New Reservoir May Be “Inevitable” for Raleigh

Raleigh is projected to run out of water in 20 years, and by 2060 the city will need more than twice the volume of water that it uses today, according to the city’s first Water Resource Assessment and Plan.

In 2007, the city started the process to gain federal approval to dam the Little River; however, the city must first show that no less environmentally damaging practical alternatives are available.

The City Council recently authorized $355,000 to pay Hazen and Sawyer to do just that. That money is in addition to the roughly $6 million spent since 2007 exploring the Little River Reservoir option.

Media credit: City of Raleigh

The Little River Reservoir is estimated to cost $263 million and will extend the water supply by just 10 years. The city already owns all of the land that would be inundated.

“It is going to take a combination of these alternatives,” Waldroup said, “so if the Little River Reservoir is not the selected, preferred project of today, it will be needed for our communities to grow in the future, no doubt.”

The Endangered Species Act, environmental groups, state and federal regulators, and smart growth advocates are all requiring Raleigh to show that it has explored alternatives, implemented efficiency and conservation measures, and completed environmental impact assessments before accepting that the Little River Reservoir is the best option.

The city’s new Water Resource Assessment and Plan offers a comprehensive summary of supply issues and conservation and efficiency efforts.

Water is not just Raleigh’s problem—there is demand for water across the region. Without it, the rate of growth the Triangle is expecting will be difficult to sustain.

The Jordan Lake Partnership, made up of communities around the Triangle, is looking at how to maximize the Jordan Lake water supply.

Raleigh’s recent creation with its eastern Wake County neighbors of a water service area was in part motivated by regional thinking.

Tom Fransen, deputy director of the Division of Water Resources, said the federal government, the U.S. Army Corps of Engineers and the U.S. Fish and Wildlife Service will look for the least environmentally damaging options.

“They are going to look at things like, is there a regional solution? Is there surplus water that a neighbor has where an interconnection might make sense versus [building] a whole new reservoir?” he said.

Raleigh’s Water Predicament
Raleigh’s Water Utility Transition Advisory Taskforce, known by the acronym WUTAT and pronounced woo-TAT, is a group of political, industrial and university representatives. The task force recommended that the city’s public utilities department produce a Water Resources Assessment and Plan to analyze long-term water supply and demand, promote conservation, educate customers, and seek a diverse set of water supplies.

The plan looks ahead 50 years at supply and demand, new supplies, efficiency and conservation, storm water and wastewater, regional cooperation, and practices now unfeasible or illegal that might later become options. The report summarizes for city council members and residents the status and future of the city’s water supply.

Raleigh Water Projections

All values in million gallons per day 2011 2020 2030 2040 2050 2060
Surface Water Supply 77.3 77.3 77.3 77.3 77.3 77.3
Future Supplies (Little River Reservoir) 0.0 0.0 13.8 13.8 13.8 13.8
Total Available Supply 77.3 77.3 91.1 91.1 91.1 91.1
Demand 51.0 64.4 78.2 91.3 102.7 115.0
Need 0 .2 11.6 23.9

 

Waldroup said that new water is hard to acquire "either because of the monetary value involved or because there are multiple parties that have objections to it or there is a significant environmental impact or a significant social impact.”

If current projections are correct, the city needs more water by 2030.

The city reviewed 25 options, including piping water from as far away as the coast or Kerr Lake. Hazen and Sawyer will study the three most likely options other than Little River: extracting more water directly from Falls Lake, from below the Falls Lake dam, or from the Neuse River near the Johnston/Wake County line.

Because all three options rely on the Neuse, “if one is chosen, it makes the other two unlikely,” Waldroup said.

The Tar River Spiny Mussel is on the endangered species list. Source: U.S. Fish and Wildlife Service.

Each of the choices will need to address the impact to endangered species. The Little River is home to two endangered species, the Tar River Spiny Mussel and Dwarf Wedge Mussel. Five more species that call the watershed home are on the federal list for consideration, Waldroup said.

The Atlantic Sturgeon was listed earlier this year—a species that exists in the Neuse from the coast all the way upstream to the dam.

Potential Water Sources
The city will need multiple sources in the next 50 years to meet the predicted 38 million gallons per day demand. Raleigh already can draw up to 66 million gallons per day from Falls Lake and 11 million gallons from the Swift Creek system (lakes Benson and Wheeler).

Drawing more water from Falls Lake, the leading alternative to the Little River Reservoir, seems like an obvious choice, but it requires the approval of the United States Army Corps of Engineers—the organization that manages the space above the dam for flood control, water quality preservation, and water supply and sediment storage.

Raleigh would like to convert some of the water quality portion into supply.

Source: City of Raleigh 2012 Water Resource Assessment and Plan

“It may take three years and three million dollars just to approve the project,” Waldroup said.

The city would be required to study the impact on downstream organisms and water quality in the lake.

During the Falls Lake Nutrient Management Rules creation process in 2009, the data about water quality in the lake was widely disputed. If Raleigh were to withdraw more water from the lake, it could affect the ecosystem and perhaps degrade the water quality further—making the water more difficult and expensive to treat and making the efforts of upstream communities to clean up their discharge seem futile.

The lake would be lower more days per year, disrupting recreational uses and the lake’s ability to serve as a drought buffer.

Another option is to extract water directly from the Neuse River below the dam. A nearby quarry would be used to store water as a buffer for drought and periods of peak use. However, that quarry is still active and privately owned.

The third option is to insert an intake in the Neuse River near the Wake and Johnston County line. There is no storage capacity with this option.

Each choice takes more water directly from the Neuse and, like all of the options, requires state and federal approvals.

Other Options
The Water Resource Assessment and Plan also looks at innovative water supply options. The capture and reuse of stormwater is considered but is rejected as too expensive.

Reusing treated wastewater is another option. It has been done in other places such as San Diego, the Philippines, and Gwinnett County, GA.

In practice wastewater is usually used indirectly—discharged into a reservoir, river or aquifer before being used as a raw water source some distance away. The practice is prohibited in the state of North Carolina, even though nearly half of the Neuse River below Raleigh’s wastewater treatment plant is treated wastewater.

Waldroup said the city council has asked public utilities to request the General Assembly’s permission to complete a pilot study to re-use water in one of its reservoirs.

The idea is politically unpleasant—many almost instinctively recoil from the notion of reusing treated wastewater. However, Waldroup said, the city of “San Diego figured out that the water they pull from the Colorado River has been through something like 350 wastewater treatment plants before it gets to them.”

San Diego has begun recycling its wastewater.

If Raleigh receives approval for the pilot, it will be the first time the practice has been allowed in North Carolina.

Another option is to use water from Jordan or Kerr Lake; however, the state strictly regulates the transfer of water between watersheds. Fransen estimates that it would cost a million dollars and take three to five years of study just to receive permission to begin the permitting and infrastructure building process for such an endeavor.

And regional neighbors could sue to prevent the transfer.

Little River Wetlands. Photo by American Rivers.

The assessment and plan considers efficiency and conservation as a new water source. Raleigh residents have begun to use water more wisely, Waldroup said.

“In 2007, the city used 51 million gallons per day. In 2012, the city used 51 million gallons per day, yet we added between 20-30 thousand people in our service areas.”

Karen Rindge, executive director of WakeUP Wake County, asks “have we done everything with water efficiency that we could be doing and water reuse? Have we really looked at using other ways to capture rain water such as large cisterns, and incentivizing those?”

Indeed, cisterns prevent rain from washing nutrients and sediment into local waters and serve as a source for irrigation. The Whole Foods built in 2011 off of Six Forks Road in north Raleigh was built with an 11,000-gallon cistern to capture rain water to irrigate lawns and flush toilets.

The plan shows that the city considered updating the fixture-replacement incentive from the 1994 water efficiency standard to the newer EPA WaterSense standard, but does not recommend it, implying that it would be culturally and socially unacceptable at this time. Waldroup added that state building codes prevent the city from mandating it.

The newer WaterSense standard requires 20 percent more efficient fixtures than the 1994 standard—the 2-gallon-per-minute shower head recommended in 1994 is reduced to 1.6 gallons per minute under the WaterSense rule. A 20 percent efficiency gain across the city would stretch Raleigh’s water supply another decade.

“In the end we may need to do the Little River project, but the environmental impact is going to be significant. It is one of the last pristine rivers in the area.” Rindge said. “All that land they bought for it would also make a really nice park.”

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