All wastewater is reused, it’s a matter of how.
When municipalities treat their sewage to federal and state standards, it is released into some sort of surface water reservoir whether it’s a creek, stream, river or lake. The released water is cleaner than the reservoir it is being released to. It eventually is picked up and used by municipalities for their drinking water supply.
For example, wastewater effluent from the North Texas town of Wichita Falls flows down the Wichita River to Lake Texoma. Several other cities use the lake as their public drinking supply water source.
The difference with the innovative project Wichita Falls is working on and the reason it is receiving worldwide media attention is that there isn’t the natural environmental buffer between the treated wastewater effluent and the public drinking supply.
You might be asking why a town would even attempt such drastic measures. Well, Wichita Falls is currently suffering through its worst drought on record. It is so bad, in fact, that the town is nearing Stage 5 drought catastrophe restrictions.
Wichita Falls water consumers are already prohibited from using the public water supply to water their lawns or clean their driveways and sidewalks. Once Stage 5 hits, swimming pools and golf courses will not be allowed to use the public water supply and restaurants, bars, clubs and school cafeterias cannot clean a kitchen or food handling area with a spray hose, among other restrictions.
Given this backdrop, Wichita Falls is doing everything it can to come up with a solution, including a proposed plan to pump the treated wastewater effluent (that is cleaner than the lake water used for the public drinking supply) through a 12-mile pipe to the water treatment plant.
Once at the plant, it will be treated through microfiltration and reverse osmosis systems. At this point the water would be 100-percent safe to drink. But, the state requires the city to remix it with lake water, meaning it has to go through a conventional water treatment process before it can be introduced to the distribution system.
The Wichita Falls project is being highly scrutinized by the Texas Commission on Environmental Quality because the blend will be 50-percent wastewater effluent and 50-percent lake water.
The city conducted a 45-day full-scale verification test from Jan. 29-March 10, collecting a variety of samples for a report sent to TCEQ on March 28. All of the tests met or exceeded TCEQ requirements for public drinking water.
More than 7 million gallons of water will flow through the pipe daily, and once all three treatment processes are complete, about 5 million gallons of water will be added to the drinking supply daily. That’s more than 1/3 of what’s being produced daily in Wichita Falls, and eases the strain on the drought-stricken reservoirs.
The long-term project is to run a pipe from Wichita Falls' wastewater treatment plant to Lake Arrowhead (the city's primary reservoir) and release the wastewater effluent into the lake. The direct potable reuse project was the most cost-efficient and quickest way to get water Wichita Falls was losing daily back into the system.
Between this project and a significant recent investment made in cloud seeding (the process of shooting chemical flairs into storm systems as a means of creating more rainfall), Wichita Falls is hoping to stay afloat until the drought ends.
To find out more about the Wichita Falls water reuse project and get complete drought coverage, visit the Lifeline project.