Many of Montgomery County's older urban and suburban areas were developed in an era when paved surfaces (roads, parking lots, driveways) were built up without concern for what would happen to rainfall runoff. Stormwater management was not as big a concern as it is today. These areas did not develop with adequately sized stormwater drainage systems and stormwater ponds to receive, detain, and filter runoff before it flowed into streams. As a result, during rain events runoff flushed into streams unmitigated. Damage to the local creeks and streams that flow through these neighborhoods was the unfortunate result.
Storm drains deliver rainfall runoff directly into streams, which in older areas without good ponds and volume management has destroyed stream structure and biological life.
Streams are fragile systems, and often they are unable to withstand the cumulative impacts of urbanization. Types of stream damage include:
Structural damage to streams. Channel and banks are destroyed, affecting the habitat available for biological life in the streams.
In-stream pollution. Stormwater picks up and carries trash and debris, as well as chemical pollutants such as petrochemicals from vehicles, and nutrients from lawn care.
Improperly functioning aquatic ecosystems. Fish, amphibians, and insects are often unable to survive or reproduce in polluted conditions.
Lack of forested stream buffers. Areas along streams lack good vegetation to retard pollution and erosion.
How Stormwater Destroys Local Streams
Examples of Stream Damage
The following are examples of stormwater-related stream problems encountered in many of the County's historically urbanized areas.
Exposed tree roots and eroded stream banks.
Eroded channel bottom, which exposes the sewer pipes crossing underneath.
Presence of trash, oil, yard waste, and other illicit discharges brought in by stormwater pipes.