efficiency of distributed vs. “regional” systems.

A look at just how the decentralized concept could be implemented in a hinterlands development in the Hill Country is set forth on the Waterblogue in This is how we do it. A comparison of this strategy vs. piping such a development into a “regional” system is offered in Let’s Compare. As these works review, using the decentralized concept strategy in lieu of the conventional “regional” strategy can deliver fiscal, societal and environment advantages.

In the fiscal arena, we can realize several advantages:

• With the treatment units being distributed to the “neighborhood” scale, all of the large-scale collection system infrastructure, trunk mains and lift stations, would be obviated. As the collection system is typically a large majority of total “regional” wastewater system cost, this would impart a huge cost savings.
• For any local collection system that is needed, the effluent sewerage concept would be favored, rendering those lines more cost efficient, as reviewed on the Waterblogue.
• Little to no infiltration/inflow would plague the effluent sewerage collection systems, decreasing maintenance costs and peaking loads on treatment units, allowing some components to be downsized.
• Using effluent sewerage renders the sludge management function more cost efficient, and otherwise less burdensome.
• With treatment units distributed, the reclaimed water redistribution system would also be smaller scale, thus far less costly than “purple pipe” systems redistributing water from “regional” plants, so rendering reuse more affordable, thus more fiscally feasible, delivering cost – and sustainability –  benefits by displacing demands on the potable water system.
• The distributed system architecture would also typically obviate pumps (lift stations) in the collection system, so saving all that energy, saving money.
• The type of treatment unit we need to employ in the distributed treatment units – the High Performance Biofiltration Concept (recirculating packed-bed filter) unit is highly favored, as reviewed in This is how we do it – would incur fairly minimal routine O&M cost.
• The High Performance Biofiltration Concept treatment unit would require a lot less energy to operate than an activated sludge system, practically the knee-jerk choice by the mainstreamers, so saving a lot of money.

Societal implications would be significant. More fully reviewed in Let’s Compare, those implications are listed here:

• As noted above, reuse of effluent would become more cost efficient.  The effluent would be made available throughout the service area, nearer to points of potential reuse, greatly decreasing the cost of the reclaimed water distribution system.  Non-potable demands such as landscape irrigation, toilet flush supply, and cooling tower makeup could be more expeditiously and cost efficiently served with reclaimed water, spurring on this action, so defraying demands on the our increasingly stressed water supplies.
• Requiring far less energy for treatment and to move water around, this distributed treatment and reuse would also reduce greenhouse gas emissions (oh, sorry again to mention climate change, but this IS a societal advantage).
• The management system would be able to accommodate any level of water conservation found to be economically attractive or ecologically necessary.  Only liquid effluent is transported, so reduced wastewater flows due to water conservation measures would not cause clogging problems in the collection system, as has occurred in conventional centralized systems.
• The decentralized concept system is easier to plan and finance.  Each project is small compared to the typical “regional” system expansion.  The management needs of each area or new development are considered directly and could be implemented independently. Contrast this with planning large-scale facilities over an area-wide system, with much less definite growth prospects in any given area.
• Capacity expansion – and therefore capital requirements – would track demand much more closely, minimizing the amount of money spent to construct facilities which would not be fully utilized for years to come, as occurs routinely in the course of expanding and upgrading conventional centralized systems. Again, the “time value of money”.
• Much of the cost could be privatized or assigned directly to the activity generating new demands on a much fairer basis, so that existing ratepayers and/or taxpayers would not have to serve as the “bank” for this infrastructure, which is typically the case as upgrades and expansions of the conventional centralized system are bond financed by public agents.
• This is all money “at risk”. If, for example, we were to experience another “crash” such as occurred in 2008, the pace of development might slow, even stop altogether for a time. But once the money is borrowed and the system built, the payments would be due whether development came on line to fund those payments or not. So whoever financed that infrastructure would be on the hook to make those payments. If these facilities were publicly financed, it would be all of the ratepayers, and/or taxpayers, who would be called upon to pony up. This could balloon their wastewater rates and/or tax bills. All that would be avoided under a decentralized concept strategy, which assigns that risk to the developer, who would be putting relatively small amounts at risk at a time.
• With the hardware systems decentralized, there would be no compelling reason to impose a “one size fits all” management approach.  Different strategies could be employed in various parts of the service area, responding in the most fiscally efficient and environmentally responsible manner to each set of circumstances – e.g., on-site systems in low density development, distributed systems on the urban fringe and in the hinterlands, connection to a centralized system where that might be the cost efficient strategy – with all those systems under one unified management system.
• The system can be designed and installed in a manner which is “growth-neutral”, whereas centralized systems often spur growth, even requiring it to be fiscally viable in many cases.
• Distributed management reduces vulnerability to pollution.

This leads us to considering the environmental advantages of the decentralized concept strategy, which include:

• Scale is a major driver of environmental vulnerability. Centralization causes large flows to be concentrated through one pipe or lift station or treatment plant.  This implies that any mishap would have large consequences.  In a decentralized concept system, the flows at any point remain small, implying less environmental damage from any mishap.
• In a distributed system, any mishap that may occur would impact on only a minor portion of the overall system, as each distributed system is disconnected from all the others, so imparting far less overall vulnerability.
• In any case, bypasses, leaks, overflows, etc., would be far less likely in a decentralized concept system. More “fail-safe” treatment technologies would be employed, and lift stations would be eliminated or greatly reduced in number.  Carrying only liquid effluent to multiple treatment centers, the effluent sewer collection system would consist of shorter runs of smaller pipes containing fewer openings, implying far less potential for infiltration and exfiltration and for overflows.
• There would be less environmental disturbance from system construction.  The smaller effluent sewer collection system pipes would be installed at shallow depths and could be more flexibly routed.  There would be no large interceptor mains, which typically run in riparian areas, requiring these riparian environments to be disturbed to install the mains.
• Environmental disturbance would be minimized over the long term as well because existing lines would not need to be torn up to upgrade system capacity.  System expansion would be afforded by adding a new treatment center for each newly developing area rather than by routing ever more flow to existing centers.
• Treatment and reuse can be “tailored” to the waste stream.  Industrial waste need not be commingled with domestic wastes; rather these generators can be required to implement treatment methods specific to their wastewater characteristics and reuse opportunities.

While all these fiscal, societal and environmental advantages should be creating high incentive to consider organizing wastewater systems in accord with the decentralized concept, most important here is the ability to more cost efficiently route the reclaimed water to beneficial reuse, so spurring on that practice, thereby defraying demands on our increasingly stressed water supplies. In regard to the Texas Water Fund, that of course is the main reason to move management in that direction. Again by designing reuse into the very fabric of development, this can “create” a “new” water supply in a far more fiscally efficient manner than can generally be done under the conventional “regional” system paradigm. So the Texas Water Fund should direct resources toward proliferation of reuse-focused decentralized concept “waste” water systems.

Don’t Drain It, Retain It

Before proceeding, it is noted in passing that sustainable water can be enhanced by moving storm water management practice to distributed Low-Impact Development (LID) strategies, for example as outlined on the Waterblogue in … and Stormwater Too. Rather than draining “away” the increased runoff created by development, it should be retained and infiltrated, so as not to desertify the landscape as it is developed. Some of that increased runoff could be captured and directly used for water supply. As reviewed on the Waterblogue, rainwater harvesting for irrigation supply – and in settings where those uses come into play, for toilet flushwater supply and cooling tower makeup supply too – can readily be integrated with the storm water quality control function.

Really, this is a subset of the building-scale RWH strategy. Attention specifically to this is merited, however, as there is a considerable market for this practice, in both new development and in retrofit projects. So this is a road now being partially trod, but the journey lacks much institutional support; it is largely driven by individuals considering their immediate needs. Thus in regard to how society is proceeding to consider how we “create” any “new” water supplies, this too is a road not taken … so far. The Texas Water Fund should direct resources toward expanding these storm water management practices.

Examples of the Opportunities

To illustrate the currency of these manners of “creating” any “new” water supplies, let’s look at some examples.

The first example is a small-bore project, but one that if repeated over and over could add up to a whole lot of “new” water supply. It is a hinterlands project in the Hill Country, called Lunaroya, proposing 28 lots with areas between about 1.5 and 2.5 acres each, located on Barton Creek. The conventional plan for water supply would entail a public water supply well, storage tank and distribution system, all of which would have to be planned, designed and permitted “up front” as a Public Water Supply System (PWSS). It was reported that the water quality out of the well would be such that reverse osmosis (R.O.) treatment would be needed to render the water to potable quality, and this treatment would result in something like 70% of the water supplied from the well becoming R.O. “reject” water, a brine toxic to plants, and so there would have to be a “disposal” system for that water created as well.

It is suggested that all this waste could be obviated by using building-scale RWH for water supply to the houses in Lunaroya. In this area, these acreage lots will be rather expensive, so it is to be expected that houses built there would be “large”, with the roofprint area needed to make RWH systems highly sustainable being installed as a matter of course, between the house, the garage, and covered porches and patios. This leaves the cistern and the rainwater treatment unit – a simple cartridge system and UV disinfection unit – as “extra” costs for an RWH system at each house.

By going with building-scale RWH, not only is the high level of water waste out of the well obviated, but so are the costs of the well, the storage tank, the distribution system, the brine disposal system, and all the planning, design, and permitting costs of those components. This would save the developer a very large sum in up front costs that would need to be paid before water service could be provided to the first house in Lunaroya. This savings could translate to lower lot prices, so defraying the cost of the cistern. Since the RWH systems for each house would be planned, designed and implemented by the owner/builder of each house, all the developer would need to pay up front for water supply would be for the planning items specified by the county as part of the platting process in subdivisions proposing building-scale RWH as the water supply strategy, a very minor fraction of all those up front costs for the conventional water supply system.

As for marketability of houses that use building-scale RWH for water supply, there are hundreds of houses using this supply strategy in the general area where Lunaroya is located. So it is a well known commodity, which can readily be financed by lenders. With a bit of education, some modeling to show how sustainable this supply can be made, this strategy should readily be rendered “non-scary” to any potential buyers of lots in Lunaroya. It is also reputed that rainwater is a superior water supply, being naturally soft, so gentle on skin, clothes and fixtures, that people who use it love it. So the developer would have no reason to fear the lots could not be marketed.

For “waste” water management, it was proposed to use On-Site Sewage Facilities (OSSFs), more popularly called “septic systems”. In particular, it was asserted that a spray field be sited on each lot to “dispose” of this “waste” water, after pretreatment in a home-sized bastardized version of the activated sludge process, commonly called an ATU – “aerobic treatment unit”. So really it is proposed that 100% of the water to be drawn from the well would be wasted, about 70% directly as R.O. reject water and the other 30% or so being “disposed of” – thrown away – after being used once in the house.

It is suggested that the OSSFs be recast as reclamation and reuse systems. Each one would be composed of a High Performance Biofiltration Concept treatment unit, which would remove the majority of the nitrogen from the “waste” water – important in the Barton Creek watershed – feeding the effluent into a subsurface drip irrigation field, arrayed as much as practical to irrigate landscaping that would be irrigated in any case. This type of OSSF has been designed, permitted and installed in several jurisdictions in Texas for almost 30 years now, so is a well known, well understood type of “septic system”.

By this means, a large majority of the “waste” water generated in the house over the annual cycle would be beneficially reused for irrigation, so greatly defraying demands on the potable water supply to the house. For the owners of houses in Lunaroya, defraying irrigation demand would allow them to downsize their RWH systems – the roofprint area and cistern volume – while still maintaining high sustainability of that water supply and maintaining some irrigated landscaping.

The cost of implementing this form of OSSF would not be all that much more than what the ATU-spray system would cost. Especially since the drip irrigation field would in some part displace an irrigation system that would be installed in any case, if the homeowner intended to maintain any irrigated landscaping.

Thus it’s apparent that the alternative scheme, a set of “One Water” strategies, would save a whole lot of water. 37 acre-feet per year is being requested to be permitted by the governing groundwater district. This calculates out to be an average demand of 1,180 gallons/day per house. Note again, only about 30% of that flow, or about 350 gallons/day per house, would be a usable water supply; the rest would become R.O. reject water, an utter waste of this water, greatly downgraded in quality by the R.O. treatment, and so posing an expense for proper “disposal”. Going with building-scale RWH instead, society would save all that water, the developer would immediately save a large sum for all those obviated up front costs of implementing the PWSS, and the residents would enjoy the superior quality of the rainwater supply. This is a win-win-win, for the developer, for the homeowner, for the water environment. It is the sort of action that the Texas Water Fund should have some mechanism for fostering.

The next example is the Mirasol Springs project, presently in the planning and permitting stage, along the Pedernales River near where it is crossed by Hamilton Pool Road. The development comprises an Inn, restaurants, some large “conservation” lots, some “branded residential” houses, “resort cottages”, an event barn, a University of Texas field research station, and a farm. The situation is described on the Waterblogue in If you’re going to call it a vision …, reviewing how the developer is presuming to call a very conventional set of water resources management practices a “new standard for environmentally focused Hill Country development”. It is suggested that an actual “new standard” would be a “total One Water” scheme, essentially following the water supply, wastewater management, and storm water management concepts set forth above. The basics of this program would include:

• All the houses on the “conservation” lots, arrayed on both sides of the environmentally sensitive Roy Creek Canyon, shall have water supply provided by building-scale RWH.
• All the houses on the “conservation” lots shall have wastewater service provided by OSSFs, using nitrogen-reducing recirculating packed-bed filter (High Performance Biofiltration Concept) treatment units and dispersing the reclaimed water in subsurface drip irrigation fields, arrayed to the maximum extent attainable to irrigate the highest value landscaping on the lot, landscaping that would likely be irrigated in any case, to minimize need for harvested rainwater for irrigation.
• Together, these strategies will obviate all water and wastewater lines running through/across Roy Creek Canyon, eliminating that source of water quality degradation and saving the developer the budget of a small African nation in upfront costs that would deliver a very limited amount of service.
• All the developer would have to do to market those lots is plat them and provide road access. Paying for and installing the RWH systems and the OSSFs would fall to the owners/builders on each lot.
• Savings on the obviated water and wastewater lines would be far more than the cost of a tanker truck, which the manager of the overall water supply system could use to provide any backup supply to the houses, if ever needed, to provide high assurance of backup water supply at need to these homeowners. In the meantime, with it being needed only rarely, that truck could be leased out or used for other needs, to defray its cost.
• This same strategy may be applied to the “branded residential” houses, similarly eliminating up front costs for the developer, obviating water distribution line runs and wastewater collection and reuse redistribution lines, and their costs and environmental liabilities. Also reducing the capacity needed in the surface water and/or groundwater supply and wastewater management systems, so reducing those costs, which the developer will have to pay up front.
• This same strategy may also be readily applied over the “resort cottages”, where all units are likely to be on a single lot under single ownership, so a collective RWH system and a collective OSSF would be readily doable, institutionally as well as technically. Again, saving on water distribution lines and wastewater collection and redistribution lines, and eliminating their environmental liabilities. And further reducing the capacity needed in the surface water and/or groundwater supply and in the wastewater management system. Noting that due to the nature of this service, this RWH system may have to be permitted as a PWSS, but that is readily doable, and that PWSS could very readily be operated by the entity established to run the overall water supply system.
• Building-scale RWH for water supply and an OSSF for wastewater management could also service the research center. In particular as it appears this facility would be “off to the side” at some distance from other facilities, this would save on water distribution lines and wastewater collection and redistribution lines, and again reduce the capacity needed in the surface water and/or groundwater supply and the wastewater management system. All of these costs could likely be shunted off to the entity that develops and builds the research center facilities, so here too reducing the developer’s up front costs.
• It appears practical to use building-scale RWH for water supply and an OSSF for wastewater management for the event barn. Again, savings on water and wastewater lines, savings in water supply capacity, and elimination of environmental liabilities that wastewater lines would entail.
• This leaves “only” the Inn and the restaurants to be provided water supply from surface water and/or groundwater. Even for those facilities, however, rainwater supply off those roofs can defray water demands. Here again, even if the RWH system would need to be permitted as a PWSS.
• Consider using slow sand filter for the surface water treatment process, a system very well suited to treating river water. Likely less expensive to build – could readily be phased as needed, installing multiple beds – and far less expensive to operate and maintain than the conventional water treatment plant that the developer is proposing.
• The Inn and restaurants would have design flow rates above 5,000 gpd, so the wastewater system(s) to serve those facilities would have to be permitted at TCEQ under the “municipal” permitting process. But the form of such systems could be the same as the OSSFs, using the highly stable and robust nitrogen-reducing recirculating packed-bed filter (High Performance Biofiltration Concept) treatment unit – rather than the inherently unstable, high operating cost activated sludge unit, which would need cost increasing modifications to attain significant nitrogen reduction – and dispersing the reclaimed water as much as practical to irrigate grounds beautification. Understanding that the subsurface drip irrigation fields to irrigate that landscaping would be in effect the “TLAP” fields for this system. Installing drip fields in the “waste meadows” could be largely, if not completely, obviated. All of this will also decrease the developer’s up front costs.
• The “farm” is a wild card, but it is quite likely that everything but crop irrigation (but maybe some of that too) could have water supply provided by building-scale RWH and all wastewater generated there could be managed in an OSSF. It may be that some of the drip irrigation field receiving reclaimed water from the Inn and restaurants could be on the farm, irrigating some of the crops.
• There should also be discussion of the form of storm water management facilities. Note that a very robust program of rainwater harvesting will basically take rooftops “out of play” in regard to storm water quality management, and reduce the scale of water quantity management (detention) facilities. Maximizing use of permeable pavement would also reduce need for water quality management installations. All this too is quite likely to reduce the developer’s up front costs.

The developer has applied to use surface water from the Pedernales River and groundwater from the local aquifer to provide water supply for this project. The adoption of this “total One Water” set of strategies would obviate a large portion of those draws on these sources, each of which is understood to be rather limited. Indeed, it is the expectation that both surface water and groundwater supplies might be curtailed during future droughts that motivated the developer to apply for access to both supply sources.

Given the clear opportunity to render the water resources management infrastructure more fiscally efficient, including the “time value of money” benefit of being able to defer installation of infrastructure until the building it serves would be built – noting this project has a projected 10-year timeline to completion – and higher quality of rainwater supply, the “total One Water” set of strategies presents a win-win-win prospect for the developer, for society, and for the eventual users/residents of this project. That it appears this sort of approach is currently being ignored by the developer illustrates the need for the Texas Water Fund to include some means of promoting, maybe even incentivizing, the move toward sustainable water practices, so as to proliferate them throughout the development community.

Those two examples are out in the hinterlands, so not entailing how to apply these concepts within the context of a community-scale utility system. For that, we look first at the situation facing the City of Liberty Hill. The city has applied to TCEQ for a permit to increase the capacity of its wastewater system from 2 Mgd to 4 Mgd. This shows that a lot of the future flows would derive from new development, and that would be mainly located on the urban fringe and in the surrounding hinterlands. Which in turn suggests that, for all the reasons reviewed above, the city might consider moving to a decentralized concept strategy to serve that growth, rather than to expand the capacity of its centralized point source treatment plant and extend sewers ever further into the hinterlands.

This strategy may be doubly beneficial to Liberty Hill because the new permit carries with it a more stringent restriction on phosphorus concentrations in the effluent to be discharged into the South San Gabriel River. This was imposed because the current discharge has stimulated massive algal blooms in the river, contended to be a violation of the Clean Water Act. So, while the city would have to take measures to reduce effluent phosphorus concentration in the existing flow, they can save money by not having to increase the capacity of the phosphorus removal process(es) for the additional 2 Mgd of flow. Particularly since none of that flow currently exists, so the investment required for increasing the central point source treatment plant capacity would be money that would not be fully utilized for many years into the future. The “time value of money” thing again.

It was communicated to the Liberty Hill mayor and city council members how they could go about moving to a decentralized concept strategy to serve new development in and around the city. And perhaps to even “unhook” some existing development, using the “sewer mining” strategy. Then perhaps to also install a “purple pipe” system from the central point source treatment plant to minimize the amount of water that would need to be discharged into the river. By these means, they could reduce the considerable investment needed for phosphorus removal processes.

As argued above, it is to be expected that by going with the decentralized concept strategy to serve new development, the city could expand its wastewater system capacity at lower cost, and – again the major point here – would put a lot of that wastewater to work for society, beneficially reusing it to defray demands on the area’s water supply sources. Blunting any future “need” to import water from remote aquifers, and all its attendant inefficiencies, and apparent unsustainability, as was reviewed above.

What is not addressed in those communications is that there would also be opportunities to make building-scale RWH part and parcel of the water supplies for the new development. Together with the “new” water supply “created” by reusing rather than discharging the flows from all these sources, there is a win-win-win to be had here, for the city’s ratepayers/taxpayers, for the developers, and for society by moving practice toward sustainable water. Again highlighting how the Texas Water Fund needs to create some means of promoting, perhaps incentivizing, the move to sustainable water practice, at all scales.

The last example offered is the “Zero Net Water” concept that had been posed a decade ago, proposing to maximize building-scale RWH, condensate capture, and building-scale/campus scale wastewater reuse to provide water supplies, an exponent of the strategies reviewed above. One example of this has been set out by Texas Water Trade (TWT) just recently as part of its Strategic Plan, which they have labeled as “Net Zero Water”. As TWT styles it, this concept – which is well set forth in its Net Zero Water Toolkit – is largely envisioned to be mainly applied in “big box” projects, like large institutional or commercial buildings. But of course as reviewed above it could also be applied in many sorts of developments, at various scales.

The explicit opportunity to cost efficiently expand the Zero Net Water strategy to smaller projects, explicitly in regard to wastewater reuse, is reviewed on the Waterblogue in Appropriate Technology. This hinges on moving to technologies better suited to distributed deployment, rather than simply scaling down the conventional technologies used at large centralized treatment plants.

However it is done, going with the Zero Net Water strategy would “create” considerable “new” water supply, through building-scale RWH, condensate capture, and distributed wastewater reuse. While market forces are already moving this strategy forward – and as noted it could be cost efficiently extended into markets that appear to be not currently recognized – this is another arena in which the Texas Water Fund could promote and incentivize that move, relieving stress on the watershed-scale RWH systems, saving a whole lot of water for society.

Stimulating Action

While the arguments for moving water resources management practices toward sustainable water are solid, compelling even, it is clear that the mainstream “thinking” in this field does not, in the main, recognize those practices. Thus there is little if any such change in practice showing up in regional water plans, and so in the State Water Plan. Evidencing, as is suggested throughout this document, that measures to proliferate the vision, knowledge and skills required to put these sustainable water practices on the ground need to be stimulated and pursued.

It is suggested that, in terms of the programmatic/bureaucratic activities that create the regional water plans, there needs to be a more inviting forum, that would encourage the pursuit of the sorts of sustainable water practices as have been highlighted herein. Attendance at a regional planning group meeting has been an experience of sitting through mind-numbingly programmatic/bureaucratic discussions and machinations, with such ideas as basing broad scale water supply strategy on building-scale RWH or the decentralized concept of wastewater management never even coming up for discussion. Much less is there any consideration of incorporating any of that into the regional plan. Rather, everything is focused on extending and perpetuating practices that constitute business as usual in the water resources planning and engineering field. Indeed on such actions as desalinization at the beginning of the pipe or direct potable and “purple pipe” reuse at the end of the pipe, neglecting how we can rethink, re-plan and re-engineer anything in between. It seems they would rather have a root canal …

Because of this groupthink being “expected”, it remains quite difficult to gain any traction in getting those who would implement water resources management infrastructure – municipalities, utilities, developers, etc. – to even entertain a peek down the road not taken. So there is much work to be done.

We began this missive with the closing lines of a Robert Frost poem. Let’s end it with some more poetry, these song lyrics by Neal Peart of the band Rush, from “Vital Signs”:

Leave out the fiction
The fact is this friction
Will only be worn by persistence

Leave out conditions
Courageous convictions
Will drag the dream into existence

So who is going to apply the persistence, who will impart the courageous convictions, who is going to drag the dream into existence? Who will lead in taking a peek down the road not taken … so far? If Texas is to avoid a dark water future, perhaps becoming unable to accommodate more growth, or even to maintain beyond one more generation the currently occurring population growth, that is being bought by “managing to depletion” existing water supplies, it must consider how to move practice toward sustainable water. And that could make all the difference.

I am part of a group that is putting together a course, perhaps to be offered by Texas A&M, to teach the “One Water” concept, culminating with a “certificate” that is expected to have some meaning for practice in this arena. The major activity in the first gathering of that group was to set forth ideas on what the course content should cover. As a “conversation starter” I offered the group a rundown on what the “components” of a “One Water” scheme might include. A major theme of that document was that “One Water” schemes would be basically “distributed” concepts. Let’s explore that whole idea.

A working definition of “One Water” is offered by the Meadows Center for Water and the Environment at Texas State University as:

“One Water is an intentionally integrated approach to water that promotes the management of all water – drinking water, wastewater, stormwater, greywater – as a single resource.” [emphasis added]

This definition can be illustrated in practice by these examples:

• Wastewater and water supply can be integrated by designing and developing the “waste” water system to focus effort and resources on producing a reclaimed water supply, preferably close to the point of reuse, which would be utilized to defray demands on the “original” water supply to the project.
• Stormwater management and water supply can be integrated by capturing the additional runoff caused by development, in cisterns and/or landforms, rather than allowing it to “efficiently” drain “away”, with the captured water used as explicit water supply – e.g., building-scale rainwater harvesting, using water captured from roof runoff into cisterns to defray, or displace, demands on the “original” water supply – or to enhance the hydrologic integrity of the site by maintaining the rainfall-runoff characteristics of the “native” site on the developed site, holding water on the land instead of “desertifying” the land by draining “away” water that would have otherwise infiltrated to maintain deep soil moisture, to recharge aquifers, etc.

These examples highlight a fundamental imperative of “One Water” practice – to maximize the sustainability of water supplies, these integrated management strategies must focus on addressing all water as a resource to be husbanded, not as a “nuisance” to be gotten rid of, to be wasted as expeditiously as possible, which has been the focus of conventional stormwater and wastewater management practice. Of course, the water does not actually “go away” – the hydrologic cycle is a closed system on a global scale – but those practices are wasteful in that they expend resources to route the water out of, rather than to maximize its beneficial use within, the immediate environs. Each gallon that is so externalized (wasted) is another gallon that must be imported into the project, and (in this region particularly), all existing water supplies are becoming increasingly strained.

A basic principle, highlighted for example by Paul Brown of CDM – a voice from the very heart of the mainstream – in his preface to Cities of the Future, is that water is most sustainably managed by maximizing the beneficial use of these resources within the project, as much as practical, “tightening up” the loops of the hydrologic cycle, rather than externalizing those resources and then importing water from “traditional” supplies to make up for these externalized – wasted – resources. By following this “One Water” practice, the developer, the eventual users of the project, and the community-at-large will realize fiscal, societal, and environmental benefits.

A simple schematic comparing a non-integrated – or “silo’d” – system with an integrated management system is shown in the figures below, illustrating how husbanding of the water resource may be enhanced by this “tightening” of the water loops. As this illustrates, the same overall function might be obtained while imparting about one-half the draw on the “original” water supply to a project.

As this illustrates, the “One Water” methods would integrate into the land plan, rather than being appended on, divorced from the land plan, as is typical under the “silo’d” conventional management strategies. In short, water resources sustainability would be designed into the very fabric of each project. And thus, we see that “One Water” would typically be most effectively accomplished by decentralizing the water resources management infrastructure.

Before proceeding, it is important to acknowledge that context is important, and in each circumstance, the full range of available options should always be evaluated, including both “centralized” and “decentralized” schemes. So while it is presented here that distributed infrastructure seems typically more likely to produce the better “One Water” schemes, there will of course be instances in which a more conventional looking “centralized” infrastructure would prove to be the “better” option. For example, in an area with the conventional centralized “waste” water system architecture already in place, the “best” option for assuring that “waste” water realizes its resource value may be the installation of a “purple pipe” system to redistribute water from the centralized treatment plant to points of reuse.

Moving on … While as noted the intention should always be to integrate the various water management functions, in practice each of them – water supply, “waste” water management, and storm water management – are typically addressed individually, with the “integrations” generally falling out of the means and methods that are utilized. Referring to the examples listed above, water supply and “waste” water management could be integrated by utilizing the “waste” water resource to defray demands on the “original” water supply source for the project being served by that “waste” water system. Note that the water supply system itself would not be “perturbed” by this scheme, it’s just that part of the supply would now be shunted off to the “waste” water being reused to create that adjunct supply.

Generally, as also noted above, that integration, the defraying of water supply demand, would be maximized by designing that whole process into the very fabric of the development. Which brings us to the “decentralized concept” of “waste” water management.

Noting that the “One Water” concept generally entails “tightening” the water loops, integrating water management into the very fabric of development, it becomes rather obvious that “waste” water systems would be “distributed”, rather than “regionalized”, as is the mantra of much of conventional practice. The “decentralized concept of ‘waste’ water management” – set forth quite consistently by the author over the last 37 years – embodies this whole idea. This is an alternative organizing paradigm for a “waste” water system of any overall scale. Here is the basic idea, as set forth in a 1988 paper by the author:

“Stated simply, the decentralized concept holds that ‘waste’ water should be treated—and the effluent reused, if possible—as close to its source of generation as practical. In particular, it is suggested that the first stage of treatment—for which a septic tank is preferred, as outlined later—be placed at or very near to the ‘waste’ water source, regardless of how centralized the rest of the system is. The conventional “on-site” system might be viewed as the ultimate embodiment of this concept, and on-site systems might indeed be the appropriate technology for parts of the service area. In areas where soil and/or site conditions dictate that conventional on-site systems would not be environmentally sound, the septic tank effluent might be routed through further treatment processes before dispersal or reuse.

“However, the concept is very “elastic”.  In practice, it may be beneficial to aggregate several waste generators into one septic tank or to route septic tank effluent from several generators into a collective treatment and dispersal system.  The most appropriate level of aggregation at any stage of treatment would be determined by a number of considerations, such as topography, development density, type of land use, points of potential reuse, or locations where discharge is allowable.

“Judicious choice of technology at each stage of the collection and treatment system can help advance fiscal, societal and environmental goals.”

Note in particular three items in that description:

1. The term “waste” is in quotes to highlight that “wastewater” is a complete misnomer for designating what, within a “One Water” concept, must be addressed as a water resource to the maximum extent practical in each circumstance.
2. The over-arching aim of “wastewater” management is not “disposal” – as basically defines conventional practice – rather must be focused on producing a reclaimed water, to be used to defray demands on the “original” water supply to the project being served by the “waste” water system, to the maximum practical extent in the circumstances at hand.
3. With the overall system distributed, practical operation of multiple distributed treatment units demands that “judicious choice” of technologies to be used to assemble the system.

This all leads to identifying the basic “tools” of the decentralized concept, as has been set forth by the author and others in any number of works in this field, those tools being:

• Effluent sewerage is highly favored for any collection of “waste” water beyond the building site level. This is the concept of intercepting flows at, or very near to, the site of their generation in septic tanks – termed “interceptor tanks” within the effluent sewerage concept because they intercept the “big chunks”, leaving only liquid effluent with very low levels of settleable solids to be transported any further, so allowing the use of effluent sewers, instead of conventional “big pipe” sewers. This reduces the cost of the “remant” collection system that remains in the distributed system and minimizes the environmental impacts of the collection system, practically eliminating leaks, bypasses and overflows, not to mention minimizing the degree of disruption entailed in installing the smaller, shallower effluent sewer collection lines.
• Treatment beyond the septic tank must be done with “fail-safe” technologies. The term “fail-safe” is in quotes because any sort of treatment unit must be properly operated and maintained so as to continuously and reliably produce the expected effluent quality, but certain technologies, by dint of their very nature, are more robust and “forgiving”, and so can stay “on track” with rather minimal O&M effort and attention. This is essential to creating a management system that would not become overtaxed by needing to police the multiple treatment centers that following the decentralized concept would create. What types of treatment units that fall into the “fail-safe” category, and how to design those units will likely be a matter of opinion in this field. It is the author’s long-held view that inherently stable technologies like the recirculating packed-bed filter and constructed wetlands be highly preferred in lieu of the activated sludge process that is practically the “knee-jerk” choice in conventional practice. This is because the activated sludge technology is inherently unstable, an effect that becomes more problematic in “smaller” treatment plants, really anything but the treatment plant being “based loaded”, as is extant only in large “regional” treatment plants.
• Again, the fate of the effluent, the reclaimed water, is to serve water uses that would need to be met whether or not the effluent were available for that usage, and to properly apply the reclaimed water to serve those demands, and so defray demands on the “original” water supply source. It is to be expected that irrigation is likely the most “available” and readily served use in many cases. In particular in climates such as exist in this region, for which subsurface drip irrigation – itself a “fail-safe” technology of sorts – should be preferred, to maximize irrigation efficiency – also of course a basic “One Water” principle” – and to sequester the reclaimed water underground to minimize potential for human contact in the highly distributed reuse sites. Other uses may include toilet flushwater supply, cooling tower blowdown makeup, and perhaps even laundry water supply.

An example of how these tools could be employed to create a decentralized concept system strategy was reviewed in “This is how we do it”, showing the benefits, in particular to practically maximize the resource value of the “waste” water, of the decentralized concept scheme vs. a conventional development-scale system or a conventional centralized system.

Thus we see that in terms of “waste” water management, “One Water” basically equals the “decentralized concept” of “waste” water management. This strategy focuses investments on properly treating and effectively reusing the water resource, rather than on just moving the stuff around – which is all the far-flung collection system within the conventional centralized system architecture does – by eliminating most of that collection system. Employing creative system concepts and more “fail-safe” technologies, this scheme also makes the overall system cost effective to operate, and blunts environmental impacts inherent in “waste” water management.

Under a “One Water” strategy, water supply and storm water management would also be generally more distributed systems than they are under conventional practice.

The “traditional” view of storm water management centers on “efficient” drainage “away” from the development of increased runoff imparted by development, so as not to impart nuisance flooding of project grounds, and to assure that as this water flows “away”, it does not create downstream problems, either due to streambank erosion or overbank flooding. This “efficient drainage” viewpoint often results in whatever constructions used to attain those aims being “end-of-pipe”, essentially appended onto the project, rather than distributed facilities designed into the very fabric of the development.

An essential “One Water” strategy is to “retain, not drain” the runoff, at least up to the point that this water would have infiltrated rather than flowed “away” from the “native” site. The aim is to maintain as much as practical the “hydrologic integrity” of the site – that is, to maintain the rainfall-runoff response as similar to that of the “native” site as practical – and by treating multiple sites in a watershed in this manner, to maintain rather than degrade the hydrologic integrity of the watershed.

The means by which this would be accomplished would be implementing the “low-impact development” (LID) concept, imparting rainwater harvesting – either “formally” in cisterns or by capturing runoff in specialized landforms generally termed “green stormwater infrastructure” – on a highly distributed basis. Again, designed into rather than appended onto the development. When I first learned of LID, it immediately hit me that this is basically a “decentralized concept of storm water management”. So here too, “One Water” = the “Decentralized Concept”.

An example of this sort of distributed LID concept was illustrated in “… and Stormwater Too”, showing how rainwater harvesting from rooftops, permeable pavement, and rain gardens (bioretention beds) would create a highly efficient scheme to both hold more water on the land and to utilize the rooftop runoff to further defray landscape irrigation demands.

Another example is applying this concept to a big-box store parking lot, as is illustrated here. This shows how to indeed maintain, or better, the rainfall-runoff response of the “native” site, while providing water quality treatment just as a matter of course as the water flows through the site.

Regarding water supply, not only would building-scale rainwater harvesting (RWH) typically be a component of the storm water management scheme – so potentially creating a supply that could be used to defray water demands rather than just being drained “away” after being detained in the cistern – but some, even all, of the water supply strategy could be based on building-scale RWH. This all plays into what I have termed the Zero Net Water concept.

True to its name, Zero Net Water is a water management strategy that would result in zero demand on our conventional water supplies – rivers, reservoirs and aquifers. Under the Zero Net Water development concept, water supply is centered on building-scale rainwater harvesting, “waste” water management centers on project-scale reclamation and reuse, and stormwater management employs distributed green infrastructure to maintain the hydrologic integrity of the site. So basically it’s really another name for “One Water”. Together these result in minimal disruption of flows through a watershed even as water is harvested at the site scale and used – and reused – to support development there. In the general case, this concept might be approached – you might call it “minimum net water” – to defray but not eliminate demands on the conventional water supply sources.

Our conventional supply systems are watershed-scale rainwater harvesting systems, utilizing reservoirs, aquifers and streams as the “cisterns” to hold the water supplies awaiting various uses. Noting that an essential water use is maintenance of environmental integrity – e.g., maintaining aquifer levels so as not to reduce spring flows, keeping enough flow in streams to service various environmental functions, including delivery of water into bays and estuaries to maintain those ecologies. So we need to be saving as much water as we reasonably can, and minimizing disruption of flow through the watershed. The “minimum net water” approach would serve that end.

While it will not be belabored here, distributing the water supply system to the building scale creates an inherently more efficient system, as it eliminates transmission losses and evaporation losses from reservoirs, and it requires less energy, as the water needs to be moved only short distances, with small elevation heads. It would also be more economically efficient, as the water supply would be “grown” – thus paid for – in fairly direct proportion to water demand, one building at a time.

In closing, a more recent focus of “One Water” practice is the capture of air conditioner (AC) condensate, applying the water so captured to providing water supply, to defray demands on the “original” water supply source to the site. Clearly, condensate capture would also be a very highly distributed strategy, executed at the building or campus scale.

So it is that not only does “One Water” = the “Decentralized Concept” in the “waste” water management arena, “One Water” would optimally be a rather highly distributed strategy for water supply and storm water management as well. Moving from the conventional centralized “waste” water system architecture to the decentralized concept strategy has been a challenge for the mainstream of this field. Over the almost 4 decades I’ve been advocating for that paradigm shift, very little movement has been seen on that front. It is to be expected that moving off “end-of-pipe” management to a highly distributed LID strategy, and integrating building-scale RWH into the water supply strategy on a broad scale will be similarly challenging to the field, as these moves also require a paradigm shift.

Despite the “One Water” concept having been “a thing” in this field for many years now, despite years of “happy talk” around moving society toward a “One Water future” and such, we have seen precious little of all this hitting the ground. To the extent that, when a local environmental activist queried the U.S. Water Alliance – a major “cheerleader” for “One Water” – on examples where “total One Water” schemes, entailing all the water management functions, could be found, the response was … [crickets chirping]. One wonders, how much is that lack of movement in practice due to the paradigm shift to more decentralized schemes not having taken hold in the water resources management field? Indeed, we have a lot more work to do before it will become broadly recognized that “One Water” = the “Decentralized Concept”. But until that happens, it’s highly likely the movement toward “One Water” will continue to be very slow.

Or so is my view on this matter. What’s your view?

I recently read the book Water Always Wins by Erica Gies. A major theme is that to best manage water resources as they flow through our environment, in particular to promote and enhance sustainable water, we need to be imparting a “Slow Water” regime. We need to use management methods that blunt the rushing off of runoff and instead install means and methods that slow the flow, causing it to spread so that more of the water soaks in instead of running off. By these means, Gies argues, we can retain, and restore, the hydrologic integrity of sites, and by so treating a multiplicity of sites, of the watershed, so it would deliver more water supply.

A chapter in the book is about beaver, the undisputed champion in the animal kingdom at modifying and improving the hydrology of watersheds. The instinctive dam-building activities of beaver indeed create a Slow Water regime. They dam the flow, causing water to spread across the floodplain, filling up the “sponge” that landform creates, so storing much more water in the watershed than would occur otherwise. This slowing and retention of the water decreases downstream flooding, as more rainfall is detained/retained rather than zooming downstream. A good bit of this retained water would over time augment downstream baseflow, so improving the riparian ecology. The dams also retain sediment and so improve downstream water quality. All of this also stores carbon, and so helps to blunt climate change.

It struck me while reading that chapter that being like a beaver and creating a Slow Water regime is essentially what we did in the Villa Court project. The 3505 Villa Court project lies between Garden Villa and South 5^th Street, in the Bouldin Creek watershed in South Austin. It’s a 13-unit townhome project that was installed on 1.43 acres of formerly “vacant” land. The final layout of the project imparted 67% impervious cover of the land.

In 2010, I was approached by PSW, the developer of many townhome projects in Austin, to help them obtain the water quality permit they would need to execute this development. They related that a senior level person in the City of Austin Watershed Protection Department had told them, “You need a retention-irrigation system.” Won’t bore you with the details of that method, except to say it would have entailed encumbering the back yards of all the townhomes along the downslope edge of the property with tanks to store the runoff, and taken up just about every square inch of greenspace in the development plan to “irrigate” the water gathered into those tanks. I looked at that for, oh, about 2 or 3 nanoseconds, then said, “This is insane.”

I told them, we could provide the water quality treatment for this project with rain gardens, and we could do that without needing any variances. This surprised them, and the folks at Watershed Protection too, as no one had run this idea at them before that. But I showed them that the rules did indeed support the rain garden scheme. Besides meeting the formal water quality management requirements, the rain gardens would capture and insoak the “excess” runoff created by development and keep about as much water on the land as had been soaked up by the land in its “natural” state. This despite a rather high percentage of the land having impervious cover. So we proceeded to be like a beaver.

“Rain garden”, as a formal water quality device, is a term often used for a full infiltration bioretention bed. This device is a vegetated bed of a specialized soil mix that intercepts runoff from its drainage area. Under Austin rules, the volume of water to be captured is termed the “water quality volume”. This is the volume of runoff from the drainage area generated by the “water quality depth” of runoff from the area. The water quality depth required to be captured under Austin rules increases with the percentage of impervious cover over the drainage area tributary to each rain garden. The idea is that the more impervious cover, the more the balance would be shifted from infiltration to runoff of rainfall, so a larger volume of water would need to be captured in order blunt that shift.

The captured water volume would be stored in the bed until it is infiltrated into the soil under and surrounding the rain garden. This process both intercepts pollution entrained in the runoff – “treating” it as it flows down through the biofiltration bed root zone – and retains the water quality volume on site, rather than allowing it to run directly off, so helping to control and mitigate downstream flooding and channel erosion.

The 3505 Villa Court water quality management plan entailed several rain gardens, distributed around the site. Five of them intercepted runoff from rooftops, pavement and green spaces. Another seven captured runoff from a rooftop that could not be routed to one of the other five rain gardens, so that these areas of impervious cover would be “treated”. The project layout is shown in the figure below.

This shows how indeed we intercepted, spread and infiltrated runoff flows. As noted, this restores to some degree the rainfall-runoff response of the “natural” site, as it blunts the increase in runoff immediately leaving the site that installing impervious cover on the site would otherwise impart. This indeed mimics to an extent the impacts that beaver have on a stream, only this is applied in the uplands rather than in a streambed, intercepting and insoaking the increased runoff on its way to a stream. But the ultimate impact is largely the same, damming up the flows, holding – storing – water on the land. And reaping the benefits of that.

Some of this water would infiltrate and ultimately migrate to a stream, to impart baseflow, just as water seeping out of the floodplain “sponge” that beaver create would impart baseflow downstream. As noted, the rain gardens also intercept and store sediment entrained in runoff, just as beaver ponds do, and also intercept and “treat” pollutants that developing land causes to be entrained in runoff. Then too, there would be carbon sequestration in the rain garden beds. So in imparting the water quality management scheme at Villa Court, we were being like a beaver, mimicking the ecological wisdom they evolved to deliver to the landscape.

Now of course the retention-irrigation scheme, entailing interception of runoff and subsequently spraying it over landscape to largely infiltrate the water that would have otherwise run off, would have also helped to maintain the hydrologic integrity of the site. But that would have been acting like a human, using a failure-prone mechanical system, requiring assured power supply, to redistribute the water over the site. Noting that little actual irrigation benefit would be obtained by spraying the captured runoff over the green spaces, because the storage tanks have to be evacuated only a couple days after the rain fell, which had just “irrigated” those spaces. Any sediment removal would have to be accomplished by “actively” cleaning the storage tanks, into which the “raw” runoff would flow. Rather than incorporating the sediment into the plant-soil system on the site just as a matter of course, this would create a “waste” stream that would have to be “disposed of”. Then too, the shallow-rooted turf that would be “irrigated” would not sequester anywhere near the level of carbon that the deep, more biologically complex rain garden root zone would.

All this illustrates we would be well served to be like a beaver in the way we design sites for water quality management, in the manner we did at Villa Court. Damming up water flows to create a Slow Water regime at the site level, holding up and spreading out the flows, infiltrating on the site “excess” runoff imparted by development, rather than it rushing away, so retaining/restoring the hydrologic integrity of the site. And by a multiplicity of such sites in a watershed, we can retain/restore the hydrologic integrity of the watershed. It could fairly be stated that if every site in the Bouldin Creek watershed had been treated like Villa Court was, we would still have baseflow in Bouldin Creek. And that would enhance the ecology of the whole watershed.

Almost like re-introducing beaver to the watershed would. So when considering how to manage storm water as a site is being developed, be a beaver.

March 28, 2022

Office of the Chief Clerk, MC 105

Texas Commission on Environmental Quality

P.O. Box 13087

Austin, TX 78711-3087

COMMENTS TO TCEQ REGARDING “PRISTINE STREAMS PETITION”

A petition, styled as the “Pristine Streams Petition”, permit no. 2022-014-PET-NR, has been filed with the Texas Commission on Environmental Quality (TCEQ) requesting that TCEQ adopt a rule that would bar any discharges from TCEQ-permitted “waste” water treatment plants into 23 stream segments that monitoring has found to have very low “native” concentrations of phosphorus. The aim of this proposed rule is to keep these stream segments “pristine”, in regard to their phosphorus concentrations, and thus free of “excess” algae growth that it has been documented “waste” water effluent discharges into such streams will induce.

I agree that such a rule should be promulgated, in an attempt to accomplish its stated aim. This rule is truly the minimal effort that the State of Texas should consider in an effort to blunt degradation of water quality in the waters of the state. It is in fact rather astounding that it would take a petition to get TCEQ to consider such a rule, as protecting “pristine streams” from the sort of degradation due to “waste” water discharges that have been witnessed is really in the “no-brainer” category. But as is reviewed below, establishing such a rule really needs to be just the beginning point of a larger effort to improve the state of “waste” water management in the state of Texas, including – if not especially – in regard to the fate of this water resource that we mistakenly identify as “wastewater”.

You see, a very basic problem that plagues this societal function is that TCEQ insists upon viewing this function through the lens of “disposal of a nuisance”, when really what society needs – in this region in particular, with the looming water supply issues we face – is for us to address this function with a strong emphasis on “utilization of a resource”. As TCEQ appears to “understand” this function, it is required that a full-blown “disposal” system be in place before an applicant can even start to consider the resource value of the water and how best to reuse this water so as to defray demands on the “original” water supply.

The practical outcome of TCEQ’s insistence on the “disposal of a nuisance” focus is that it is difficult to design reuse into the very fabric of development, so as to practically maximize the reuse benefit of this water resource. Which is how we should be addressing this societal function, just as a matter of course.

Under the “disposal of a nuisance” construct, the permitting process is typically a two-part endeavor; first a permit for the “disposal” system, and then another permit to route this water resource to reuse. The “clunkiness” of this process is an open-ended “invitation” to applicants to just throw this water resource away, to just do the “disposal” system and not incur the extra work, and cost, of addressing the reuse part. That is why it has been witnessed that the majority of “land application” systems are in effect “land dumping” systems, with the effluent routed to “disposal fields” – where any irrigation benefit is just coincidental – as the manner in which to make this water “go away”. Indeed, in every reference to the Dripping Springs application to expand its dispersal fields, for example, the proposed fields are called “disposal” fields. Indeed, while Dripping Springs asserts that they intend to reuse their effluent rather than “dispose” of it, it appears that all their efforts to date indeed focus on “disposal”, with no actual reuse system infrastructure being apparent. This is a dynamic that has to be blunted, with the process reoriented to focus on the beneficial reuse of this water resource, if local society is to most effectively address its looming water supply crisis.

Then too it must be recognized that centralization of “waste” water issuing from miles around to one point source treatment plant is the whole predicate for even considering stream discharge as the fate of this water resource. Indeed it is a motivator to just discharge into a stream to “get rid of it”. Once the “waste” water has been gathered to that one point source, stream discharge will always be the “cost efficient” way to “manage” that flow (depending perhaps on whether TCEQ would assign effluent limits that would not degrade the receiving stream’s water quality, which it does not seem inclined to do), especially given the high cost that would already be incurred to gather that flow to the centralized point source. A large majority of the total cost of a conventional centralized “waste” water system is the cost of the collection system, investments that really do nothing but move the stuff around, not really contributing to resolution of the root problem of managing that water resource. So once a community has dedicated a considerable investment to making that water “go away”, they would be less than excited to incur a similar investment to redistribute this water resource from the centralized point source to points were it could be beneficially reused, often being back where the water came from in the first place!

So it is that we should be considering how we can decentralize the “waste” water system, to shorten the water loops so as to minimize the investment dedicated to just moving the stuff around, and better enable designing reuse of this water resource into the very fabric of development. But this runs afoul of TCEQ’s “regionalization” policy, stated in TAC Chapter 26.081. That this holds sway over the institutional infrastructure that addresses this societal function is attested to in Dripping Springs’ “moratorium” ordinance, which states that the city “understands” the conventional centralized system architecture to be the only form of “waste” water system infrastructure that is “blessed” by TCEQ. As if this is religion, not science and technology, so that no considerations of the form and function of that infrastructure that do not conform to the “Book of TCEQ”, Chapter 26, verse 081, is allowed to be countenanced. A moment’s reflection should be plenty to conclude that there is more than one way to skin this cat. But at present it appears that most of our institutional infrastructure will not countenance any such reflection. Again, as if this is religion.

The need for re-examining the infrastructure model is perhaps most critical in exactly the areas such as those where those 23 “pristine” streams lie. A major reason they remain “pristine” is because there has been little development in areas tributary to these streams. So these are places where we have a “blank slate”, where we are not beholden to sunk costs in the conventional centralized system architecture, so could readily entertain another infrastructure model. That was, for example, the situation in which Dripping Springs found itself, yet again they chose fealty to the “Book of TCEQ” over a rational consideration of the full range of options available to them.

One such option is a “decentralized concept” strategy. Cut to its most basic, the decentralized concept holds that “waste” water is most effectively and efficiently managed by treating, and reusing to the maximum practical extent, the “waste” water as close as practical to where it is generated. As noted, this approach would work with, rather than against, the whole idea of integrating reuse into the very fabric of development, as if management of this water as a resource from its very point of generation was a central point. Rather than considering that whole matter as something you might append on to redistribute the water gathered at the end of the pipe, as if the whole matter of this water being a resource was just an afterthought.

This “decentralized concept” idea has been out there for decades, having been the subject of many works considering the concept, much of it funded and conducted under the auspices of EPA. Indeed, a “finding” was issued by Congress in the 1990s that this general approach is a legitimate manner of addressing “waste” water management needs. It is generally understood among those who have chosen to examine this matter that the decentralized concept strategy has the potential to produce “waste” water systems that are more fiscally reasonable, more societally responsible, and more environmentally benign than those systems which implement the conventional centralized system architecture. But in practice any meaningful consideration of the road not taken has been blunted, so that good examples of such practice remain rather few and far between. In no small part due to such circumstances as “regionalization” being an “article of faith” in TCEQ.

However, in the context of “developing” areas, this matter has been presented to TCEQ, and to society’s various institutional actors – city administrations and utility operators, the engineering community, the development community, and the environmental community. An example of this was presented on the Waterblogue in 2014, entitled “This is how we do it” (https://waterblogue.com/2014/09/24/this-is-how-we-do-it/, considered to be part and parcel of this comment), showing in the context of one development in the Dripping Springs hinterlands how a reuse-focused decentralized concept strategy could work in that environment, in a manner that would not only integrate reuse into the very fabric of the development, thus maximizing ability to defray demands on the “original” water supply, but would also be more globally cost efficient than centralizing that development into a Dripping Springs “regional” system. The fiscal, societal and environmental advantages of this strategy were further reviewed on the Waterblogue in 2016, in the piece entitled “Let’s Compare” (https://waterblogue.com/2016/09/26/lets-compare/, considered to be part and parcel of this comment). This application of the concept was explicitly reviewed with TCEQ, and it was the conclusion of the folks with whom it was reviewed that this strategy could be permitted under current rules. So it could readily deliver those fiscal, societal and environmental advantages in many developments in the hinterlands, such as those that may be installed on or near the “pristine” streams, NOW.

So it is that there is ample reason to reconsider the “dogma” of “regionalization” and to consider the road not taken. In particular in areas where there is little sunk cost in the ground that must be respected going forward, such as the areas where, in the main, those 23 “pristine” streams are located. Reinventing the “waste” water system infrastructure model in those sorts of areas can deliver systems that are more fiscally reasonable, more societally responsible and more environmentally benign than would be attained by pressing down on the cookie cutter and spewing out the conventional centralized system architecture, without regard to the nature of the circumstances. TCEQ must examine this matter and consider how it can best serve the citizens of Texas in regard to how the “waste” water resource is to be managed, especially around those “pristine” streams.

So again, please do protect those 23 “pristine” streams from “waste” water discharges. This is simply a “no-brainer” thing to do. But also open up the whole process of planning for how growth and development will be managed in such areas, to take a long hard look down the road not taken. As that all the difference could make. [apologies to Robert Frost]

Respectfully submitted,

David Venhuizen, P.E.

Austin, Texas