RALEIGH – A new state report concludes that Chatham County’s Rocky River watershed is safe for the public, but that managing the sources of waste in the watershed will be crucial to protecting the water from pollution.
The Rocky River Groundwater Assessment is the first in a new series of documents published by the state Division of Water Quality. More groundwater quality assessment reports are being developed for other watersheds in North Carolina. These reports will help provide a snapshot of groundwater issues and provide a valuable baseline for future comparisons.
This first report finds that groundwater quality in the Rocky River watershed is generally good and suitable for drinking water. However, it is anticipated that future development will add pressure to dispose of waste from nearby urban areas and increase animal waste from agricultural production. As such, proper waste management practices will be critical to the protection of groundwater and surface water quality.
About half of North Carolina’s population relies on groundwater for drinking water. Of the Rocky River watershed’s 32 community water supply wells, only one was found to have standards violations between 2005 and 2011, according to data obtained from the state’s public water supply section. That well was closed after an exceedance of volatile organic compounds was discovered. Community water systems are public water systems with 15 or more service connections or at least 25 year-round residents.
Others who rely on groundwater have private wells that serve fewer households or people than community wells. The most commonly found groundwater standard exceedances in the Rocky River watershed were for iron and manganese. While these do not typically pose a human health hazard, they can discolor water, plumbing fixtures or laundry.
The report on the Chatham County watershed pulls together data, collected by several state and federal natural resource management agencies, to identify trends in groundwater quality and areas of pollution concern. Where water quality is declining, early identification of the contamination sources is essential to preventing long-term damage to the resource, the report states.
The report examines potential natural changes to the groundwater quality from rock formations and soil composition. Rock formations and soil composition are important influences as rainwater soaks into the ground, moves through rock fissures and interacts with minerals before it recharges underground aquifers, or resurfaces as base flow for streams or rivers. The report also assesses the potential impacts to groundwater from human activity such as land use, well-construction practices, agriculture, waste disposal and use of the resource for drinking water and other purposes.
To view the full report, visit the DWQ website at: www.ncwaterquality.org and click on the “Rocky River Groundwater Assessment” link under the heading “DWQ Hot Topics.”