WILLISTON, N.D. – Williston’s sewage lagoon system can’t handle the city’s expanding population and concerns are growing about the impact it’s having on the backwaters of the Missouri River and headwaters of Lake Sakakawea.
Six fish kills have been reported this year in or near a marsh where Williston discharges 19 million gallons of treated wastewater each week.
Stakeholders differ in how much blame they assign the city for the fish die-offs, or whether other factors contributed to their deaths. But water quality tests confirm that levels of ammonia where wastewater empties into the marsh have been toxic to fish.
Before the city’s population exploded, the city discharged wastewater from the lagoons into the marsh twice a year – once in the fall, and once in the spring, allowing a longer timespan for treatment to occur.
Now the lagoons are always full, forcing the city to empty wastewater into the marsh Monday through Friday.
City Public Works Director David Tuan says Williston can’t slow down the amount of wastewater it receives, and the best solution is fast-tracking a $105 million wastewater treatment plant it is building.
The city is spending more than $1 million extra to get a portion of the plant operational this fall, with it expected to be fully complete in 2017, Tuan said.
Until the new facility is operational, North Dakota Game and Fish Department Northwest Fisheries District Supervisor Fred Ryckman said he expects more fish kills in the marsh, and he worries about the long-term impact to the environment.
“This marsh is going to be so full of sewage and wastewater contamination and nutrients,” Ryckman said. “That marsh will be affected long after the city’s not discharging nearly as much stuff into it anymore.”
The situation is a side-effect of the Bakken oil boom in Williston, where rapid growth has forced the city to undertake multiple infrastructure projects at once and take on more than $200 million in debt.
Williston Mayor Howard Klug said if the state had returned oil tax revenue to Oil Patch communities sooner, the city could have addressed major infrastructure projects earlier.
“We’d already be done with all these projects,” Klug said.
Randy Miller of Williston, a licensed bait vendor who traps minnows and has worked around the marsh for 20 years, has tried to draw attention to the conditions in the marsh he sees steadily worsening.
Miller wrote a letter this spring to a U.S. Army Corps of Engineers official and the Friends of Lake Sakakawea after repeated fish kills prompted him to stop trapping minnows in the marsh.
“My biggest concern is what is being pumped across the levee and into the Missouri River and Lake Sakakawea. … The oil boom in North Dakota is starting to take its toll on our water environment and our wildlife,” Miller wrote.
Responding to rapid growth
Williston’s wastewater treatment system, which dates back to the 1970s, is a lagoon system designed for a population of 10,000 to 15,000 people, Tuan said.
“Lagoons are great for smaller towns where there isn’t a lot of growth,” Tuan said. “But as the city has grown very rapidly, it’s quickly overtaken our ability to treat all of that waste.”
North Dakota’s rapid oil development has pushed Williston to the top of a U.S. Census ranking as the fastest-growing city of its size in the nation for each of the past four years.
The 2010 Census put Williston’s population at just under 15,000. But by 2014, an estimated 31,000 people were living and working in the city, according to a North Dakota State University analysis of Williston’s service population.
The city’s service population is projected to be 49,000 by 2019.
Instead of discharging twice a year, the city now needs to discharge about 3.85 million gallons of wastewater each weekday, with a target of not exceeding 19 million gallons per week, said Gina Mottl, wastewater treatment superintendent.
In addition to handling more wastewater, the city has seen more industries dumping chemicals and new restaurants and other businesses disposing of fats, oils and greases into the system.
“All that kind of stuff that taxes your system quite a bit,” Tuan said.
Williston used to accept waste from crew camps, rural subdivisions and other portable toilets, but quit that in 2013 because it was an extra burden on the system, Tuan said.
Other steps the city has taken in response to the demand include adding chemicals to the water and more aeration equipment to speed up the treatment process, Tuan said.
The city also spent $7.5 million on a temporary plant while the new wastewater treatment plant was being developed, he said. But the temporary plant has not worked out as intended.
That facility includes a pipeline allowing the city to release treated wastewater directly into the backwaters of the Missouri without having an impact on the marsh.
The pipeline was used for a short time but has been offline since May 2014 after a fish kill in the discharge area.
The Corps of Engineers, which owns and operates the marsh for flood control, identified hundreds of dead game fish, including northern pike and walleye, over a span of a few days.
The North Dakota Department of Health, which regulates the city’s wastewater discharges, issued Williston a notice of apparent noncompliance and attributed the fish kill to a lack of ammonia treatment in the city’s wastewater.
“We feel that was definitely related to their wastewater discharge,” said Karl Rockeman, director of the Division of Water Quality.
After that incident, the city and the state health department decided together that the temporary plant was providing even less ammonia treatment and discharging through the marsh was the “least damaging option,” Rockeman said.
The equipment in the plant is still being used but not to the level it was intended, Tuan said, and it will be incorporated into the permanent wastewater plant.
Cause of fish kills debated
One other fish kill was reported in 2014 and six fish kills have been reported between March and the end of May in that area, Rockeman said. Most incidents involved dead minnows reported in the marsh, but one other incident involved game fish in the Missouri River backwaters.
On March 16, the Corps documented the dead fish as primarily carp, as well as northern pike, sucker and channel catfish.
The U.S. Fish and Wildlife Service documented 31 dead fish and captured 12 live fathead minnows for analysis, said Ryan Moehring, public affairs specialist.
“What we learned is fluid changes in the gills, kidneys and livers indicated that there’s likely some sort of acute water quality issue causing fish mortality,” Moehring said.
City and state health department officials say there are no tests that conclusively attribute the other fish kills to the city’s wastewater. Naturally occurring factors, such as the amount of of oxygen in the marsh, could contribute to the deaths, Rockeman said.
The marsh also is where a majority of Williston’s stormwater runoff ends up, and that could contain pollutants, fertilizers or other chemicals, Tuan said.
“I think there are a lot of other impacts that people aren’t giving enough credit to,” Tuan said. “They’re inclined to point the finger at us. But there are a lot of other things that are happening that I don’t think people are looking closely enough at.”
Both Ryckman, with Game and Fish, and Corps officials attribute the fish kills to high ammonia concentrations from the city’s wastewater.
“We’re not saying fish don’t die or wildlife don’t die because of natural reasons,” said Tim Gouger, contingency program manager for the Corps. “That does happen. But it’s also hard to ignore that there are acute toxic levels of ammonia in the marsh and sometimes in other areas, and there’s fish kills in proximity to those things.”
During this past year, North Dakota had virtually no other fish kills in the winter or during spring conditions when ice melted, Ryckman said.
“We haven’t had any problems with fish kills other than the situation in Williston,” Ryckman said. “It’s not something that’s widespread. It’s somewhat unique to that area.”
At times, the fish kills have occurred when the city was not discharging its wastewater, Mottl said. Also, city staff take water quality samples each time a fish kill is reported and have found that the ammonia concentrations were not toxic in the areas where the fish died, she said.
However, tests submitted to the health department shows that ammonia concentrations in the marsh have exceeded toxicity levels several times this year, and since March those instances have increased, Rockeman said.
While the marsh is primarily home to minnows, the backwaters of the Missouri River used to have large concentrations of northern pike and walleye, Ryckman said.
“Up until these last few years, that was a tremendously popular place to fish,” Ryckman said. “All that has basically been lost now because of the toxic and poor quality flows. The fishermen have been seriously impacted there as well.”
Miller said he would no longer fish in the Missouri River backwaters.
“I want to eat the fish I catch,” he said.
While the backchannel of the Missouri River is hurt by the wastewater, the effects decrease in the main river channels, Ryckman said.
“It’s still not a good thing to put in the river,” Ryckman said. “But it’s a small volume compared to the flow of the river.”
Out of options
Although Williston is not currently able to treat for ammonia, the city is meeting other health department standards, Rockeman said.
To be in compliance with its health department permit, Williston must meet certain milestones with the construction of a new plant. So far, the city is ahead of schedule, and the permit requires the plant to be complete by Nov. 1, 2016, Rockeman said.
Construction on the new facility began last fall, with crews working from 3:30 a.m. to 9 p.m. six or seven days a week to meet an expedited schedule, said Darrell Schneider Jr., construction services manager with AE2S, which designed the facility.
When it’s complete, the new facility will be able to accommodate a population of 60,000, with the ability to expand up to 100,000 if the population grows, Tuan said.
A portion of the plant is expected to be operational by this fall that could treat 2 million gallons of wastewater per day and remove the ammonia, Schneider said. The remaining 500,000 gallons of wastewater the system handles each day would go through the existing lagoon system until the plant is complete.
The Army Corps of Engineers owns and operates the marsh for flood control and pumps water over a levee five days a week into the Missouri River.
While Corps officials are also eager to see the plant begin to operate this fall, they warn that the situation could hit a critical stage soon as the elevation of the marsh drops to a point where they’re no longer able to pump, Gouger said.
The Corps can no longer pump from the marsh once it hits a target elevation, and the water was about 6 inches above that level last week, Gouger said.
“It’s better for the aquatic habitat if we keep pumping, but we cannot do it for their wastewater treatment plant purposes,” he said.
He worries that the scenario will cause more toxic levels of ammonia to build up in the marsh.
“And then when we do start pumping, you could pump that acutely toxic level of ammonia over the levee and create impacts to the aquatic habitat,” Gouger said.
Ryckman also anticipates that the issues will worsen this summer.
“The poor water quality will lend itself to more fish kills and more water quality problems this summer,” he said.
City officials say the concern about the Corps no longer being able to pump has been on their radar since April and they’ve discussed it with health officials.
“At this time, we just don’t have any other options,” Mottl said.
The health department’s stance is the city should focus all efforts and resources on completing the new plant, Rockeman said.
Williston officials, who coordinate weekly with the health department, the Corps and other interested agencies, are trying to do everything they can to protect the Missouri River, which is also the water source for Williston and surrounding communities, Tuan said.
“The water quality in general is one of the biggest priorities for us, not just on the wastewater end but on the water treatment end,” Tuan said. “Protection of the Missouri River ecosystem is No. 1 in terms of our priority.”
The other stakeholders acknowledge that the rapid population growth has put Williston and the health department in a tough spot.
“There’s just lot of things about this whole Oil Patch and oil development now,” Ryckman said. “Everything happened way too fast. There’s a lot of people that said it should have been slowed down and it wasn’t.”