The Merrimack River has been called "one of New England's treasures."
Stretching 125 miles, it supplies drinking water for six Massachusetts cities, including Lawrence and Methuen.
But below the surface, boatyards give way to graveyards.
Rocky Morrison is the founder of the nonprofit Clean River Project. He says they've pulled 64 cars from the river in a state that was once the car theft capital of the world. His group has also pulled up safes, refrigerators and about 8,000 tires.
The photos in the gallery above are just some of what necn saw.
Walking along the river, it's just as bad - tires, syringes, even shopping carts.
"You can see down here the magnitude of the debris that ends up in the waterways," Morrison said. "Bear in mind this is the drinking water for the communities up and down the river."
But the Clean River Project may be done cleaning up the river.
The volunteer group depends on donations and grant money. Funding from the Massachusetts Environmental Trust will allow them to pull 20 more cars from the river. But without help, that could be the group's final cleanup.
"Twelve years later, I find myself at square one," Morrison said. "I've got broken equipment, no sponsors, the cities and towns aren't helping out. Financially, it's a nightmare."
Haverhill City Councilor Tom Sullivan says it's time for a call to action.
"It can no longer just be done on a volunteer basis," he said. "Rocky and his group need state and federal money to finish the cleanup of this river, which is key to the redevelopment of the city of Haverhill."
necn Investigates requested water quality test results, but the Merrimack Watershed Association said it stopped testing five years ago due to lack of funding.