Virginia is proposing new, stricter rules governing stormwater runoff, which occurs when fertilizer, oil, animal waste and other contaminants flow into public waterways.

Runoff from development sites, including lots and construction zones, is the fastest-growing source of pollution in the Chesapeake Bay, according to the Environmental Protection Agency.

The proposed regulations would dictate how new homes, businesses and roads are built, where new development occurs and how redevelopment happens in cities and towns. Each locality would have to manage a runoff permitting program or allow the state to do so.

Five public hearings on the proposed measures have been scheduled statewide. New regulations would take effect in July 2010 at the earliest.