Chapter 16 – Almost everywhere, except in Charles County, 10% impervious surface is accepted as the tipping point that results in serious, probably irreversible, damage to a waterway.
It’s important to understand that impervious surfaces are the pavement and rooftops associated with development that prevent rainwater from soaking into the ground. More impervious surfaces result in a more polluted waterway.
County Government Staff Are Playing a Shell Game with Impervious Calculations
After four years of calculating the impervious surface for the Mattawoman Creek watershed and always coming up with projections that are greater than 10%, the county government and their consultant are now trying to over-power science with idle conjecture.
The county government would like to downgrade the impervious surface numbers for all future development projects using ESD (Environmental Site Design). No one knows how effective ESD would be if it were used in a perfect world. It doesn’t matter because, by law, the applicant only has to use it to the Maximum Extent Practicable. The Charles County Storm Water Ordinance, riddled with administrative autonomy, provides six pages of options for exemptions, variances and waivers of ESD.
So, instead of changing the comprehensive plan to reduce the amount of development, which would reduce the impervious surface numbers, the consultant hired by Charles County is reviewing the impervious surface calculations to determine if impervious surface rates are actually lower than 10%. In keeping with the long-standing county government policy to exclude the public, the new impervious surface numbers won’t be available until after the October 5th public hearing of the Planning Commission. That’s the government at work, Charles County-style.
Read more from our ongoing series, “Charles County’s Comprehensive Plan fiasco.”