Why a sewer backup is a contaminated loss
Sewer water carries waste, so it is handled, removed and cleaned in a stricter sequence than clean water.
Water from a sewer line is not safe to handle with bare hands or to leave on porous materials. The crew uses protection for the work, and it removes carpet, pad, insulation and any drywall that held the water, because those materials cannot be cleaned to a safe standard. Hard surfaces are cleaned and then disinfected with a product suited to wastewater.
The point of the strict sequence is that a room is left in a state where it can be dried. A room that is cleaned but not dried grows mould, and a room that is dried but not cleaned keeps the contamination. The crew does both, in order, and it records each step.
What a Milwaukee backup looks like after a storm
After a heavy storm, the lowest rooms fill first, and the damage is often confined to the floor, the wall base and the stored contents.
In Milwaukee the July 2010 storms showed how quickly lower levels can fill. The water entered through floor drains, fixtures and window wells, and it stood in the lowest rooms until the sewer drained. Many houses lost their carpet, their stored boxes and their lower drywall, while the upper floors were dry.
That pattern is the one the crew looks for. It starts the scope at the lowest point and works upward, measuring the wall base and the subfloor on the way. The line of the water on the walls is recorded, and it becomes the boundary of the removal.
- Note the height of the water line on each wall
- Check stored boxes, shelves and appliances for contamination
- Check the floor drain and the connection to the sewer
- Check the furnace and water heater for water at the base
- Record the time the water was first seen and when it stopped
Stopping a backup from returning
The source is found first, and any backflow protection is discussed with a plumber.
Cleaning a backup does nothing if the sewer water can come back. The crew traces the flow to find the path the water took, and it notes whether a backwater valve is fitted, whether it is working and whether a floor drain is connected to a line it should not be. A plumber or the sewer authority is the right party to fit or repair any valve.
The homeowner should not wait for the crew to finish before asking about the source. A written note of the source and the plumber's advice goes into the file, and it is the basis for any later decision about backflow protection.
- Find the path the water took from the sewer
- Check whether a backwater valve is fitted and working
- Note any floor drain connected to the wrong line
- Ask a plumber to advise on backflow protection
- Keep the plumber's note with the scope
The sequence of the first visit
The first visit confirms the source, the power and the area, then sets the removal and drying plan.
On the first visit the crew confirms the power is off, identifies the source and the rooms affected, and takes readings in the subfloor and at the wall base. It then sets the removal list and the drying target. The homeowner is given the plan before the removal starts, and the removal is recorded item by item.
The second and later visits check the readings against the target. A room that is not drying to target is re-examined, because a sewer backup can leave wet material in the wall cavity that the first reading did not reach.
- Confirm the power is off in the lower level
- Identify the source and the rooms affected
- Take readings in the subfloor and at the wall base
- Set the removal list and the drying target
- Check the readings against the target on each visit
Protecting the homeowner during the clean-up
Protection is worn by the crew and by anyone who stays near the work, and children and pets stay out.
Sewer water is a health concern, so the homeowner should keep children and pets out of the work area and wash hands after any contact with the water or the wet material. Clothing that touched the water should be washed separately, and shoes that touched it should be cleaned before they come indoors.
The crew wears the protection the work requires and keeps the work area sealed where it can. It does not work near open flames or with power on in a wet room.
- Keep children and pets out of the work area
- Wash hands after any contact with the water
- Wash clothing that touched the water separately
- Clean shoes before they come into the rest of the house
- Keep the work area sealed where practical
