The Holland BPW operates and maintains nearly 190 miles of public sanitary sewer main.  These sewer mains are scheduled to be cleaned on a 5-year rotation.  The Holland BPW also has a robotic camera that is remotely operated from a van that can enter all of these sewers and inspect them.

Sewer cleaning is done by inserting a high pressure hose into the sewer.  The jets on the hose are angled and propel the hose down the length of the sewer.  As it is pulled back, it drives any debris that collects in the sewer towards a downstream manhole.  There, the Holland BPW's Vactor truck sucks the debris into a truck.

From time to time during this cleaning process, your home or business may experience a hint of sewer gas or there may be some gurgling of the water in your toilet.  A home with properly operating plumbing should not have any issues since the pressure from the hose line should be relieved through the vent stack that is on your plumbing.  The vent stack is a required element of your plumbing system to vent the sewer gas from your home and all of your drain fixtures should be connected to it.  It may be plugged with a bird's nest, snow, leaves or other debris.  One method to clear a possible blockage is to flush the vent stack with a hose from the roof.  The photo to the right is of a vent stack extending through a roof.

Another way for sewer gas to enter your home or business is through a dry trap.  Each open drain is required to have a trap that holds a little bit of water in it which prevents sewer gas from entering the home.  During our routing cleaning process, that water may have been sucked out of the trap if the vent stack was partially blocked.  Be sure to pour water down each and every open drain every now and again to prevent the water in the trap from drying up.

Below is a diagram of a trap under a sink.