Saturday, May 25, 2013
The Portland Water District is worried about what may be a new winter tradition in Portland -- shrimp parts clogging the city's sewer system.
''They're starting to see pieces again at the treatment plant,'' said Michelle Clements, spokeswoman for the district, which operates the wastewater treatment plant at Portland's east end.
Last week, Clements said, workers removed shrimp shells, heads and antennas from screens that block trash and non-sewage waste from flowing into the plant.
The discovery quickly raised concerns about a repeat of last winter, when shrimp parts repeatedly clogged a downtown sewer pump station, disrupting operations and requiring water district crews to work overtime.
''So far, it hasn't been that excessive. We haven't had any clogs at the pump stations,'' Clements said.
But, she said, Portland city officials who regulate industrial discharges are planning to visit or contact seafood businesses along the waterfront in an effort to keep the shrimp problem from expanding.
''We're trying to avoid the problems we had last year,'' she said.
Shrimp season began Dec. 1, although catches have been limited so far because of bad weather and the fact that the shrimp have not yet moved closer to shore to lay eggs. Catches are expected to pick up in January, and officials are worried the sewer problems will, too.
Because of the volume of shells and antennas in the sewers this year and last, officials believe the wastes are coming from one or more waterfront businesses that process shrimp.
The companies -- both wholesalers and retail fish markets -- typically remove the heads and antennas, and sometimes the shells, before they are sold to consumers.
Larger processors have elaborate pretreatment systems that keep shells and other wastes out of the sewers.
Smaller operators, including some that operate sporadically, are required to at least have well-maintained screens to keep the solids out.
Last year, city inspectors worked with waterfront companies to repair or improve screens and stop sending the wastes into the sewers, said Steve Harris, who oversees industrial pretreatment compliance for the city.
But he's not entirely surprised the shrimp parts have resurfaced.
''It's a huge volume,'' Harris said. ''We may not have identified everybody that was doing it.''
The city will now contact the businesses again and conduct another round of inspections, he said.
''Any interference at the treatment plant obviously costs the city of Portland and its ratepayers money and we certainly don't want to the ratepayers subsidizing that,'' he said.
Staff Writer John Richardson can be contacted at 791-6324 or at: