"It's one of these 'Catch-22' scenarios," he said.
The state's attitude changed this year, residents say, after they enlisted the help of their state senator, E.J. Pipkin, a Republican who recently resigned his seat to move to Texas. After last summer's water scare, he pressed state officials to take a more active role in trying to fix the creek, writing a series of letters and holding a meeting in May.
"The waters of Northwest Creek are owned by the State, and the State should have the primary role in the creek's maintenance," he wrote the state environmental secretary in February.
Since then, the state has allocated $40,000 to draw up a plan for restoring the creek and awarded the contract recently to a Cambridge firm.
Smith acknowledged the former legislator's advocacy, but said officials were moved by the circumstances, not political pressure.
"When you have habitat and human health issues come into play, that changes the whole tenor of the thing and cranks it up a couple notches," Smith said. "We all recognize there's an issue out there [and] we need to address it. ... It's not going to go away."
The plan should clarify options for restoring the creek and clear the way for regulators to issue permits, but that still leaves the question of who will pay for the remedies.
"That is a bridge we haven't gotten to yet," Smith said. "We're talking about a project that's going to be pricey, and it's not determined where are those funds and who's going to pay for it."
Part of the algae problem might be self-inflicted, the DNR official said. Scientists studying the creek measured high ammonia levels there at one point, indicative of a glut of nitrogen. All the homes are on septic systems, and nitrogen from them might be seeping into the water. Some farmland still drains into the creek, raising the possibility that fertilizer might be running off, Smith added.
Wilson said residents know they must share in the effort to return the creek to vitality.
"There's snapping turtles and a few snakes in there," he said, "but really nothing else at this point. It really is a shame."
Meanwhile, scientists with the University of Maryland Center for Environmental Science have been testing remedies for knocking out the bloom.
Just off Walker's dock, they have experimented with a treatment that includes spraying the water with a compound made from ground-up crab shells. The acidified solution gets the algae to clump, and after a layer of fine sediment is sprayed on the surface, everything sinks to the bottom, leaving the water clearer.
"We're trying to do this with the cheapest method possible," said Allen Place, a professor at UM's Institute of Marine and Environmental Technology in Baltimore.
Place and colleagues rid the Girl Scout lake of its problem, but only after draining it — something that would be costly and complicated for Northwest Creek, given its size and proximity to the bay.
Walker welcomed the scientists' efforts but said residents believe dredging offers the best option.
"That's an interesting solution, but it's not a long-term solution," he said. "What we want to do is a forever solution."