COLUMBIA — The Boone County Commission held the first reading of a proposed ordinance Thursday that would make vegetated zones between streams and development mandatory.
Bill Florea and Stan Shawver, both of Boone County Planning and Building, presented the ordinance, which establishes the stream buffers. The plan, which is similar to one adopted by Columbia in early 2007, has been in the works for more than 10 years, Shawver said.
Florea said the primary purpose of the policy is to protect the integrity of streams as well as mitigate the risk to property from flooding.
The proposal states that vegetation along a stream can filter pollution before it gets into the water system; that trees provide shade that wildlife indigenous only to streams need to survive; and that the roots of vegetation within the stream buffers prevent erosion. Maps from the National Oceanic and Atmospheric Association's Hydrologic Data System show there are at least 1,800 miles of streams in Missouri, not including Missouri River drainage.
All of unincorporated Boone County falls under the jurisdiction of the ordinance, which would strictly define what kind of development can and cannot be conducted within the stream buffer.
The regulation divides the buffer zone around a stream into two sections: a streamside zone, which is the half of the buffer closest to the stream, and an outer zone, which is the half farther away from it. The streamside zone is designed to protect the stream from physical and ecological disturbances, while the outer zone is designed to filter and slow water runoff.
Development in streamside zones is limited to flood control, permeable surfaced foot and bicycle paths, road crossings, utility crossings and nature restoration projects. Outer zones would allow hard-surfaced biking and hiking paths, water-control structures, major utility corridors, residential yards and landscaped area, according to the proposal.
The size of the buffer around any given stream depends on the type of stream in question. Perennial streams, identified by solid blue lines on United States Geological Survey maps, would require a 100-foot buffer. Intermittent streams, shown as a dashed blue line on survey maps, would require a 50-foot buffer. Intermittent streams and water canals not shown on survey maps would only need a 30-foot buffer, according to the proposal.
The proposal indicates that existing structures that fall within the stream buffers would be grandfathered in and thus not subject to the regulation. In the future, they would only be able to expand vertically or away from the stream. Individuals can petition the Boone County director of public works or the Board of Adjustment for a variance if an exception to the policy is thought to be needed.
Violations of the ordinance would be a misdemeanor crime, and violators could be subject to both civil and criminal prosecution. The commission hopes Public Works officials can be cross-trained to recognize violations while they are out performing other duties in order to reduce enforcement costs.
The regulation specifically exempts agricultural and mining activities from having to comply with the ordinance. Florea of Planning and Building explained that although these industries can be major sources of pollution in streams, Missouri state law officially exempts them from being regulated by local entities.
Bob Hagedorn, a district conservationist with the Natural Resources Conservation Service, thinks stream buffers are needed to separate them from agriculture zones.
“From an agricultural point of view, what we like to have is some buffering like a tree corridor along the stream with grass strips on the outside," Hagedorn said. "Timbered corridors can prevent sediment deposits from agriculture from filling in a stream, as well as absorb harmful nutrients and pesticides. There should be at least a 30-foot minimum in an agriculture situation.”
The stream buffer ordinance must now be scheduled for a second reading before the commission will vote on whether to adopt the policy.