With an increasing number of railway spills causing environmental and human health risks, underground pipelines are touted as a safer way of transporting oil, natural gas and chemicals.
Now, it appears, you could add manure to the list.
A new study suggests it might be possible in Manitoba to send 60 million gallons of liquid hog slurry a year through a buried pipeline up to 35 miles long.
The purpose would be to transport nutrients from municipalities with surplus manure to places that could use it, according to the study by the Winnipeg firm DGH Engineering for the Manitoba Livestock Manure Management Initiative.
The project, while technically feasible, would be enormously expensive, costing close to $43 million. It would also face significant hurdles, such as securing rights of way and alleviating public opposition to manure flowing underground past people’s homes.
But the fact it is being considered at all suggests alternatives to transporting manure in Manitoba may eventually have to be considered, said Mike Teillet, sustainable development manager for the Manitoba Pork Council, which helped fund the study.
“We didn’t really think it was going to be viable, but we thought we needed to look at it,” Teillet said.
The project is in response to surplus soil phosphorus in southeastern Manitoba’s livestock alley, where many of the province’s hog farms are located. In particular, hog manure in the municipalities of La Broquerie and Hanover sometimes exceeds local soil nutrient capacity, creating the need to transfer manure farther west where it can be safely used.
“We knew it was technically feasible. We wanted to get a costing on it,” said Teillet.
The study develops a concept design for a 14-inch-diameter high-density polyethylene pipeline buried along public road allowances. The design includes a two-million-gallon surge tank and a pumping station at the starting point with two booster pumps along the way. Three storages, each with a two-million-gallon capacity, are at the end.
The capital budget calls for a $42-million mortgage with annual payments calculated for both 10- and 25-year paybacks. The cost to pump manure through the pipeline would be 11 cents and seven cents a gallon for 10 and 25 years respectively, dropping to two cents a gallon after the mortgage expires. It would cost another 1.5 to four cents a gallon to pump manure from hog farms into the pipeline and from the pipeline to receiving fields at the other end.
The project, which would operate only during the application season, would require a general manager, a maintenance technician and a support worker.
Despite the cost, transporting manure through an underground pipeline could work, the report concludes.
“The use of a pipeline to transport manure a distance of 35 miles appears to be technically feasible, notwithstanding a manure pipeline of this scale appears to be unprecedented,” says the report.
But it adds that public concerns about potential spills could make it hard for the project to receive an environmental licence.
“An extensive environmental assessment will be required and it is recommended that a comprehensive public consultation program be implemented to address public concerns and gain public acceptance.”
The report also says the support of municipal governments on whose property the pipeline might cross “would be paramount.”
Teillet said because the idea of a manure pipeline is foreign to people, they might object to it despite the fact that sewer lines are common.
“Even though we have sewer lines all over the place, people would probably object if they had one of these things running down in front of their house.”
A current provincial moratorium on new hog operations, plus tougher regulations on manure handling, could render the idea moot anyway, said Teillet.
But if the industry ever starts to expand again, it may have to look at other ways of transporting manure besides trucking it, which is hard on roads and carries the risk of accidental spills, he said.
“When you run a bunch of trucks, things happen. As careful as people can be, things happen.”
Because the project would be so expensive, Teillet suggested it could be funded through a local co-operative or a consortium of producers in the area. Some government funding might also be available.
The idea of transporting manure by pipeline is new in Canada but not unheard of elsewhere. DGH engineer Charles Liu, who prepared the study, said he has spoken to a company in Wisconsin trying to develop a commercial project. Some hog operations in Europe pump liquid manure from a lift station through a pipeline to a digester.