Sewage in your basement is something a homeowner never hopes to see and hopefully one that a homeowner in Holland won't see thanks to our separated sewer system.

A separated sewer system contains one set of sewer pipes (storm sewers) carry surface water and excess groundwater to lakes and streams with little to no treatment and another set of sewer pipes (sanitary sewers) carry the residential, commercial and industrial sewage to our Wastewater Treatment Plant prior to being discharged to Lake Macatawa.

So can raw sewage enter my home during a rain event?

Technically, no, but some of the pipes in our 190-mile sewer system have cracks that can allow groundwater to enter. HBPW has a routine program of monitoring, repairing and replacing pipes. Rainwater can also enter through some manhole covers. Groundwater and surface water can also enter through any joints in private sewer services, which are the responsibility of the customer.

Raw sewage can also come from illegally connected foundation drains and sump pumps improperly connected to the sanitary sewer. These could have been connected because a storm sewer pipe was not yet connected, or they were too deep to connect the storm sewer in the street, which is typically shallower than the sanitary sewer.

Wondering how this adds up?

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!

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.

We want to help!

We want to help you identify whether your basement footing drains and/or your sump pump is connected to the sanitary sewer.

Call us today at 616.355.1643 to schedule a free, 15 minute inspection.


A city ordinance is in place to help address the illicit connection issue. Find the ordinance details here.