About the Watershed
A watershed is common ground and a healthy one is a common good.
We all need water everyday. “The world has no more fresh water than it did 2000 years ago, when the population was less than 3% of its present size.” - Earth Island Journal, “Water Wars, Water Cures”, Spring 2000.
A watershed is a land area that drains rain water above and below the surface to a single resource. The force of gravity carries water to its destination while the landscape topography determiners the path. Overtime, the landscape is carved with streams. Aquifers are underground water storage — layers of water-bearing rock. Many groundwater springs supply baseflow to Richland Creek and its branches, everyday.
The hydrologic cycle replenishes our water resources — is a system of land, air and water interactions. Temperature and wind speed affect the rate of evaporation from surface storage (streams, rivers, wetlands and lakes). Underground flow can surface as springs or seeps and provide flow to streams throughout the year.
Richland Creek is an urban watershed with 5 major tributaries: Sugartree, Unnamed Tributary, Jocelyn Hollow, Vaughn's Gap, Belle Meade and many smaller spring branches that feed the system (USGS Map of Creeks).
Where does our pollution come from? Urban watersheds have significant land area covered with impervious landscape (rooftops, roads, parking lots, structures). These nonabsorbent surfaces collect all types of pollutants that then flow to streams as run-off. Adding to the mix is overuse of lawn and turf treatments, construction sites that lack adequate soil erosion protection, illegal discharges and trash dumped or not disposed of properly. The stormwater system collects it all, which flows into streams unfiltered and untreated during each wet weather event. More storm runoff over undeveloped land, into rain gardens and across riparian buffers would allow natural diffusion through soil layers and filtration of pollutants by plants and trees. Significan pollutants — oil, grease, dirt, chemicals or other harmful substances dripped, left or spilled onto surfaces degrade water quality and harms aquatic ecology.
Groundwater flows beneath the surface, through unseen pathway. Dissolution of the soluble bedrock (limestone) layers overtime create karst landscape — geologic formations of caves, tunnels and sinkholes. Surface pollution can enter and contaminate groundwater resources more easily in karst topography. Aquifers provide groundwater storage and keep our streams flowing healthfully year-round.
Water supply is limited. Of the enormous amount of water on the planet only 1% is suitable for consumption — 97% is sea water and 2% is ice. Of that 1%, only 10% is accessible— 60% of water resources are where only 40% of the global population resides. Water demand is growing at an unsustainable rate while much of our supply is returned polluted.
Our sustenance, health and economy are dependent on clean water for drinking, agriculture, fisheries, energy production, manufacturing, recreation.. and many other uses that support our way of life. Streams are important no matter where they are located and keep the system flowing. Surface runoff replenishes the water cycle and needs regarded as a valuable water resource, even in an urban watershed.
The Clean Water Act tells us our waters are impaired. Richland Creek watershed streams are federally listed as "impaired" due to sewage collection failure, urban run-off and habitat alteration — 20+ stream miles are not meeting the regulatory, designated requirements — aquatic habitat and recreational uses.
The Federal Water Pollution Control Act Amendment of 1972 was enacted due to excessive industrial discharge into water resources. The U.S. Environmental Protection Agency was created to protect human health and the environment by writing and enforcing environmental regulations based upon laws passed by Congress. This legislation addressed point-source pollution.
Urban run-off (non-point source pollution) degrades streams' water quality and is of major concern now.
The Division of Water Pollution Control at the Tennessee Department of Environment and Conservation (TDEC) has compliance responsibility for protection of Tennessee waters. TDEC issues permits to cities and industries that want to use our resources or discharge into waterways. The Tennessee Wildlife Resources Agency comments to TDEC for protection of Tennessee's wildlife.
Nashville is currently under a Consent Decree mandating infrastructure improvement to address sewage discharges and overflows into the river and streams. The old sewage collection system in Nashville is in need of repair and updating, with some sections 100 years old. Capital improvement of system will eliminate these pathogens from flowing into our waterways and significantly improve water quality.
We all contribute to pollution... and can take actions to improve the water quality of our streams
|Non Point Source||Point Source|
|discharges with weather||discharge from pipes|
|difficult to identify & control||easy to identify & control|
|stormwater run-off||constantly discharges|
|structures, roofs, pavement||wastewater treatment|
|construction and agriculture||energy production|
|lawns and turf||industry|