Indirect potable reuse in our future?
A past project I was involved with involved a look at the feasibility of using wastewater to recharge the Biscayne aquifer In the vicinity of a utility’s potable water supply wells. The utility was feeling the effects of restrictions on added water supplies, while their wastewater basically unused. So they wanted a test to see if the wastewater could be cleaned up enough to pump it in the ground for recovery downstream, with the intent of getting added allocations of raw water. Assuming the water quality issues could be resolved, the increased recovery would solve a number of water resource issues for them, and the cost was not nearly as high as some thought.
So we tested and using sand filters, microfiltration, reverse osmosis, peroxide and ultraviolet light, we were successful in meeting all regulatory criteria for water quality. The water produced was basically pure water – not constituents in it, and therefore it exceeded all drinking water standards. We demonstrated that technologically the water CAN be cleaned up. The only issue is insurance that the treatment will always work – hence multiple barriers and the ground. This was an indirect potable reuse project and ended because of the 2008 recession and the inability to of current water supply rules to deal with the in/out recovery issues.
The indirect reuse part was the pumping of the water into the ground for later withdrawal as raw water to feed a water treatment plant, as opposed to piping it directly to the head of their water plant. But recovery of the water can be a challenge and there is a risk that a portion of the injected water is lost. In severely water limited environments, loss of the supply may not be an acceptable outcome. Places like Wichita Falls, Texas have instead pursued more aggressive projects that skip the pumping to the ground and go straight into the water plant as raw water. Technologically the water CAN be treated so it is safe to drink. The water plant is simply more treatment (added barriers). So, with direct potable projects, monitoring water quality on a continuous basis maybe the greatest operational challenge, but technologically there is no problem as we demonstrated in our project.
The problem is the public. You can hear it already – we are drinking “pee” or “poop water” or “drinking toilet water.” The public relations tasks is a much bigger challenge because those opposed to indirect and direct potable projects can easily make scary public statements. Overcoming the public relations issue is a problem, but what utilities often fail to convey is that many surface waters are a consolidations of a series of waste flows – agriculture, wastewater plants, etc. by the time they reach the downstream water intake. Upstream wastewater plants discharge to downstream users. But the public does not see the connection between upstream discharges and downstream intakes even where laws are in effect that actually require the return of wastewater to support streamflow. So are rivers not also indirect reuse projects? In truth we have been doing indirect potable reuse for, well ever.
We have relied on conventional water plants for 100+ years to treat surface waters to make the water drinkable. The problem is we have never educated the public on what the raw waters sources were, and how effective treatment is. Rather we let the political pundits and others discuss concerns with chemicals like fluoride and chlorine being added to the water as opposed the change in water quality created by treatment plants and the benefits gained by disinfectants. That message is lost today. We also ignore the fact that the number one greatest health improvement practice in the 20th century was the introduction of chlorine to water. Greater than all other medical and vaccine advances (although penicillin and polio vaccines might be a distant second and third above others). Somehow that fact gets lost in the clutter.
Already the Water Reuse Association and Water Research Foundations have funded 26 projects on direct potable reuse. Communicating risk is one of the projects. The reason is to get in front of the issues. You see, playing defense in football is great and you can sometimes win championships with a good defense (maybe a historically great one, but even they gamble). Defense does not work that way in public relations. Offense usually wins. Defenses often crumble or take years to grab hold.
The failure of utilities to play offense, and the failure of elected officials particularly support playing offense is part of the reason we struggle for funds to make upgrades in infrastructure, to perform enough maintenance or to gather sufficient reserves to protect the enterprise today. And it remains a barrier to tomorrow. Leadership is what is missing. It struck me that when looking at leaders, what made them leaders was their ability to facilitate change. Hence President Obama’s campaign slogan. But talking about change and making real changes are a little more challenging (as he has seen). You cannot lead without a good offense, one that conveys the message to the public and one that gets buy-in. With direct and indirect potable reuse, the water industry has not changed the perception of “toilet water.” That needs to change. We need to be frank with our customers. Their water IS SAFE to drink. They do not need filters, RO systems, softeners, etc., or buy bottled water, when connected to potable water supplies (private wells, maybe). We CAN treat wastewater to make it safe, and the technology tis available to make it potable. . The value they pay for water is low. Yet in all cases, others, have made in-roads to counter to the industry. That happened because we play defense.