Neil DeRiemer and his wife, Karen, used to look out their bedroom windows and see a waterfall cascading over a small dam just a few feet away.

Like their neighbors, they watched blue herons, white egrets, and black turtles wade in the seven-acre basin that made their East Goshen homes waterfront properties.

"It was like living in Longwood Gardens," said DeRiemer, 70. "How many waterfalls are left in Chester County?"

Now Hershey's Mill Dam is dry, its basin drained after it failed state safety inspections about nine years ago.

And township officials are facing a decision that has languished for years: what to do with a dam that some consider a defining landmark for their small Chester County community.

The stone and concrete dam, which tops a 450-foot-long earthen embankment along Ridley Creek, has been part of the town since at least 1748. It once powered the historic mill building where DeRiemer now lives. Drivers traveling up and down the local Greenhill Road off Route 202 have a clear view of it.

Over the recent decades, dozens of couples memorialized their wedding day with photographs in front of the waterfall.

"It was part of East Goshen," said E. Martin "Marty" Shane, a longtime township supervisor.

Hershey's Mill Dam isn't the only structure of its kind whose fate is uncertain. Supervisors are also mulling what to do with Milltown Dam, which is larger and would endanger a cul-de-sac of residents if it failed.

"The decision on what to do on either one of the dams will be one of the toughest decisions I've had to make in 30 years," Shane said.

They have faced the decision before. After the recession, township officials had the chance to use federal stimulus funds to remove Hershey's Mill Dam. But residents pleaded for a chance to save it, and supervisors gave it to them.

After a batch of repair and cost studies, residents were given one year - until the end of 2015 - to raise more than $400,000 needed for repairs.

They collected only $1,500.

DeRiemer was the leader of the effort, dubbed Friends of the Hershey's Mill Dam. But when his wife died last March, his grief dropped him into a depression that sapped his enthusiasm, he said.

Without a leader, other residents drifted away from the group.

Now, DeRiemer said, he is back in action and wants a chance to reenergize the campaign.

At a meeting last Tuesday, he asked for more time. But officials said their hands were tied: A federal permit for work on the dam is set to expire in June, so construction - to either repair or remove - must start by then, they said.

Hershey's Mill Dam is one of about 300 state-regulated dams in Pennsylvania that could wash out a roadway downstream if they failed. The dam is only 14 feet tall and does not hold back much water, but officials worry about Greenhill Road, fewer than 200 feet away.

A new federal permit now in the draft phase could push the deadline back to the end of 2019, said Roger Adams, chief of the Department of Environmental Protection's Division of Dam Safety. That would give residents more time to raise money.

"It's tough to get funding for dams right now," Adams said.

There is more attention spent and money reserved for dams responsible for protecting people against floods or holding water supplies. Recreational dams, such as Hershey's Mill Dam, do not have similar government programs, Adams said.

Proposed plans to rehabilitate the dam include building a new spillway to increase capacity over it and raising the crest of the dam.

DeRiemer knows people care about the dam.

One day last summer when DeRiemer's brother was at the house, he saw a widow and her children come to send their patriarch's ashes over the dam's waterfall. They were disappointed to find it dry.

DeRiemer hopes to tap into that support using social media and a crowdfunding website to capture more interest. He even has pins ready to give to benefactors.

They say: "I gave a dam."