Droughts, wildfires and hurricanes — whether you “believe” in global warming or not — these climatic events seem to be increasing in severity, and they are having an effect on freshwater resources.
The term “gray water” brings to mind dingy, scummy water, but it is actually just water we constantly waste when showering, bathing, brushing our teeth, etc., and increasingly cities and towns are looking for ways to reclaim that wasted water and reuse it.
So, the gray water issue is becoming more black and white — those who are or aren’t reclaiming water — and is spreading throughout the United States.
This is nothing new for California and other western states where continuous droughts have forced them to conserve water for decades. But extended periods of dry weather have been waking the rest of the country up to the need to be more conservative about this precious resource.
The Drought Management System report for June 2018 showed most of the Southwest and western states are experiencing severe to extremely dry conditions while southern states were moderate to abnormally dry conditions — conditions that apply to some of the Pacific Northwest and parts of the upper Midwest.
A 2013 Government Accountability Office report showed that 40 out of 50 state water managers expect water shortages in some part of their states under average conditions through 2023. Fifteen of those states predict local shortages; 24 expect regional shortages; eight states reported no expected shortage; two were uncertain; and Montana is expecting statewide shortages.
Then a May 2014 GAO report showed 36 states were using reclaimed water; 19 out of 49 were recycling stormwater; 18 out of 50 were using desalination; and 43 out of 50 reported states have “enforced, required and/or provided incentives for water conservation.”
And in states where flooding is the issue, freshwater resources are at times becoming contaminated by salt water and storm runoff .
The city of Davis doesn’t have a municipal system in place for reclaimed water, but its citizens are involved in doing so on their own.
“In the city of Davis, the wastewater treatment plant is over 4 miles from the city limits, so at this time it has been determined that it is not yet feasible to supply recycled water to current developments,” said Greg Mahoney, chief building officer and assistant director of community development and sustainability.
However, there is a citizen advocacy group in town called Cool Davis and city staff members participate in its events.
“Cool Davis is an active network of residents, community organizations, businesses and community institutions committed to implementing the city of Davis’ Action and Adaptation Plan,” Mahoney said.
“The most straight-forward use for gray water is sub-surface irrigation,” Mahoney said. “If recycled or gray water is used for above-ground irrigation, then it must be treated to specific standards. Some systems are designed to provide water for flushing toilets, but these systems have filtration, treatment and additional cross connection prevention measures and inspections are required.”
According to Mahoney, the city is reviewing a proposed ordinance that was provided to city staff by a group led by a certified gray water designer and installer who is active in a local water advocacy group. He said staff is still in the process of reviewing the ordinance, so it hasn’t been brought to the public yet for comment.
The city does support its residents’ installation of gray water systems. Mahoney said although the city doesn’t have a system in its municipal buildings, any of the systems listed on its website could be used in public or office buildings, but he added, “Those types of buildings don’t generate as much gray water as residences.”
The biggest benefit for cities and towns to promote and enact reclaimed water systems is the “reduction in potable water use for irrigation.”
He said if cities are considering implementing a program, he’d suggest “identifying sources of recycled and gray water and determine if it makes sense to offset the potable water use with these systems.”
The city of Naples has had much success with its voluntary alternative water supply program. In parts of the city where the program has been implemented, a high percentage of residents have opted in.
Naples Utilities Director Robert “Bob” Middleton said the city started in 1988 by using reclaimed water to irrigate 10 golf courses. In the mid-2000s, Naples began working on a master plan.
“Rather than delay until resources were critically challenged, Naples took a proactive position, defying the fates and their consultants, and implemented an inventive alternative water supply program as part of their 20-year integrated water resource plan,” Middleton states in a report compiled about the program.
According to this report, Naples’ per capita water consumption was among the highest in Florida at 373 gallons per day, 65 percent of which was being used for irrigation. With an anticipated population increase over the next 30 years, the city wouldn’t be able to meet the projected water demand because of insufficient well supply and its water treatment plant nearing maximum capacity. In addition, the intrusion of fresh water from the Golden Gate Canal into Naples Bay was creating an environmental concern.
In 2008 the Naples City Council considered options “with proposals ranging from constructing a new water treatment plant using reverse osmosis technology with a staggering price of $67 million to a $25 million alternative water supply program proposed by the utilities department, which had the potential to offer even more benefits than a new plant,” Middleton stated.
“The council decided instead of building the reverse osmosis plant to keep it as it was and expand the program to residential customers, but we needed more water,” Middleton explained in a phone interview. “So we went to the Golden Gate Canal to supplement our reclaimed water system.”
Middleton said as part of a feasibility study, the city conducted a survey of residents in particular areas and got “a pretty good response.”
“We targeted certain neighborhoods and looked at parts of town that were using excessive amounts of irrigation,” he said.
Those areas were already experiencing issues with water pressure, too. Running a dual-pipe direct to the reclaimed water system transferred the water demand, which saved 2.5 to 3 million gallons of drinking water.
“Without doing anything other than that, the water pressure in that area improved, and we had an 87 percent connection rate,” he said.
“The simple fact is they’d be paying half of what they’d been paying for their water.”
Naples started infrastructure construction to those neighborhoods in 2006 and completed it in 2008. So far infrastructure costs have been around $18 million.
The initial phase of the staff-initiated alternative water supply program had several objectives, including create a five-year alternative water supply; preserve aquifer water supply by reducing per capita daily water consumption; utilize water collected in the Golden Gate Canal; convert treated wastewater, or treatment plant effluent water, from a waste by-product to a resource; minimize capital investment in new treatment plant and wells; and stabilize or reduce customer utility bills by minimizing capital investment and operating costs.
Middleton stated that “addressing the water supply was the first order of business.” Capturing fresh water from the Golden Gate Canal and combining it with treated effluent water from the wastewater treatment plant would create a supply for an existing reclaimed water distribution system that provided the irrigation for the golf courses.
City officials quickly realized that they would need storage capacity for those times when demand was high and the water levels were low. After completing studies, they drilled the “deepest aquifer storage and recovery wells ever done in Florida, creating storage so far below ground — 1,000 feet deep — that it would not impact the drinking water supply.”
Middleton said because the ASR wells have a small footprint, workers were able to construct the wells onsite at the wastewater treatment facility where necessary infrastructure was already in place for treatment, disinfection, etc. Not only efficient, it also eliminated expensive land acquisition and capital expenditures and minimized operating costs. The only new equipment needed was a pump station and transmission main to bring the water from the canal 2.5 miles to the wastewater treatment plant. When that was completed, the water distribution lines were extended to the highest potable water use areas.
Middleton said the use of these deep wells to store alternative water supplies was recognized as an “inventive and resourceful solution to a complex problem,” and the Southwest Florida Water Management District awarded Naples a $9 million grant to fund the project.
Middleton cited several benefits for municipalities to have a reclaimed water program.
He said the environmental benefits are many, and specifically for Naples, the program eliminated effluent discharge into the river and Naples Bay, reducing the nutrient loading by 40 tons.
“We are a 100 percent reclaimed facility — 100 percent of the water goes right back out into the reclaimed system for irrigation,” he said.
“The demand for potable water resources was reduced by 46 percent, saving 4 million gallons a day, and we continue to expand.”
The city expanded its plan to encompass four phases and 20 years. The latest phase of expansion was completed last year, and there are now 1,200 reclaimed water customers in Naples.
Middleton said the reclaimed water does have some nutritional value for plants as it contains a small amount of nitrogen and phosphorous.
Financially, the alternative water supply program has benefits to the city and to the customers. Not only did the city save millions by implementing this system versus building a new plant, it also saved money by building the ASR wells onsite and extending the treatment capacity of existing water treatment plants indefinitely.
For customers who have the ability to opt in to the system, Middleton said they are paying one-third to one-half of what they were paying for their water previously. There is a connection fee and a base rate charge of $10 per month, plus a cost of $.66 cents per 1,000 gallons used, which is less than the cost for potable water.
Middleton said, “We put a little twist on it — if reclaimed water is available and they don’t connect, they’re still charged a base charge of $10 a month.”
But this charge is only for those users who have the ability to connect or are connected, not other users.
Middleton said other uses for the reclaimed water aside from irrigation is for cooling water for HVAC systems, particularly by government and other large buildings that need a water supply for those systems. Street cleaning operations could also use reclaimed water.
Firefighting is another great use for reclaimed water, and Naples has fire hydrants on its reclaimed system.
“All the fire hydrants on the reclaimed system are painted purple, the international color for reclaimed water — the potable hydrants are painted red,” he said.
All of the city’s facilities are connected to the reclaimed system. Parks, medians and all landscaping at city facilities receive reclaimed water, according to Middleton.
He said because so many elements of Naples’ plan use existing resources, he believes it can be adapted by other Florida cities and possibly beyond the state. He added other cities and towns should compare their water resources to see what is available and come up with a 25-year outlook for their resources.
He does think this is a concern that is spreading inland, and if not right now, it will be in the near future. “I think cities and towns will be moving more and more to reclaimed water,” he said.
Spring Hill, Tenn.
One inland city that has started a reclaimed water program is Spring Hill, which is located 35 miles south of Nashville, Tenn.
Wastewater Treatment Plant Superintendent Travis Massey said there are no city policies in place for reclaimed water. “Right now, we’re only feeding it to the golf course,” Massey said.
The golf course is King’s Creek Golf Course, a privately owned course that opened for public play in December 2005.
Massey said there is a valve before the creek that he can open, sending the water through a gravity flow direct to the golf course. “I watch what the level is in the ponds and open the valve,” he said.
Massey sends water to the golf course daily, and he has a flow meter so he can measure the amount he sends to it. He said by June 18 he had already sent 4.3 million gallons of water to the golf course.
The golf course is adjacent to the wastewater treatment plant, making it easy to do with the gravity flow and valve system. The golf course pays the city $1 annually for receiving this reclaimed water.
A benefit to the city has been reducing the limits of nutrient pounds being released into the creek.
“Long term I hope we can find other resources to give the gray water to — to irrigate the parks or soccer fields or the agricultural center in town; it would have been great if the city could do that,” Massey said but acknowledged to do so would probably carry a big price tag.
As to whether this is something that is spreading to inland states and cities, Massey predicted, “At some point in time, I’m sure everyone will be looking at it.”