Do Local Wetland Bylaws Slow the Conversion of Open Space to Residential Uses?
The conversion of open space land to residential, commercial, and industrial uses as cities develop is an issue of significant environmental concern. Local governments play a key role in land use decisions and can use a variety of policy tools to influence the rate of land use change or to permanently protect open space. An important but controversial form of local regulation in Massachusetts is local wetlands protection bylaws, which give towns and cities additional regulatory power over land near wetlands. This paper uses newly compiled information about land use regulations in towns and cities in eastern Massachusetts, in combination with data on land use changes and other community characteristics, to analyze the relationship between local wetlands bylaws and rates of conversion from open space to residential land uses between 1985 and 1999. We use variation in the timing of adoption of wetlands bylaws to examine possible effects on conversion rates, housing permits issued, and the ratio of land converted to residential use per new housing unit. We find that for communities with more than five percent of land area in wetlands, having a wetlands bylaw for the full extent of the 1985 to 1999 period is associated with an estimated 1.1–1.4 percentage point decrease in the rate of conversion of forest and agricultural lands to residential uses, after controlling for other factors. We find some evidence that wetlands bylaws may slow the rate of permitted single- and two-family housing units in cities and towns with more than five percent of land area in wetlands, but do not find that bylaws are associated with lower numbers of permits for all housing types. Finally, we find weak evidence that wetlands bylaws are associated with less land used per new unit of housing. Future research should further explore the question of how local regulation affects the spatial patterns of new housing and preserved open space.