Camden’s new wastewater plant will send less sludge to the dump

Camden has just finished a big, $14 million project to upgrade its wastewater treatment plant that will address several environmental issues facing the region, including the need to safely dispose of sewage sludge that comes out at the end of the process.

Among the highlights of the upgraded system are technology that will dry out that sludge, reducing the volume of solid material contaminated with so-called forever chemicals that must be sent to the landfill.

The work also included the relocation of a sewer main line that had previously run under Camden Harbor to instead flow under local streets, and other changes that reduce the likelihood of wastewater overflowing during heavy storms and polluting local waterways.

Maine communities have been sending growing amounts of sludge to state landfills in recent years, since it became clear that the material can be contaminated with the harmful PFAS chemicals released by various products, and a law was passed in 2022 that banned spreading it on fields as fertilizer.

Now, more towns are starting to upgrade their wastewater systems with dewatering technology to reduce the amounts of sludge they must landfill.

Camden paid for its upgrades with a $1.4 million grant and a $12.5 million loan from the U.S. Department of Agriculture. It started the project in 2021 and just celebrated its completion at an event this week. The primary upgrades were made at the main wastewater treatment facility on Lions Lane and to pumping stations on Washington Street and Cove Roads.

The town will now be able to spend less on hauling its sludge to the dump, according to Town Manager Audra Caler-Bell.

“The new dewatering system that was installed as part of this project has really significantly reduced the volume of sludge the plant produces,” Caler-Bell said.

Other advantages of the upgraded wastewater system are that it will help the town to better manage the runoff from increasingly severe storms linked to climate change, and it will reduce how much energy is required to safely treat its wastewater.

Before the upgrade, Caler-Bell noted it was easy for rain and groundwater to enter the wastewater system. Combined with the wastewater already flowing out of toilets and sinks, that infiltration of freshwater added to the overall stress on the aging system.

“When you have cracked, leaky, old pipes that are failing even more, and you have more and more rainwater or groundwater that’s entering their system, it means that you’re treating a lot of water that doesn’t need to be treated. It’s a very energy intensive process to treat that water,” Caler-Bell said.

Caler-Bell noted that some other towns, such as Searsport, are in the process of making similar upgrades. Sewer districts in Lubec, Freeport and Southwest Harbor have also received USDA funding to help upgrade their own systems.

“This is a big issue, and it’s such an expensive investment for communities,” Caler-Bell said. It’s going to be one of the most expensive adaptations and resiliency investments to climate change that we’re going to make as an individual community, and then as a state.”