May 9, 2016: SolarBee-Minus

North Carolina’s giving up on Solar Bees in Jordan Lake after they proved ineffective…just as Jeff (and scientists in general) predicted they would.

Help Clean Jordan Lake

That piece of litter you saw on the side of the road earlier today?

Sooner or later, that discarded trash is going to make its way into the water. And a lot of that water flows into Jordan Lake – which makes for a pretty big mess.

Seven years ago, Fran DiGiano co-founded the group Clean Jordan Lake to help address the growing issue – and since then, he’s organized thousands of volunteers to collect tons and tons and tons of trash. More than 4,000 volunteers and about 104 tons, to be precise – totaling more than 10,000 garbage bags. (And nearly 4,000 discarded tires.)

DiGiano says they’ve managed to catch up with all the accumulated garbage from years past, but since people continue to litter, cleaning the lake will always be an ongoing process.

Want to help? This coming Saturday, March 19, Clean Jordan Lake is holding its annual spring cleanup, from 9 am to 1 pm. Volunteers will meet at the New Hope Overlook access to Jordan State Recreation Area off Pea Ridge Road in New Hill. (That’s just north of US-1 a little southeast of Pittsboro.) Lunch will be served and there will be a trash treasure hunt (really!) with prizes.

Fran DiGiano spoke with WCHL’s Aaron Keck this week.


To learn more information about the spring cleanup and to volunteer, visit

Can We Start Protecting Jordan Lake Now?

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One of my motivations for writing this column is my hope that, at least in some small way, I am helping to inject more science into public policy decisions. Maintaining this hope can be especially challenging at times. The “experiment” to clean up Jordan Lake with larger mixers known as Solar Bees presents one of those challenges. Allow me to walk you through my frustration on this ill-fated and poorly-reasoned project.

As local readers will likely know, Jordan Lake provides drinking water for over 300,000 people including the city of Raleigh. In addition, it provides fishing, boating, and swimming opportunities for thousands of people and a place to live for fish, birds, and a variety of other wildlife. For many years now, Jordan Lake has been consistently failing water quality standards for chlorophyll. Before discussing options to address this problem, let’s review how a lake comes to fail chlorophyll standards and why that is a problem.

Chlorophyll is the molecule that makes plants green and that captures sunlight for photosynthesis. Chlorophyll in lake water comes primarily from algae, so a lake with too much chlorophyll has too much algae, a situation often referred to as an algae bloom. Algae blooms occur when a body of water accumulates high levels of nitrogen and phosphorous containing nutrients. These nutrients enter the watershed from run-off of fertilizers, primarily from residential and commercial rather than agricultural locations(1), and from the outflow of municipal wastewater facilities.(2)

Excess algae in lakes and other bodies of water can cause several problems. Some species of algae produce chemicals that are toxic to humans. This can cause problems both for swimmers and can also threaten water quality if the lake is used as a drinking water reservoir. Lakes with an algae bloom are aesthetically displeasing and often emit foul odors. Further, excess algae in a lake also lead to reductions in dissolved oxygen concentration, a subject that I expand on below.

Algae tend to live on or near to the surface of lakes where they can receive sufficient sunlight. They have short life spans and fall to the bottom of the lake when they die. Bacteria that live at the bottom particularly enjoy dead algae as food and consume dissolved oxygen in the process of eating it. Thus, a lake with excess algae on the surface rapidly losses dissolved oxygen. If the oxygen concentration drops too low, fish and other aquatic life suffocate and die.

In analogous manner to most any other pollutant, the problem of excess nutrient accumulation is best addressed by reducing the introduction of these nutrients at their sources. It is important to note that this is a scientific rather than a political statement. Pollutants are concentrated at their source and become diluted when allowed to escape. The laws of thermodynamics tell us that the energy one needs to expend to collect and remove a dilute pollutant far exceed that required to manage a concentrated pollutant. Therefore the best and most energy efficient manner to protect Jordan Lake is to make improvements at wastewater treatment plants and to improve regulations for residential and commercial development to limit run off. These approaches would raise the cost of wastewater treatment and real estate development, so it should not surprise you that some people and groups are opposed to making these changes.

Over many years all of Jordan Lake’s stakeholders, developers, citizens, legislators, and the like, negotiated a set of regulations and standards to reduce the flow of nutrients into Jordan Lake’s watershed with the approaches I outlined in the paragraph above. Theses rules set to take effect in 2009, nearly seven years ago. Since then, parties opposed these rules have successfully lobbied for successive delays and the regulations are still not being applied and enforced. The most recent delay was granted to allow this Solar Bee “experiment” to be attempted.

  • Solar Bees are large, floating solar-powered mixers Solar Bee. In early 2014, the North Carolina General Assembly approved yet another delay in the implementation of the Jordan Lake rules in order to try to use them to solve the problem instead. The intent of the mixers is to push nutrients entering the lake to lower depths before they can fertilize algae growth near the surface.   In addition, the mixers are supposed to disperse the algae such that the lake looks better. There is such a long list of flaws in this plan that I think I decided to resort to bullet points to detail them.
  • Mixing works best in regular, nearly circular geometries. To the extent there are irregularities in the geometry, poorly-mixed pockets inevitably occur. Have a look at this map of Jordan Lake. Jordan Lake You can’t get much more irregular than that.   The idea that you could mix up Jordan Lake in some effective fashion without essentially blanketing its surface with mixers requires both a total disregard for engineering principles as well as a healthy measure of hubris. I supposed this point seems a bit nuanced to some, but it really gets under my skin. Legislators can see North Carolina State University and its top-notch engineering school from the rooftop of the General Assembly building. I’m sure they’d be happy to help.
  • Even if the Solar Bees worked, nutrients entering the lake would accumulate over time in the sediment on the bottom of the lake.   These nutrients would then bide their time until a storm or flood resuspended them, thereby bringing about the mother of all algae blooms.
  • Lastly, even if the mixers worked as their supporters hope, since they are only in the lake, they would only protect the lake. This would allow nutrients to continue to flow into every other stream, river, pond, or marsh in the rest of the watershed allowing for algae to bloom everywhere else.

When the Solar Bee project was being considered in early 2014, I delivered this commentary on 97.9 FM/1360 AM WCHL. Have a listen if you want to get a better sense of my frustration.

Last month a report was issued on the effectiveness of the Solar Bee project after then had been spinning about for a year. As could have been and was predicted, there have been no improvements in water quality in Jordan Lake. This hopeless project should be stopped and the Jordan Lake rules intended to be implemented in 2009 should be put into place as soon as possible.

Sadly, that is not the likely outcome. The Solar Bee project has been given a 4 year time period to demonstrate water quality improvements. This extended timeline is yet another example of how this project is ignoring basic science. There are no aspects of the Solar Bee technology that would take multiple years to take effect. Nevertheless, it appears that we will delay another 3 years before starting to fix this problem. That is a shame.

Jeff Danner discussed this column with Aaron Keck on WCHL.


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  1. Often when the run off of fertilizers into watersheds is discussed, farms a listed as a key source. While there is certainly some run off of nutrients from farms, farmers usually go to great lengths to minimize this. They are paying for the fertilizer and manage their lands and operations to keep them in place. The over application and misapplication of fertilizer to residential and commercial lawns is a larger contributor to the problem.
  2. I am currently serving on the Board of Directors of the Orange Water and Sewer Authority, the utility that provides drinking water and waste water treatment services to the cities of Chapel Hill and Carrboro, North Carolina, the University of North Carolina, and some surrounding areas of Orange County. The outflow of the waster water treatment plant is in the Jordan Lake watershed. As is the case with this and all of my columns, the opinions contained within represent my opinion and are not a statement of the Board.

Environmental Group Wants To Bring Back Jordan Lake Protection Rules

Jordan Lake and the Haw River are two bodies of water that impact our area and are at the center of a debate between conservationists and state lawmakers. The argument is about how to reduce pollution in Jordan Lake, either by enforcing pollution controls throughout the watershed or by using a new method whose effectiveness some question.

Elaine Chiosso, the Haw Riverkeeper for the Haw River Assembly, listened in as a state legislative research committee on Jordan Lake met Wednesday, taking public comment on the issue.

She is one of many environmentalists who are urging lawmakers to bring back the “Jordan Lake Rules,” which were designed to protect the lake and its watershed by limiting nutrient and pollutant runoff.

“Our state has gone backwards at the task of trying to restore this river and Jordan Lake,” she said.

The Haw River flows 110 miles from the north-central Piedmont region of the state, to the Jordan Lake Reservoir, and into the Cape Fear River in south Chatham County.

Chiosso said she was “outraged” when the General Assembly decided last summer to put the Jordan Lake Rules on hold for three years, before many of the measures could be implemented.

Some said the rules which were developed in 2009 would cost developers hundreds of thousands of dollars to meet the standards.

What pollution flows into the Haw River, Chiosso said, will eventually make its way downstream into Jordan Lake, the source of drinking water for much of the Triangle.

“Really the biggest impacts on Jordan Lake come from people that are farther away. It is harder to make that case,” Chiosso said.

As alternative measure, the state went forward with installing SolarBee aerator pumps in the lake, which some said would be a cheaper way to keep the lake clean.

The giant pumps will circulate the water near the surface, with the intention of reducing algae blooms.

Chiosso said that based on the information discussed Wednesday, she was not convinced that there are solid parameters in place to determine if the pumps are effective.

“These SolarBees, by churning up the water, keep algae from growing, but it doesn’t stop any of the pollution that is in that water. Really all your are doing is sending that water in Jordan Lake as it goes downstream. Jordan Lake is not a closed system. It is the Haw River and it keeps going on down to meet the Cape Fear. You are just down into the Cape Fear River.”

By rolling back the rules designed to address water pollution, Chiosso said many ague that this puts the state in conflict with the U.S. Environmental Protection Agency and the Clean Water Act.

Last week, the Haw River made it on the top 10 list of “America’s Most Endangered Rivers Of 2014,” which was compiled by the environmental group, American Rivers.

“Our best hope right now on getting the Jordan Lake Rules back on track [is that] we need people to be telling the legislature that this is unacceptable. Just because they just said that they are probably not going to talk about it during this session, if there were enough pressure, they might change their minds about that.”

Chiosso added that she was disappointed, but “not surprised” that state leaders indicated Wednesday that they will not revisit the issue during the legislative session in May.

Giant Pumps To Reduce Algae In Jordan Lake, Some Question

CHAPEL HILL – As the state prepares to move forward with a trial method to reduce nutrient pollution in Jordan Lake, some are questioning the logic behind the costly technology. WCHL’s Resident science expert Jeff Danner says the aerator pumps will not be an adequate solution, but rather a temporary fix instead of managing stormwater run-off upstream.

“If we really want to have good water here over the next several decades, we just need to manage our stormwater and just not let pollutants reach our drinking source,” Danner says.

North Carolina’s Department of Environment and Natural Resources is preparing to sign a $1.3 million contract with the Medora Corporation, the maker of the SolarBee, according to WRAL News.

SolarBees are solar-powered pumps that circulate the water near a lake’s surface, intended to reduce blue-green algae blooms.

About three-dozen of the pumps will be place in the lake by April 1.

Danner says that though there are positive aspects to the pumps, he believes that pollution controls upstream are the best way to prevent phosphorus and other nutrients from reaching Jordan Lake, the source of drinking water for much of the Triangle.

“By circulating the water, you can add some oxygen back in, and also by mixing the water, you shift the algae population from the surface. It’s not as though the circulation is without benefit, but what you need to do is compare that to what our plan was in the first place, which was to stop the stormwater run-off and not get the nutrients in the water.”

Environmental advocates have argued for years that Jordan Lake has problems with pollution because it’s fed by streams and tributaries that carry contaminants from urban areas.

Danner explains that warm water in combination with contaminants, particularly those which contain phosphorus, can cause algae blooms.

When a lake accumulates too much blue/green algae on the surface, it can make the water smell or taste badly. It can also create toxicity in the water that can cause people to become ill.

“The only reason that algae is bad for a lake is when you have a lot of algae, it will die and fall to the bottom of the lake where it fuels the population boom in bacteria that eat the dead algae, and that will use up the oxygen in the lake,” he says.

When the dissolved oxygen drops, fish populations begin to die.

Danner says the pumps will likely make Jordan Lake look better for a short period of time but will not be the most viable option.

“Consider the irony of this plan—we would allow the nutrients to get to the lake and then we would be treating it with circulating pumps. Well, that is exactly what happens in a waste water treatment plant and I am not so sure people want their drinking source to be set up like a waste water treatment plant.”

Recently there’s been a debate raging between those who champion environmental protection standards to limit run-off into Jordan Lake, and those who say the rules are too stringent and will negatively impact developers.

“One thing that is missing from the plans with pumps is that all of those stormwater control systems that would prevent the nutrient run-off would also limit the amount of other pollutants that would get into out water supply, like oils and other pollution on the ground that gets washed into our lake,” Danner says. “The same systems that would stop the phosphorus from getting there would stop these other pollutants from reaching the lake, which is another net benefit for your water source.”

The contract between North Carolina’s Department of Environment and Natural Resources and Medora is for a two-year lease on the pumps with an option to buy them later, as reported by multiple news outlets. If the SolarBees prove to be successful, the State will consider purchasing additional devices.

Preston Development Looking To Expand Into Pittsboro

PITTSBORO – Preston Development INC. is planning a new project for Pittsboro called Chatham Park.

The new project would be a long process taking 30-40 years, but could bring many new aspects to the town like medical facilities, parks, trails, houses, and businesses.  Consulting Planner for Chatham Park, Philip Culpepper, says that Pittsboro and the people there will not be left out of the project.

“We will be a part of Pittsboro,” Culpepper says. “We’ve already annexed portions of the property into Pittsboro. We consider Pittsboro, its historic downtown, and the people of Pittsboro an integral part of what we are trying to do.” Culpepper said.

Several developments in Chatham County like Briar Chapel, Powell Place, and Westmoore have tried to blend businesses with housing, but have had little success.  Culpepper says that they have a different plan to bring in business and that they will not focus on retail like these other developments.

“We’re looking at more of broader range, of not only retail, but medical facilities, light industries, office parks, things like that,” says Culpepper. “So it’s a much broader range and we’re already seeing the demand. We anticipate building a medical office facility here very shortly.”

Currently Preston has several projects ranging across the state.  When asked why Pittsboro, Culpepper says it seemed like the next big area for the Triangle.

“Seeing it as the next logical location for development to occur,” Culpepper says. “Wake County, a lot of development has taken place to the west side of Wake County. Jordan Lake comes in, realizing the demand was going to be there, realizing that we wanted to put a quality project there so that the demand could come into a quality development rather than being scattered across the county.”

Culpepper has worked with Pittsboro commissioners for the past eight years on planning this project and has faced almost no opposition. A few people have complained that the town will have to provide the infrastructure for the development.  One of the owners of Preston Development, Tim Smith, says that this will not be a problem because the company is planning on building the entire infrastructure themselves and possibly giving it over to the Town in the future.

“We’re not asking the citizens to pay for anything,” Smith says. “We’re going to pay for our own water lines, our own sewers, own sewer plants, and we going to generate enough tax revenue to go back to pay for anything that the Town would require to give us like fire, police, and all that; so we’re paying for everything. This project will not cost the citizen of Pittsboro one cent, not one cent.”

Preston development is also a member of the “Clean Tech” cluster, a world-leading user of energy saving devices.  Smith says that as a member of the “Clean Tech” cluster the developers plan on using the green technology from the RTP area to make the development as new and modern as possible.

“Everything that we can possibly do, everything that’s new we want to use it,” Smith says. “If something comes out next year that’s better, we intend to use it. So we intend to use everything that’s available to us that’s why we’re a member of this Clean Tech cluster. They’re going to provide us with all their expertise and use our project as a model demonstration project for the world, so we’ll be a world demonstration project for all the newest things that come out.”

The Chatham Park development may grow past the current 7,120 acres of land that are already owned.  Smith says he hopes that in 40 years he can look at the development and be proud of everything that they achieved.  Smith also says they want to work with local contractors and businesses when developing Chatham Park to include the community in the development.

Below is a map of the proposed site for Chatham Park in relation to Pittsboro.  On Saturday, the Town Commissioners are having a meeting to discuss some aspects of Chatham Park with their staff.

8.14 news2chatham raleigh.indd

Battle Over Jordan Lake Anti-Pollution Rules Continues

CHAPEL HILL – A bill is now heading to the NC House of Representatives that seeks to repeal the state’s water protection rules to lessen pollution and run-off into Jordan Lake—the water source for much of the Triangle. It’s already passed in the Senate and now local conservation  groups are speaking out against the bill.

“That’s pie in the sky. That is magical thinking. There’s no other solution for improving the water quality than to stop the pollution of Jordan Lake; we have to prevent the pollution from getting into the water,” said Olga Grlic, co-chair of the Orange-Chatham County Sierra Club.

Grlic , a resident of Chapel Hill, attended a press conference Friday—organized by the state chapter of the Sierra Club. Its goal was to raise awareness about the effects this legislation might have on Jordan Lake.

Other environmental groups like Environment North Carolina and the Haw River Assembly were in attendance.

“There’s also an overload of information so anything we can do to let people now what is going on is bound to wake people up and encourage them to contact their representatives,” Grlic said.

Jordan Lake currently provides water to about 250,000 people in our area and Grlic says that number will likely double in the next ten years.

Environmental advocates have argued that Jordan Lake has problems with pollution because it’s fed by streams and tributaries that carry contaminants from urban areas.

Another issue is that  fertilizer washes into to the lake from people’s yards. This causes algae blooms that bacteria will consume– subsequently causing a rise in the bacteria population. The high bacteria population then consumes dissolved oxygen in the water faster than it can be replenished by new oxygen dissolving in from the air. When the dissolved oxygen drops and fish populations begin to die– as local science expert Jeff Danner explained.

Grlic says Jordan Lake is already on the verge of not living up to federal regulations.

“I think a lot of the bills have gone through at such a crazy speed that there hasn’t been enough room for consultation,” Grlic said.

Sponsors for the bill have said the current rules, which were put into place in 2009, are costing developers hundreds of thousands of dollars and need to be changed. Grlic says if these rules are repealed—the situation will get worse.

“Whenever roads are paved—these impervious surfaces cause run-off bringing dirt and bits of oil,” Grlic said. “Fertilizer from lawns also gets washed into the lake.”

NC Senator Ellie Kinnaird (Dem.), who represents Orange and Chatham Counties, has also spoken out against the bill. She says environmental regulations being swept aside by the General Assembly.