 
Development has altered the natural flow of water through the watershed. Before the watershed was developed, most precipitation would soak into the soil or evaporate from plants and trees. The remaining runoff would slowly make its way through a network of streams, lakes and wetlands and eventually end up in the ocean. As more people moved to the watershed, houses, roads, stores and parking lots replaced natural vegetation with many surfaces that do not absorb water. These impervious surfaces prevent water from soaking into the soil and cause a larger amount of water to run off into nearby streams or be carried to those streams through the storm sewer system, which greatly impacts streamflow.  |
