When Andrew Mason arrived to take the reins at YMCA Camp Letts two years ago, plans were already afoot to check serious runoff from the camp's horse enclosure into the Rhode River.

Mason said he wasn't totally sold on the idea until the West/Rhode Riverkeeper helped him understand the benefits of the project for both the river and the camp's grounds.

Soon he was on board, and the partnership did not stop there. Now, the fifth major restoration project at the YMCA camp — building an 850-foot living shoreline at the tip of the camp's property on the peninsula between Bear Neck and Sellman creeks — is about to get underway.

"I became a staunch supporter," Mason said. "And what a collaborative effort it has been, with the Riverkeeper, county and state agencies — just wonderful to work with."

The Riverkeeper did a detailed survey of the West and Rhode river system in 2009. The camp's sloping horse corral and riding enclosures were spotted as a major source of sediment runoff into Sellman Creek, just above where that stream joins the Rhode River.

"Camp Letts had several areas requiring attention," said current West/Rhode Riverkeeper Jeff Holland.

The first day of the survey then-Riverkeeper Chris Trumbauer got a phone call from the crew in the field. They said, "We've got one for you," Trumbauer recalled.

A wetland and a series of step pools to trap sediment and slow runoff from the horse enclosure were finished in spring 2013, with the assistance of cooperation and grants from the Chesapeake Bay Trust and help from the county and state.

But while the step pools stopped the flow to the river, they would soon have been filled by the equestrian area's runoff, Mason said.

So the county Soil Conservation Service, the state departments of Agriculture and Natural Resources and the county school system's Arlington Echo outdoor education center were consulted.

"What we did was reforest most of the open, bare earth area," said the Riverkeeper's restoration manager, Joe Ports.

About 200 trees were planted by volunteers and South County Middle School students last fall.

A horse paddock area with special drainage was put uphill of the reforested area. "We built eight 1,300-square-foot paddocks, and established a rotation schedule for the horses," Mason said. "It took some brainstorming."

All this stemmed from the push by the West/Rhode Riverkeeper organization. "This is but one step on the way to improving water quality," Holland said.

Ports said the work not only reduced sediment but is having other positive results.

"There are two kinds of salamanders on the restored channel, and tree frogs too. Warblers have been spotted and, unexpectedly, marsh hibiscus seems to be taking hold."

Next up is preserving 850 feet of shoreline by constructing rock sills just offshore and planting grasses inland.

"We should get a balanced combination of high marsh and low marsh, and the sills will dissipate the wave energy that has been eroding the shoreline," Ports said.

The Chesapeake Bay Trust, which helped fund some of the work, honored the Riverkeeper/Camp Letts initiative with this year's Melanie Teems Award, one of five environmental awards presented throughout the bar watershed.

The award was given not just for the work but for the example of cooperative efforts using several restoration techniques.

"You have a property owner on one hand and the Riverkeeper with the expertise — together they benefited the waterway and the land itself," said Jana Davis, executive director of the bay trust.

The restoration projects also gave county school students firsthand experience with restoration, and will be a stop for YMCA campers on the property's nature trail, Davis and Mason said.

"We have all become better stewards of the camp and our rivers because of this," Mason said.

Next up for the Riverkeeper: Projects to reduce runoff from the county's Avalon Shores fire station in Shady Side and a much larger project to restore a runoff-ravaged section of Muddy Creek.