Recent rain has eased drought conditions across much of North Carolina, but experts say the effects of months of dry weather don’t disappear overnight.
As lakes and groundwater levels drop, water temperatures can rise, algae can flourish and, in some cases, contaminants can become more concentrated because there’s less water to dilute them. Then, when heavy rain returns, runoff can wash sediment and other pollutants into drinking water sources.
For public water systems, those changes happen largely behind the scenes. Operators monitor water quality daily and adjust treatment before water reaches customers’ taps. For homeowners with private wells, that responsibility largely falls on them.
Laura McKelvey has been thinking about what might be happening beneath the surface.
The Chatham County homeowner has relied on a private well for more than 30 years. During this summer’s drought, she noticed the water pressure dropping — something she hadn’t experienced during previous dry spells.
“It’s scary,” McKelvey said. “I worry because the less water you have, the higher the concentration of contaminants can become.”
McKelvey, a retired Environmental Protection Agency employee, said the drought also underscored another concern: rapid development across the region. New neighborhoods, private wells and future data centers all draw from finite groundwater supplies, while more development can also mean more potential sources of pollution.
She decided it was time to test her well for the first time in several years.
“As long as they turn on the tap and it’s not brown and it doesn’t smell bad, people just assume our water is good,” McKelvey said. “That’s not necessarily a safe assumption anymore.”
What drought can mean for private wells
Ian Land, co-owner of Triangle-based Aqua Solve NC, said drought can lower groundwater levels, stir up sediment and change water quality, particularly in lower-yield wells.
His company has received calls from homeowners whose wells suddenly became discolored or even ran dry after years without problems.
“People who’ve lived on a well for 20 years and never had a water issue, all of a sudden they’re like, ‘Why is my water orange?'” Land said.
Land recommends homeowners test private wells at least once a year and sooner if they notice changes in color, odor, taste or water pressure.
Many local health departments offer free or low-cost testing for common contaminants, and certified laboratories can analyze water for contaminants such as PFAS and heavy metals.
During a well test observed by WRAL at a Raleigh home, Aqua Solve found elevated nitrate levels and more acidic water than in a sample collected around the same time last year. Experts cautioned that a single comparison cannot determine whether drought caused the changes, but said it underscores the importance of routine testing.
McKelvey has already invested in treatment after elevated iron in her well stained white laundry years ago. She also installed a reverse-osmosis filter on her kitchen tap because of concerns about contaminants in her drinking water, but those systems don’t solve every concern.
“Reverse osmosis does pull out the PFAS, but I only have it on my drinking water tap,” McKelvey said. “Showers, laundry, cleaning — we’re still exposed to it. If I could afford to do a whole-house system, I would, but I can’t afford to do that at this point.”
Water experts say the right filtration system depends on what’s actually in a home’s water, making testing the first step before investing in treatment.
Many well owners don’t realize they’re responsible for monitoring their own drinking water.
“I don’t think there’s a lot of good outreach to the community on well safety,” McKelvey said. “I knew because I worked for the EPA, many of my neighbors are in the dark about pollutants in our community. It would be good if there was more communication.”
Utilities adjust treatment as conditions change
Public water utilities across central North Carolina told WRAL they continuously monitor changing water quality and adjust treatment as conditions evolve.
At Raleigh Water, Water Jesus Edward Buchan said the drought actually improved one aspect of Falls Lake’s water quality.
Buchan said lower water levels can reduce dilution, potentially allowing some contaminants to become more concentrated, particularly in smaller reservoirs.
Heavy rain after a drought can create a different challenge by washing sediment and debris into reservoirs and changing the water utilities must treat. During the driest part of the drought, Buchan said Falls Lake actually became noticeably clearer because there was little rainfall to stir up sediment.
Those shifting conditions are also changing how utilities prepare for the future. Buchan said Raleigh Water built climate change into its drought planning more than a decade ago and plans to reevaluate its response after this year’s drought.
“The current thinking is this area in general will be getting wetter as the years go on, but conversely, when we do have a drought, it can be more intense, last longer and be drier,” Buchan said. “It’s something we’re having to consider.”
At the Orange Water and Sewer Authority, operators have been closely watching water temperatures, algae, conductivity, dissolved solids and PFAS as reservoir levels declined.
“We’re looking toward a multi-year response to the drought,” said Allison Spinelli, OWASA’s director of water resources. “It takes a long time for water systems to actually recover.”
OWASA has also adjusted how it draws water from its two reservoirs. Because University Lake dropped faster than Cane Creek Reservoir, the utility shifted from its typical blend to pull more water from Cane Creek. That required operators to increase powdered activated carbon because Cane Creek contains higher PFAS levels.
Spinelli said utilities routinely adjust treatment by changing chemical doses and continuously testing water quality before it enters the distribution system.
“The mix of raw water coming into the facility plays a significant role in how we manage what chemicals we’re doing, how much we’re adding and any of the changes we need to make to adjust for that water quality change,” Spinelli said.
After recent rain, OWASA’s reservoirs recovered about 5% of their storage.
“Every little bit of water that we can gain back is a big deal for us right now,” Spinelli said.
The drought has also prompted regional cooperation. OWASA has been supplying water to Durham, whose reservoir levels fell more sharply earlier this summer.
Joe Lunne, a spokesperson for Durham’s Department of Water Management, said recent rainfall has increased its supply of easily accessible water from 83 days to 134 days, while supplemental water from Jordan Lake, OWASA and Teer Quarry has helped maintain supplies. The utility said it has continued meeting all state and federal drinking water standards throughout the drought and has not needed to change its treatment strategy despite adding new water sources.
Some systems also experienced noticeable changes in the water customers could taste.
In June, Hillsborough reported that hot temperatures, low river flows and algae growth in the Eno River caused earthy or musty flavors and odors in drinking water. The town increased the amount of carbon used during treatment and emphasized that the water remained safe to drink.
Even as the latest drought map shows improving conditions, utilities say recovery will take time.
For customers on public water, that means treatment plants will continue adapting to changing conditions behind the scenes. For private well owners, experts say the best first step is knowing what’s in the water coming out of the tap.