Contents Notes |
Alternative wastewater management systems were evaluated for the three small communities of Corning, Furley, and Havana, Kansas. All three communities are rural, agriculturally-oriented settlements with populations of less than 200. Numerous failures of onsite systems have been reported. Soil conditions are such that individual wastewater systems such as septic tank/soil absorption alternatives are not feasible on a widespread basis. The wastewater collection alternatives considered included conventional gravity sewers, small diameter gravity sewers (conveying septic tank effluent), and pressure and vacuum sewers; the treatment alternatives included package plants, spray irrigation, and continuously discharging lagoons. For Corning and Havana, wastewater collection by pressure sewers using individual and clustered septic tank effluent pumps and treatment via continuously discharging lagoons were found to be the most cost-effective wastewater management solutions. Although the pressure sewer collection alternative was also found to be most cost effective for Furley at the projected future population, the cost effectiveness of pressure versus gravity sewers was found to be sensitive to projected growth. It was thus recommended that population projections for Furley be reassessed, which may affect choice of alternatives. Overall, wastewater collection via small diameter pressure conveyance of septic tank effluent was found to be the least costly collection alternative for the three small communities investigated. Compared with various pressure sewer configurations as well as with small diameter gravity sewers, conventional gravity sewers had the highest total present worth cost. |