Sump pumps must not drain into sewers or septic tanks Spring rainfall means household sump pumps will begin discharging water and now is the time to check hoses and plumbing systems to make sure the water is not pumped into the household sewer line, said Charles H. Ullery, Extension water and natural resources specialist from South Dakota State University.
Adding large volumes of sump water overloads the system that treats the sewage, said Ullery. This is true for individuals dependent on their own private septic tanks as well as for community sewage treatment plants or lagoons used by cities and towns.
Both septic tanks and community treatment systems are designed to handle and treat normal volumes of sewage from houses. Ullery said the addition of volumes substantially greater than this can result in incomplete treatment of the waste with the following negative effects:
* For community systems this may result in polluted streams as non-treated water is discharged or lagoons overflow.
* For septic tanks, the drainage field may be overloaded and polluted water enter wells or appear as a wet spot on the land surface.
A typical modern home produces 75 to 125 gallons of sewage per resident each day, said Ullery. For a family of four producing average amounts of sewage, about 400 gallons is produced by a typical house or apartment.
Should the house have a sump that discharges one gallon of water per minute, an additional 1,440 gallons of water is added to the waste treatment system.
"That sump water results in four times more water entering the sewage treatment system. Treatment systems cannot function properly when this volume of water is added for sustained periods," Ullery said.
Ullery recommends that sump pump hoses and pipes discharge their water on the land surface at least 25 feet away from the houses. Further is better and the hose or pipe outlet must always be located down-slope from the house if possible. Discharging the water down-slope and away from the house assures the water won't recycle back into the sump systems.
Many towns and cities have rules and ordinances prohibiting sump water from being discharged into sewer lines.