Decision Looms for OWASA’s Long-Range Water Supply Plan


By Rachael Rankin

Orange Water and Sewer Authority is in the process of reevaluating its Long-Range Water Supply Plan (LRWSP) to ensure it can meet the community’s water supply demands 50 years into the future.

OWASA’s board of directors is on track to present its stance on the most viable supplemental water source sometime in early 2022, at which point there will be another formal opportunity for community members to voice their opinions.

OWASA Planning and Development Manager Ruth Rouse laid out two options that have made the short-list for consideration: a new water treatment plant or expanding the quarry. The option of renegotiating the mutual aid agreement has been nixed by Cary, and a “deep quarry” option would not be cost effective.

The first option is a full partnership with the City of Durham, Chatham County and Town of Pittsboro for a new water intake and treatment plant on the west side of Jordan Lake. This option is projected to cost around $33.9 million for an assumed estimated yield of 5 million gallons per day (mgd).

Alternatively, OWASA could opt to increase its water supply without diversifying it. The utility is in the process of expanding its Quarry Reservoir, which is refilled from the Cane Creek Reservoir. The expansion should be completed in 2030, at which point between 1.3 and 1.9 billion gallons of the new water storage capacity will be accessible, supplementing the 3.65 billion-gallon capacity of Cane Creek Reservoir, University Lake and the Quarry Reservoir that OWASA currently relies upon.

The expansion is estimated to cost $2.4 million for a total estimated yield of 2.1 mgd and is set to take place regardless of whether the Jordan Lake partnership occurs.

OWASA considered constructing a deep vertical shaft and multi-level pumping gallery in the Quarry Reservoir, potentially providing an additional 1.3 to 1.7 mgd. However, OWASA’s estimates indicate that the deep Quarry Reservoir option is less cost effective than the Jordan Lake option, with a potential cost of either $77.3 million or $35.8 million (depending on transmission infrastructure choices) and does not diversify its water supply.

OWASA could choose to rely on current mutual aid agreements that allow for the purchase of treated drinking water from the Jordan Lake intake jointly owned by the towns of Cary and Apex, which would be supplied through interconnections with Durham. These agreements “don’t guarantee that we could get that water when we needed it,” Rouse said, because other communities may be worse off in times of drought and consequently receive water allocations before OWASA. Developing a new agreement with the Town of Cary, such as paying a minimal cost annually to guarantee access to an allocation from Jordan Lake during non-peak times was considered, but Cary was not interested.

In March, Rouse presented a summary of community feedback about the options to the board. Community members worried that the Jordan Lake option encompassed a larger watershed and thus would have more potential pollutants flowing into it.

Multiple studies have evidenced that the Haw River, which enters Jordan Lake downstream from the intake of the proposed water treatment plant and is in the same watershed, contains concentrations of certain aquatic contaminants that are far above the EPA’s health advisory limits. In particular, the presence of per- and polyfluoroalkyl substances, commonly known as PFAS, is a concern because the EPA has not established a maximum contaminant level (MCL) for drinking water.

This means that water treatment plants in North Carolina are not required to monitor for these substances, and drinking water can potentially contain higher concentrations than the recommended threshold, as has been found in some homes in Pittsboro.

Heather Stapleton, a Duke University professor who has been investigating PFAS levels along the Haw River and in Jordan Lake for the past two years, weighed in.

“The city of Pittsboro pulls their drinking water from the Haw River, and our analysis over time suggests that what’s in the raw tap water is pretty similar to what’s in the Haw River,” Stapleton said. PFAS in Cary and Apex tap water is a little lower than what’s in Jordan Lake, which she attributes to more advanced drinking water treatment processes in the treatment plant Cary and Apex use.

Stapleton also noted that “[there are] a lot of ongoing discussions related to what’s considered a safe level for PFAS in drinking water. Several states in the U.S. have already established MCL values for drinking water, and some of those thresholds set in other states are lower than the levels that we’ve seen in the Haw River and in Jordan Lake, so this has implications for Apex and Cary that pull their drinking water from Jordan Lake.”

Ray DuBose, OWASA’s board chair, guaranteed that comments about PFAS contamination have been heard and are going to be thoroughly considered before a final decision is made. “The water treatment process has to deliver high-quality water to our customers,” he said. “Without regard to the source, the water treatment process will be designed and developed so that the quality of the final product delivered to the customer will be maintained. And OWASA has a long, outstanding record of delivering high-quality water to its customers.”

Longtime community member and former OWASA board member Will Raymond countered that as a community-owned utility “meeting the current N.C. state and EPA standards should be the low bar for OWASA water quality.”

If OWASA moves forward with the Jordan Lake option, Raymond said, ensuring that Orange County customers are provided with high-quality water will not be as simple as it may seem.

Raymond said he believes OWASA will have far less control over the quality of the Jordan Lake water than it currently has over its supply from Cane Creek Reservoir and the Quarry Reservoir. OWASA’s current reservoirs are managed by fewer than 10 governmental units, whereas over 40 governmental units manage the waters discharging into Jordan Lake.

“At one point OWASA collaborated with UNC on testing for pharmaceuticals and other chemicals that are known carcinogens, toxic or otherwise unacceptable,” Raymond said. “That trial was quickly extinguished once it became clear that even our protected sources of water have contaminants OWASA would rather not talk about.”

The Quarry Reservoir option would give OWASA greater control over the watersheds and, thus, what goes into our drinking water, Raymond said. With the Quarry Reservoir option, he said, “we’re not fighting anybody over those resources. OWASA, in this community, will control those water resources completely. There is no negotiating for parts of it, slicing up a vanishing pie.”

He believes that a partnership with the City of Durham, Chatham County, and the Town of Pittsboro will not provide the water quality the community wants, even though regulatory standards will be met. The other utility companies are not community-owned like OWASA and may have even less incentive to implement non-standard technology and processes into the proposed water treatment plant, even though doing so would provide customers with higher-quality water.

Durham and OWASA discharge their treated water into Jordan Lake. And though Raymond said the municipalities do a pretty good job of cleaning it up, he is concerned a new water plant might not test for everything that could go out through it, only the minimum testing is required. Durham and OWASA are not looking for “the hormone pharmaceuticals that are causing frogs to become sterile, that kind of thing,” he said. “I would argue it is the duty of OWASA to be looking for — it should be the duty of all of these, anybody consuming water out of Jordan — to really look at the quality.”

Rouse said the Western Intake partners would look at types of treatment that could address issues of emerging contaminants such as PFAS. The partners have already started collecting data around potential intake sites to make sure that they can treat the water in Jordan Lake, she said, but that “those are types of questions that will be answered more likely in the future in terms of specific design elements.”

Raymond contends not only that the quality of the Jordan Lake water would fall below community expectations, but that going forward with the Jordan Lake intake option could have severe ramifications on the development of rural areas in Orange County.

He points to the Drought Response Operating Protocol, which OWASA rescinded in December. Instead, OWASA incorporated DROP into its Water Shortage Response Plan, which requires the utility to provide the community with notice when mandatory water restrictions are enacted, such as when the Mandatory Stage 1 Shortage threshold of 10 percent is approached.

Meeting notes on OWASA’s website indicate that DROP was rescinded because it placed “self-imposed constraints on our ability to use water from Jordan Lake. … This internal policy limits the effectiveness of each of the Jordan Lake alternatives. For the alternatives where OWASA would participate in the Western Intake and [Water Treatment Plant], OWASA would be making a significant investment in resources that we would only be able to access or use during extreme water shortages. For the alternatives in which we are continuing the use of mutual aid agreements or developing new agreements, we are limiting the conditions under which we can purchase water from our neighboring utilities.”

Raymond, who helped to develop and adopt DROP in 2013, said that the protocol specifically prevented permanent access to Jordan Lake to avoid urban sprawl into rural areas. He believes that by making an investment in Jordan Lake without DROP in place would “require that we violate the rural buffer; we’re going to literally incentivize development just to the south of Chapel Hill and Carrboro, in Chatham County.”

But Rouse said removing DROP from the LRWSP “has nothing to do with how the county and the towns regulate growth.”

Yet the community feedback section in OWASA’s March 11 board meeting notes mention the concern: “Protection of our local water supplies — There was concern that if OWASA started using Jordan Lake as its main water supply source, there would be pressure to back off on the zoning and other watershed protection measures in the Cane Creek Reservoir and University Lake watersheds.”

Development increases demand for water, and advocates of the Jordan Lake option cite concern that the Quarry Reservoir option would not meet demand should there be a prolonged drought. Climate uncertainty is the primary driving mechanism behind their quest to diversify OWASA’s water supply. Yet climate projections indicate that this area should receive roughly the same or more rain in future years, although rainfall may occur more sporadically.

OWASA’s Aug. 13 board meeting notes state: “Given the relatively small drainage area of the Cane Creek Reservoir watershed, which provides the majority of our water storage, … Cane Creek Reservoir could take over a year to refill following a drought, depending on weather patterns. If this occurs, our water supply is at risk. While historic weather conditions indicate the risk is low, the risk may increase as weather patterns become more variable with climate change.”

But Section 4 of the 2013 LRWSP argues otherwise. “[U]nder most conditions — even a recurrence of the 2001-02 drought of record — OWASA’s existing system can meet virtually all of our expected needs for the next 25 years, provided that the 25 percent reduction in water use achieved since 2002 is sustained in the future. Additional water will be needed after 2035, but the amount and timing of those longer-term needs will depend on actual demands at that time.”

Right now, OWASA’s Water Watch indicates that its reservoirs are 100 percent full. Even with no further rainfall, the current supply will last for 650 days.

The final decision for OWASA’s best LRWSP option depends on the community. Rouse and OWASA’s board invite community members to reach out if they have any questions or comments. Board meetings, while virtual, are still open to the public.

The next meeting is scheduled for May 13 at 6 p.m. If you would like a say in the LRWSP update process, OWASA strongly encourages attending.

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