Sewage Treatment System Management Using GIS
Bob Brems, MPH
333 Putnam Ave.
Zanesville, OH 43701
Ed Shaffer, RS
205 N. 7th St.
Zanesville, OH 43701
Sewage treatment systems are utilized extensively in rural areas of Muskingum County, Ohio to manage wastewater from households that do not have the option of connecting to a municipal system. Muskingum County has over 10,500 existing systems and over 300 new systems are installed each year. To better manage alterations to existing systems and construction of new ones, a GIS was implemented.
Utilizing an existing Mircosoft Access data set of sewage treatment system information, and spatial data generated by the Muskingum County GIS department, all sewage treatment system locations were geocoded using ArcGIS 9.0. Now, utilizing parcel information, soil composition, and land contours, sanitarians are able to perform preliminary sewage treatment system reviews in minutes and eliminate the need to review printed parcel maps located in another building, and usually at least one site visit. The resulting map was made accessible to all sanitarians on the computer network using ArcPublisher.
As the population in southeast Ohio continues a steady movement from cities to rural areas, the extension of public sewers has not kept pace. In many cases extending public sewer to remote or sparsely populated areas is not economically feasible. As a result, the individual sewage treatment system has taken a prominent place in the overall practice of sewage treatment, and is utilized extensively throughout Muskingum County, Ohio.
The first step in the design of a home sewage treatment system is to determine the suitability of soils. Most home treatment systems depend on soils to both treat and absorb wastewater. Factors such as soil permeability, depth to seasonal ground water, bedrock or other limiting layers, surface topography, and the flow of runoff water all must be evaluated in determining the suitability for an on lot sewage treatment system.
The most common, and economical, type of system consists of a septic tank followed by a series of leaching lines. The tank serves as primary treatment. It allows for the settling and storing of most of the solids and starts the anaerobic breakdown of the wastewater. The leaching lines disperse the wastewater over a large area allowing further treatment and absorption by the soil. Other types of systems have been developed to overcome limitations of the soil, or to operate on smaller home sites. These systems include aeration, filtering water through sand, peat or other material, and chemical disinfection.
Muskingum County, Ohio has over 10,000 existing systems of record and over 300 new systems are installed each year. To better manage alterations to existing systems and new installations, a GIS was implemented which enables ZMCHD sanitarians to quickly assess a property’s suitability for a sewage treatment system.