It is against city ordinance to connect a sump pump to a floor drain, laundry sink, or other drain that empties into the city’s sanitary sewer system. Sump pumps must be connected to a rigid pipe that routes water outdoors. Sump pumps must discharge water from the building to the lawn, street, or storm sewer system. The city will charge a $100 per month penalty for improperly connected sump pumps.
Sump pumps that are illegally connected to the sanitary sewer system result in additional wastewater treatment costs to the city. These types of connections can also cause sanitary sewage to back up into homes and businesses. Illegally connected sump pumps needlessly send clean water to the wastewater treatment plant operated by the Metropolitan Council. According to the Water Environment Foundation, one sump pump can discharge up to 7,200 gallons of clean water per day, which is the equivalent to the flow from 40 average homes.
If your sump pump runs during the winter, there are a number of steps you can take to help manage winter discharge and prevent your system from freezing:
- Remove any flexible discharge hoses. These flexible hoses are not appropriate for winter conditions and may freeze.
- Inspect the sump pump discharge points for any obstructions. Clear any snow or ice accumulation away from the outlet.
- Make sure there is positive drainage around your house.
- Install an underground PVC pipe (or other rigid pipe) to carry the water discharged from the sump pump away from the house.
- Make sure to leave an air gap between the sump pump and the pipe in case of freezing. Place the outlet for the pipe in an area that will not cause a nuisance.
- Ensure that the pipe has a positive slope so water drains through it properly. Any flat sections or dips in the pipe may result in standing water that could freeze and create a blockage.
- If possible, connect your sump pump directly to the city storm sewer system using a PVC line.
- For added protection, run a heat cable through the pipe to prevent water in the pipe from freezing. Select a heat cable that is designed for outdoor use on roofs and gutters, and make sure that the heat cable is recommended for use with PVC pipes. Do not use heat tape that is designed to wrap around pipes as heat tape is not weatherproof.
- Add insulation around the pipes to further protect from freezing.
In some rare cases, site conditions might exist where winter discharge from sump pumps cannot be properly managed. If your sump pump is causing dangerous conditions on public or private property you may submit an application for a permit to temporarily discharge into the sanitary sewer system. The city will review the application and determine if it is appropriate. If approved, permits are valid November 15 through March 15.
Application for Winter Discharge of Clear Water into Sanitary Sewer (PDF)
Plymouth City Hall | 3400 Plymouth Blvd. | Plymouth, MN 55447-1482
P 763-509-5500 | F 763-509-5510 | email@example.com