Association of Vermont Conservation Commissions

Prior to 2009, the town of Jericho had a zoning district that covered land within 100 feet of major floodplains and rivers. The town was in the process of updating its zoning bylaws and came to realize that it needed to do something more to protect smaller streams. Sedimentation was occurring not only in the larger streams, but the smaller streams as well, which suggested that in order to protect the larger Lake Champlain watershed, streams of all sizes needed to be placed under protection. The zoning district was using older maps, so in some cases stream locations had shifted over time. This problem was solved by the implementation of a district overlay so that as the stream boundaries move over time, the district moves along with it. It was decided that a tiered approach would work best for this zoning district. Streams were classified in three orders based on size: major, medium, and small or unmapped streams. It was also decided that the buffer would start at the tops of banks (on both sides of the stream) because if a stream center line approach was used, wider streams would be disadvantaged by a narrower buffer. From the tops of banks major streams have a buffer on 100 feet, medium streams have a buffer of 50 feet, and small or unmapped streams have 35 feet.

This overlay district serves to minimize new development and regulate land use in these floodplains, in doing so protecting natural resources integral for healthy wildlife populations. New dwellings are not permitted in the overlay district and future development is very limited. Excavation, landfill, and grading are not permitted within the buffer area. Regulations require that the buffer must be made of undisturbed vegetation, rather than vegetative grass-clippings, with exceptions for agricultural fields, recreational trails, and low impact stormwater treatment practices. Another exception within this bylaw regards the regulations around preexisting historically significant structures built on buffers. An open-waiver process was created for this scenario which requires the applicant to submit an impact assessment regarding effects on wildlife, habitat function, and water quality. An additional bylaw was created which states that areas with over 15% slope need stringent water quality and erosion control standards. Any areas with over 20% slopes need to show impacts on watershed that occur past the buffer.

Jericho was one of the first communities at the time to adopt stormwater standards and treatment which exceeded those suggested by the state of Vermont. Jericho's standards now apply to parcels with only ' an acre of impervious surface whilst the state standard is one acre. This was an especially effective decision because most of the applicable development projects were under the one acre threshold, so they were not required to involve stormwater treatment in their planning. One potential treatment plan option for these developments is the addition of small catch basins at these sites.