What is so Critical about the Critical Area?

The term critical area is a familiar one for most Severna Park and Broadneck area residents who live near the water. By definition the Critical Area is a 1,000-foot-wide zone of land that runs inland from the mean high tide line along the shoreline of tidal creeks, rivers, or the Chesapeake Bay and from the edges of tidal wetlands. This zone also is meant to have a 100-foot-wide vegetated buffer zone along its shorelines.

According to the Anne Arundel County Office of Planning and Zoning, www.aacounty.org/PlanZone/Development/CriticalAreas.cfm, the Critical Area Law was passed by the General Assembly in 1984 to help reverse the declining health of the Chesapeake Bay and its tributaries. In 1988 the county began implementation of the Critical Area Law after its plan had been approved by the State Critical Area Commission.

There are three land use classifications stipulated in the Critical Area Law: Intensely Developed Areas (IDAs), Limited Development Areas (LDAs), and Resource Conservation Areas (RCAs). Each of these classifications defines and determines the type of development and storm water management in a given area of land.

IDAs are areas of land where 20 or more acres of land where residential, commercial, institutional, or industrial uses predominate. In these areas storm water runoff must be reduced to levels 10 percent below the levels of the site prior to development.

RCAs compose 80 percent of the land in the state. They are made up of open spaces such as agricultural land, wetlands or forests with less than one dwelling per five acres.

Most of us live in LDAs which are land areas with four dwelling units or less per acre and have public water or sewer or both services. Looking at the map accompanying this article, the shaded areas will show how densely populated the critical areas are in the vicinity of Cattail Creek in Severna Park. Population densities are similar along other shorelines in Severna Park and the surrounding area.

Since so many of us live in the Critical Area it is important that we understand how to best maintain our yards in order to reduce or eliminate storm water runoff pollution from entering our local waterways.

The motto of RainScaping.org (www.rainscaping.org/) provides us with an easy way to remember how to effectively deal with storm water: “Slow it down; spread it out; soak it in.” When we capture storm water and allow it to soak into our yards we help protect the waterways in our local critical area from the harmful effects of pollution.

Capturing pollutant laden storm water in critical area yards can be accomplished by installing rain barrels, rain gardens, or grassy swales and maintaining the required 100-foot vegetated buffer zone along the shoreline. It's important to note that lawns that extend right to the water’s edge are not considered the best example of a vegetated buffer. It would be better to leave existing trees and shrubs as the buffer zone or landscape with native plants if the area has been cleared.

For additional information about the Critical Area please visit the website for the Maryland DNR at:

 www.dnr.state.md.us/criticalarea/index.asp .