“Truly, Councilman, can you stand behind a plan that proposes to focus on an infrastructure model that, by Austin Water’s own reckoning, will only attain 12% reuse in 55 years? Do you not find that astounding in its lack of ambition?”
That is the message I wrote to the Austin City Council member representing my district, following up my argument to Austin Water about Water Forward, the city’s plan for how water is to be managed around here over the next 100 years. Sent under the subject line, “Austin Water Backward” – stark, and yeah, a bit snarky. But read the argument for yourself, and make your own determination if clinging to the past’s business as usual is likely to be the most fiscally sound plan, the plan that would best serve the local and regional water economy over the next century. Or, since we have management concepts available that could approach 100% reuse at the project scale, if it’s questionable that backward looking plan is Austin’s pathway to sustainable water, if it lacks sufficient ambition to get us there.
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A look at the table entitled “Summary of Water Forward 2024 Strategies, 2030-2080” on page 31 of the 2024 Water Forward plan update shows that Austin’s planning is rooted in the presumption that the prevailing, essentially 19th century water infrastructure model will simply be extended and perpetuated, with little focus on anything else. I argue that this sort of backward looking strategy will not be a sufficiently ambitious pathway to sustainable water, and that Austin Water’s apparent conclusion it is the cost efficient manner of proceeding is likely rooted in flawed analysis.
The situation is exemplified by the “Non-Potable Water Reuse Strategies” part of the table, recapitulated below. This indeed indicates the expectation that wastewater system development going forward will continue to focus on piping flows from hither and yon to centralized treatment plants, and that non-potable reuse will continue to be focused mainly on the “purple pipe” system redistributing reclaimed water from those plants to points of use. The latter is a strategy that has been, throughout its 30 year operating history, kept afloat by infusions of money from other sources, and is not expected to ever pay for itself. Yet, the table shows, Austin Water seems intent on doing it mainly that way.
Non-Potable Water Reuse Strategies (Acre-Feet/Year)
| Water Forward Strategies | 2030 | 2040 | 2050 | 2060 | 2070 | 2080 | Annual Cost $/ac-ft/year |
| Centralized Reclaimed | 1,100 | 8,200 | 12,900 | 17,600 | 22,300 | 26,900 | $2,243 |
| Decentralized Reclaimed | 0 | 200 | 500 | 800 | 1,100 | 1,300 | $5,158 |
| Onsite Reuse | 1,100 | 4,000 | 5,700 | 7,300 | 9,000 | 10,600 | $8,957 |
| Total Reuse Attained | 2,200 | 12,400 | 19,100 | 25,700 | 32,400 | 38,800 | —- |
On “decentralized reclaimed”, I’m still wondering how that whole idea is understood at Austin Water, as outreach efforts to discuss this matter have been … well, I’d say rebuffed, but to be rebuffed, there would have to be evidence that it was looked at to begin with … Sorry, snarky again. But just highlighting that all throughout the decade that Water Forward has been in process, this whole idea – that can approach 100% reuse on each project – has been marginalized. The table indicates so little consideration of this strategy that it’s expected NO “decentralized reclaimed” would come on line by 2030. And it shows that “decentralized reclaimed” is projected to be a paltry 5% of “centralized reclaimed” reuse in 2080. This does indicate there will be little focus on if and how we might transform the infrastructure model over the next 55 years!
That 55-year timeline we’re talking about here bears some consideration. In 1999 I wrote a piece, aimed at fostering a more focused discussion of the then-pending 50-year water deal with LCRA, entitled “Is a Billion Dollar Crapshoot Our Best Public Policy?” The example of “silicon” plants – a totally unknown technology in 1949 – having become a significant part of the industrial sector here, drawing a sizable population to Austin, was offered to illustrate that it’s pretty impossible to know with any certainty what Austin will be like 50 years into the future. Indeed, it’s a crapshoot. The article posed the many ways the water future may be different from the past, how the water infrastructure model may evolve considerably over the ensuing 50 years, all being echoed by many “futurists” even back then, a quarter century ago. Most of which could be encapsulated under the now popular banner of “One Water”, the idea that all water flows have resource value that should be maximized, rather than those flows being “disposed of”. A perusal of that review would immediately illuminate that Austin Water has not really pursued much of that over the last 25 years. And again, the apparent presumption of the 2024 Water Forward plan is that, in regard to wastewater management, little will be done in that vein over the next 55 years.
Which we can see by examining the projections in the Water Forward plan. Austin Water seems to not want to share the magnitude of current wastewater flow. The best estimate I’ve been able to derive is from the latest rate study, from which it seems implied that current wastewater flow is about 87,000 acre-feet over the year. If this is taken as the flow in 2030, noting it will undoubtedly increase by then, reuse through the “purple pipe” system in 2030 would be only 1100/87000 = 1.3% of total wastewater flow. This indeed shows the limited reach of this mode of reuse, that after 30 years of developing the “purple pipe” system, this is the paltry level of reuse that’s being attained.
Water usage projections in the Water Forward plan can be parsed to guess that wastewater flow in 2080 would be around 2.5 times the current flow, or 2.5 x 87000 = 217,500 acre-feet over the year. Presuming this basis, the table shows expected “centralized reclaimed” reuse through an expanded “purple pipe” system would be 26900/217500 = 12.4% of total wastewater flow. A robust growth, at almost a 10-fold increase in share of total flow, but still far short of making the “One Water” ideal, utilization of the water resource rather than “disposal” of a perceived nuisance, the focus of this societal function. Certainly, since the collection system typically represents 70-80% of total wastewater system cost, the pipe-it-away infrastructure model reflects that fiscal resources would be far more focused on “disposal” than on reuse.
Meanwhile, it’s projected that “decentralized reclaimed” would have achieved a penetration of only 1300/217500 = 0.6% by 2080. Reflecting, over 55 years, an almost total lack of focus on if, where and how to transform the infrastructure model, apparently rejecting the “One Water” decentralized concept strategy, which can approach 100% reuse on each project.
Looking at costs for these options, Austin Water projects the cost of implementing “decentralized reclaimed” would be 2.3 times that of “centralized reclaimed” reuse, $2,243 vs. $5,158 per acre-foot/year. One might guess this is their basis for continuing to focus system development on the prevailing conventional pipe-it-away infrastructure model. But based on everything I have observed in this field, this does not make any sense. The decentralized concept strategy, in the setting of urban fringe and hinterlands development, always shows to be more cost efficient, on a global cost efficiency rating. As set forth, for example, in This is how we do it and, more explicitly, in Let’s Compare. Which is likely the key to why the Austin Water projections show the opposite, rather extremely so; global cost accounting is not their standard.
One guesses that the costs of “centralized reclaimed” are limited to the “purple pipe” system, not accounting for the cost of “producing” that reclaimed water flow to begin with – the costs of wastewater collection and treatment – and probably not accounting for costs to implement end uses either. While for “decentralized reclaimed”, it is guessed that the total system costs were presumed – the costs to collect, treat, redistribute and utilize this water resource. Rather distorted, not an apples-to-apples comparison. But what Austin Water seems to be basing its desire not to examine the infrastructure model upon, rather wanting to simply forge ahead presuming the future will be just like the past.
Now of course Austin Water can legitimately claim that the costs of collection and treatment to “produce” that reclaimed water supply are sunk costs, as those facilities are already in place, so should not be accounted as a cost factor for “centralized reclaimed”. True enough for the portion of the system that is currently in place. Remember though we are looking at policy and strategy over a 55 year timeline here, over which it is projected that wastewater flow would increase 2.5-fold. This will require that lines be extended and/or upgraded, new lift stations would be needed and/or current lift stations upgraded, and new treatment capacity would have to be added. None of these are sunk costs.
Austin Water might also argue that these new costs would be incurred in any case to impart wastewater management regardless of whether the effluent would be reused. But of course that argument only holds water if wastewater system capacity would be expanded only via extension of the prevailing conventional pipe-it-away infrastructure model. If areas of new development – on the urban fringe or in the hinterlands where lines would need to be extended, or for infill development that would require upgrading of existing facilities all along the way from the development to the centralized treatment plant – were to be managed instead by pursuing the “One Water” decentralized concept strategy, those costs may be obviated, saving as noted in First ‘Logue in the Water untold costs by never having to build another trunk main. Or to extend/upgrade the loss leader “purple pipe” system.
This leads us to the “onsite reuse” category, for which about a 10-fold growth is projected, from 1,100 acre-feet/year in 2030 to 10,600 acre-feet/year in 2080. Impressive on the surface, but is it really? When EVERY commercial and institutional building is a candidate for this form of water conservation, what level of dedication to reuse does a 10600/217500 = 4.9% penetration over 55 years represent? One wonders what Austin Water thinks would be so limiting a proliferation of this practice?
For one thing, maybe it’s a poor appreciation of “reuse”? Austin’s highly touted Onsite Reuse Ordinance does not actually very much address reuse. It’s focused on site-derived flows, mainly harvested rainwater and condensate, the usage of which would be “original” use, not REuse. That is a term of art generally applied to reclaimed wastewater, which this ordinance gives very short shrift. It does not even ALLOW “onsite” reuse of reclaimed wastewater except by variance. So it appears that Austin Water is really not that into this “One Water” idea of reuse at the building scale.
Which is a shame, since in its most “advanced” form, this strategy would render commercial and institutional buildings, or whole campuses of such buildings, water independent, running on Zero Net Water, as laid out over a decade ago. The legitimacy of which is now well recognized, being marketed, for example, by Texas Water Trade under the banner of “Net Zero Water”. But Austin Water seems to not expect such developments to ever “unhook” and become their own water supply centers, rather they might only just defray some non-potable usage, while the prevailing conventional pipe-it-away infrastructure model will continue to be the major mode of management across such developments. Failing to approach the essentially 100% reuse that is readily available here.
As to cost of “onsite reuse”, at $8,957, 4 times that of “centralized reclaimed”, doesn’t seem all that cost efficient. But … It is not likely that relieved capacity on either the potable water supply system or the centralized wastewater system are accounted for. If a building were to go Zero Net Water, there would be no need to extend – or in the case of “nodal densification” that was all the rage in the Imagine Austin program some years ago, upgrade – waterlines to and wastewater lines from these developments. Little doubt none of this was recognized in the cost accounting of these “onsite reuse” systems. Here again, the cost of a system to collect, treat, redistribute and utilize the site-derived water flows is likely being compared to the cost for ONLY the redistribution system for the “centralized reclaimed” option. Not the apples-to-apples comparison that, in a rational process, would be the standard.
Also, the asserted cost may be inflated over what it needs to be, because it has so far appeared that Austin Water, and Texas Water Trade as well, presume that the treatment units for building-scale reuse would be activated sludge units, imparting high operating costs. As discussed in Appropriate Technology, using technologies more appropriate to the building scale would render these systems more cost efficient, so would further reduce – eliminate? – the asserted cost disadvantage of building-scale reuse.
All of this reflects that there seems to be no “Visionary-in-Chief” at Austin Water, and so the process is being controlled by “mainstreamer” viewpoints, failing to imagine that the future might be anything but an extension of the past. So what we have here could indeed be quite fairly seen not as a Water Forward plan, rather a Water Backward plan. Certainly, in regard to the matters discussed here, a backward looking plan. One which just presumes that the future will be very like the past, just presumes that the prevailing, essentially 19th century water infrastructure model will be extended and perpetuated, world without end.
As was set forth in One More Generation, we need to get past this backward looking mental model, essentially just rearranging the deck chairs as the ship goes down. On behalf of everyone’s children and grandchildren, we should all ask Austin Water to consider if this is the manner in which it really should be proceeding. Should we really be good with a plan this astounding in its lack of ambition?
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