As you are likely aware, heavy rain events in the area over the last few years have caused some homes in our community to have sewage enter their homes through their basements. This of course should not happen since the Holland area has a separated sewer system. A separated sewer system is one in which one set of sewer pipes (storm sewers) carry surface water and excess groundwater to lakes and streams with little to no treatment, and a second set of sewer pipes (sanitary sewers) carry the residential, commercial and industrial sewage to the Holland Area Wastewater Treatment Facility prior to being discharged to Lake Macatawa.
“How could raw sewage enter homes during rain events? The sanitary sewer should not have rain water in it!”
That is absolutely correct. Unfortunately, some of the pipes in our 190-mile sanitary sewer system have cracks in them and that allows groundwater to enter. Rainwater may also enter through some manhole covers. We have a routine program of monitoring, repair and replacement to address these problems. Ground water and surface water can also enter through any of joints in private sewer services which are the responsibility of the customer.
Another major source of clean water comes from illegally connected foundation drains and sump pumps of homes improperly connected to the sanitary sewer. They were likely connected because there wasn’t a storm sewer pipe yet to connect them to or they were too deep to connect to the storm sewer in the street which is typically shallower than the sanitary sewer.
A typical ⅓ or ½ Horsepower (HP) sump pump can discharge 50 gallons per minute (GPM). If the sump pump runs for a combined total of 5 hours a day, every day, that can contribute as much as 15,000 gallons of clean water per day to the sanitary sewer system that does not need to be treated. That’s nearly 5½ MILLION gallons per year!
Many years ago, the City of Holland addressed the problem of clean water entering the sanitary sewer system by passing the following ordinance:
Sec. 29-43. Discharge of waters not containing sewage prohibited; corrective action; lien for services.
(a) No person shall discharge, or cause to be discharged, any storm water, surface water, groundwater, roof runoff, subsurface drainage, uncontaminated cooling water, or unpolluted process water to the sanitary sewer system.
(b) If a connection to the sanitary sewer is found to exist, the property owner shall be responsible for separating the connection and shall perform all corrective repairs to comply with the provisions of this section.
(c) If the property owner fails to separate the connection from the sanitary sewer system, the city shall be permitted [to] enter onto private property in order to separate the connection and make any necessary installation or construction. The city shall recover from the property owner a fee (as determined by the BPW) for separating such service or device. If such fee is not paid within sixty (60) days after the demand has been made by the city, that amount shall constitute a lien on the property and shall be subject to foreclosure and enforcement in accordance with the statutes of this state.
Ground water and storm water do not require the same treatment process as the sanitary sewer system. The treatment process alone at the Wastewater Treatment Plant costs as much as $1.15 per 1,000 gallons of water.
Please view 
THIS FILE for a schematic of a typical home sewer configuration that is properly connected.
The Holland BPW wishes to help you identify whether your basement footing drains and/or your sump pump are connected to the sanitary sewer. Please call us at the number below to schedule an appointment for an inspection. There is no cost to you for this inspection which should take no more than 15 minutes.
Please feel free to contact us with any questions or concerns between 7:30 AM and 4:00 PM at 616.355.1643.