City taking comment on flood hazard overlay idea, intercept ditch in Pepin Creek area
LYNDEN — The idea of a Flood Hazard Overlay on property in the Pepin Creek area was floated at an open house event for inquiring residents on Thursday.
The zoning proposal would have to be presented to the Lynden City Council for passage before becoming effective.
The point is to recognize the flood risk that exists on that northwest side of town — flat land with a shallow water table — as the city continues to plan for a whole new residential neighborhood there, said Mayor Scott Korthuis at the meeting.
It is only fair that new growth primarily bears the burdens of that development, including the challenge of water drainage, he said.
A map shows the overlay applying to all land in the city within the drainage of Benson and Double Ditch roads, where a new central Pepin Creek channel is envisioned. A moratorium on subdividing or building is in place now.
Still this year, the city would like to extend north an intercept ditch that already is visible in the 1600 block of Main Street. The new digging would be at least to the protective fly zone for the Lynden Airport, about halfway to Badger Road, city officials said.
This two-hour discussion opportunity was set up to present and get reaction to the city’s Emergency Response Plan. Federal money was received after a major 2009 flood in the area, and the action now continues to be part of the response.
The emergency plan is to have the longer intercept ditch catch flood flow and direct it south toward Main Street, whose surface itself could then act as a channel carrying water east to the bridge over Fishtrap Creek at Eighth Street, said those who presented Thursday, including city Planning Director Heidi Gudde and Public Works Director Steve Banham.
Plastic sheeting and sandbags would be used to seal and direct floodwater flow east on Main, according to drawings mounted for viewing.
“Our intent would be to keep [water] in the streets and not in [houses’] crawl spaces,” Banham said.
An overlay does not change underlying zoning. “The overlay is intended to let property owners, lenders and developers know that additional steps may be needed to adequately protect these properties from flooding. This includes voluntary flood insurance and constructing buildings to specific finished floor elevations,” the city states.
Eventually an overlay could be removed if flood control strategies are in place and shown to be working.
By far the worst flood to hit the area, by city records, was when peak flow of Fishtrap Creek at Front Street got to 1,200 cubic feet per second in January 2009. That is considered to have been an usual event, the convergence of many factors including sudden melt of heavy snowfall, clogged ditches and and an icy surface on fields keeping water from absorbing.
Public Works Director Steve Banham said the city will post electronic copies of the concepts of the intercept ditch and Main Street as water conveyance route to its website and will take comments from the public through Friday, July 5.