Alan Lishness Hobsons Wharf.jpg


Dredging the Slips

There's a lot of silt between Portland Harbor's wharves and piers, and some of it is very, very dirty. For decades, pier owners have worked to incite a collective effort in the Portland community to remove and dispose of this material. With many stakeholders dedicated to waterfront access and increased berthing, the question still remains: Once we remove it, where do we put it?


To hear the story, watch the slideshow above. If you prefer audio only, go here.


Take a walk along any of Portland Harbor's wharves at low tide and you're likely to see a whole lot of mud. Some of this build up is natural - silt drifts from the Fore River and settles along docks and piers. But mixed with all that "clean" mud, there's a lot of material that is very polluted.

Portland's industrial past plagues this silt. Chemicals like lead, mercury, and cadmium have been found in the mud - legacy pollutants from the city's paint factories, metal foundries, and filling stations. And, even now, chemicals such as polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) wash into the slips from combined sewer overflows. Stormwater runoff from busy city streets is full of nasty chemicals that settle in the silt between wharves and piers. 

For pier owners, dredging is maintenance. It's like paving a parking lot or painting a house. Charlie Poole, President of the Proprietor's of Union Wharf, has lead efforts to get dredging underway. For him, deepening the berths and maintaining waterfront access on Union Wharf is essential for a working waterfront to survive. 

"I like to think that we're an artery from the mainland roadways to the sea and from the sea back to the roadways so we're a place for people to conduct business. One of the key elements of owning a pier is to allow people whatever the size vessel the appropriate depth of water so they can come and go and do their business." 

The decades (maybe even centuries) of pollutants and chemicals in Portland Harbor's silt make dredging between wharves and piers a difficult and controversial issue. Many environmental groups agree the material should be removed, as part of the continuing effort to clean up Casco Bay. But the issue of where to put it is still in question...

To hear from the various stakeholders, both supporters and skeptics, of the dredge project watch the audio slideshow above or listen to the audio story here.

Galen Koch © 2016

Galen Koch © 2016

Custom House Wharf at low tide. Galen Koch © 2016

Custom House Wharf at low tide.
Galen Koch © 2016

Boats tie up on Union Wharf and Merrill's Wharf. Galen Koch © 2016

Boats tie up on Union Wharf and Merrill's Wharf.
Galen Koch © 2016

Wharfside: Stories of Portland Harbor's Working Waterfront explore the people, places, and work in Portland Harbor through photos, audio stories, and video. This project is made possible by the Waterfront Alliance and Casco Bay Estuary Partnership. Photos for this story by Galen Koch and Jenny Rebecca Nelson © 2016. Music for this piece provided by Ross Gallagher, Andy Cohen, and Chris Zabriskie. Animation assistance from Lake Buckley.

Produced by Galen Koch © 2016.