Why is storm water treated differently from a sewer backup?
Because storm water comes from the street and the yard, and it is usually not carrying waste, but it still needs drying and it still needs a clear source.
A storm line carries rain from roofs, driveways and streets to an outfall or a creek. It is not built to carry the contents of a house. Water that backs up through it is therefore a different category from a toilet or a sanitary line, and the cleanup is shaped by that difference: the water can usually be pumped, dried and rinsed in place rather than treated as a hazard.
The difference is not a reason to leave it. Storm water in a garage sits on the slab and wicks into the wall base, and it can carry mud and leaves that rot if they are left. A clean-looking backup can still leave a damp slab and a damp wall that read wet a week later, so the drying is done as carefully as it would be for any other water loss.
Which drain belongs to whom, and who clears what?
The homeowner clears the drain on the property, while the street inlet, the county line and any subdivision drain belong to the office or association that owns them.
The first question on a backup is which part of the line is blocked. A garage drain and a yard inlet on the lot are usually the owner's to keep clear. The line running under the street, the county culvert and any drain in a common area are not, and those are reported to the office or association that maintains them rather than cleared by the homeowner.
This page does not state which office owns which pipe in Snellville, because the property record decides that for each address. The owner can ask the county or the city which drains serve the lot, and the answer is written down, since it decides who answers the next backup.
What should be done in the first hour after the water comes back?
Keep the water out of the rest of the house, photograph the drain and the line, and stop anyone walking through the wet floor.
The first hour is about containment. A rug or a cardboard box in a wet garage is moved onto a dry surface, a cord that lies in the water is unplugged where that is safe, and the door to the rest of the house is shut. The water line on the wall is photographed while it is visible, and the drain is photographed with the grate and the water around it.
Anything that was set down in the water is lifted. The time the backup started, the time the rain stopped and the time the water was first seen are written on the same photograph, because the sequence matters when the drain office asks about the storm.
- Move rugs, boxes and stored items off the wet floor onto dry surfaces
- Unplug cords that lie in the water only where that can be done safely
- Shut the door to the rest of the house to keep the water from spreading
- Photograph the drain, the grate and the water line with the time written down
How is a lower room or garage dried after a storm drain backup?
The slab and the wall base are read for moisture, and the finish is opened where the readings show the water wicked up.
Storm water that stands on a slab wicks up into the drywall and the sill plate at the wall base, and it can run under the baseboard into the next room. The readings are taken at the slab, along the wall base at a few heights and at the sill, so that the wet edge is mapped rather than guessed. The map sets the line where the finish is cut open to dry the cavity.
A slab that has been flooded is dried from the air side as well as the surface. Fans across the floor, a dehumidifier in the room and doors open to the rest of the house move the moisture out. The drying is judged by the readings, not by the look of the floor, because a slab can feel dry on top while its underside is still damp.
- Map the wet edge along the wall base with a moisture meter
- Open the baseboard and the lowest course of drywall where the wicking shows
- Run air across the slab and the cavities behind the finish
- Record readings at the start, at intervals and at the end
What is left to fix once the drain is working again?
The drain itself, the grade that sends yard water toward it and the finish that was opened for the drying.
A garage drain that backed up is checked for a blockage that can be cleared with a rod or a flush, and for a trap or a backflow valve that has failed. A yard inlet that keeps filling is a grading problem as much as a drain problem, and the water it collects is often coming from a slope that sends the yard toward the garage.
The finish is replaced only after the wall base and the slab read normal. The owner is advised to keep the photographs and readings with the record, because the next backup will be checked against them.
