Ocean View receives stormwater tutorial

The Ocean View Planning and Zoning (P&Z) Commission returned to design templates for the Route 26 corridor at a Nov. 17 workshop, spending most of the meeting in question-and-answer with Sussex Conservation District’s Jessica Watson.

The conservation district, first and foremost, manages and maintains the network of tax ditches around the county. Supported by localized tax ditch associations, these networks facilitate drainage toward the nearest body of tidal water.

But the conservation district does a lot more than tax ditches — staff also reviews stormwater management plans for all developments that disturb more than 5,000 square feet of ground.

Lately, that’s a lot of developments. Watson said she’d started in 2002, and the conservation district saw 142 new projects that year. And then another 173 projects in 2003. And another 190 projects in 2004.

“It looks like we’re going to exceed that number this year,” she noted — and said she expected that trend will continue for some time yet. (Important to keep in mind: those numbers didn’t reflect the size of the projects, Watson added. Any given one could be as simple as a small commercial business or as complex as an 800-acre golf-course community.)

The conservation district is seeing a new breed of project these days, Watson continued — for instance, the big 1,700-home Bayside golf community, under construction on Route 54.

“According to state law, you can’t disturb more than 20 acres at a time,” she noted. “So, how do you build a golf course, with various ponds that might be an acre or more in size?”

Despite the difficulties, Watson suggested Bayside had managed to keep impacts to a minimum, and the conservation district considers the project a success story.

Getting back to Ocean View, Kyle Gulbronson (URS), on retainer as professional planner for the town, asked Watson whether the conservation district ever considered cumulative runoff from multiple developments. “Here, it’s more in-fill projects,” he pointed out.

Watson said they had not considered projects cumulatively (unless they were side-by-side, and under construction at the same time), but they were starting to move in that direction.

For the first time, the conservation district is planning to look at Fairway Village (332 residential units) alongside Wedgefield/Avon Park (179 residential units), both along Ocean View’s south side — especially the impact these developments would have on tax ditch capacity.

“We’re checking culverts capacity, where they’re blocked,” Watson said. “We know we have drainage problems, so we’re looking at these projects very carefully.”

She warned P&Z commissioners they would probably have to deal with the “wet pond” variety of stormwater management, because of an extremely high water table.

Watson pegged the wet ponds as by far the best option for a place like Ocean View.

“Bioretention,” and “infiltration basins” (drains installed in natural, shallow depressions) are a challenge, she said, because they probably won’t dry out. They’ll turn into shallow, stagnant pools — a breeding ground for mosquitoes.

“Bioswales” (shallow, grassy ditches) could work with a nearby outfall (tax ditch, creek, etc.), but again, with such a high water table, there is a good chance tidal waters would back up into the swales, she said. Again, they’d never dry out. Again, mosquitoes.

Watson said the state administration did prefer these “green technologies,” but recognized they just wouldn’t work in certain areas.

In wet ponds, she said, fountains are a good feature — they stir the water enough to prevent the maturation of mosquito larvae along the banks. And while the state recommends a 3-foot minimum, 6-foot maximum depth, Watson suggested the deeper the better.

This left commission members with the fear they’d identified in earlier design workshops — that every single parcel along Route 26 would end up with a wet pond in the front yard.

However, Watson said the town could impose design criteria that would at least require developers to move some of the ponds into the back yards of lots.

Even if the lot’s natural flow tended toward the street, the town could do this, she said. The flow could be reversed simply by running pipes back toward the wet pond. That would undeniably be more costly for developers, but Watson said the Sussex Conservation District would support the town if it chose to adopt that design criterion.

Kyle Gulbronson (URS), on retainer as professional planner for the town, asked why the conservation district didn’t require fences around stormwater ponds.

Watson said the state had run a study and found children could scale a fence a lot quicker than an adult could climb after them. Instead, the conservation district required “benches” inside wet ponds — anyone who fell in would land on such a shallow, underwater shelf and could simply stand up and walk back out of the pond.

Ocean View’s Charles McMullen (administrative official, public works supervisor) asked Watson if there were any guidelines regarding a minimum distance between ponds and houses. She said “pond-front” real estate was a selling point, even if the ponds were artificial.

However, building right on top of them sometimes led to problems with maintenance. And Watson admitted there’d been some back and forth, with the conservation district expecting town and county P&Zs to handle those setbacks, and town and county P&Zs expecting the conservation district to set the standards.

“Now, we’re asking for 20 feet,” she said — but that is just a recommendation, unless the town decides to codify some restrictions themselves. McMullen said there were some projects around town where the ponds were basically right outside the back door, and Gulbronson noted a project in one of the other towns he consulted for where the developers built decks “almost over the pond.”

P&Z Chair Dick Logue returned to one of his pet peeves — the fact that builders are sometimes directed to cut down trees in order to build stormwater management. Watson agreed — it didn’t make much sense to her, either. But if the developers were willing to get creative, there were ways to add some vegetation and create a “filter strip” stormwater feature, utilizing the existing natural resources, she said.

On that note, the P&Z turned an early draft of a tree preservation ordinance, in development at the City of Rehoboth Beach. (Per Rehoboth’s comprehensive plan, at least 40 percent of every buildable lot in the residential districts must remain as a natural area.)

Ocean View’s P&Z and town staff planned to meet again next month (Dec. 15), and between the draft tree ordinance and Watson’s presentation, they should have plenty to think about until then.