Homeowner guide · Storms and basements
Sump pumps and backwater valves: a Tredyffrin and Easttown guide after Ida
A reliable basement defense in T/E has four parts: a sump pump sized for your pit, a battery backup for power outages, a working check valve, and a discharge line that carries water well away from the house. Homes that took sewer water through floor drains in 2021 should also ask about a backwater valve.
Key takeaways
The short version
- Storms and power outages tend to arrive together, so a battery backup matters.
- A failed check valve lets pumped water run back into the pit.
- Test the pump before spring and fall storm seasons.
- Groundwater and sewer backflow are different problems with different fixes.
- Many municipalities do not allow sump pumps to drain into the sanitary sewer; confirm with your township.
What 2021 taught T/E basements
In August 2021, Tropical Storm Fred dropped about 4 inches of rain in an hour and a half. On September 1, Ida brought more than 8 inches to the region. A wall along Trout Creek collapsed and the creek flooded the Gateway Shopping Center, and wet vacs sold out as homeowners across the townships bailed out basements. Afterward, Tredyffrin residents packed public meetings about flooding.
Storms like those exposed the same weak points again and again: pumps too small for the water coming in, pumps that stopped when the power went out, check valves that had failed, and floor drains that let sewer water back into the house.
The four parts of a reliable sump system
1. A properly sized primary pump
The pump has to move water faster than it enters the pit during a heavy storm. If yours runs constantly in ordinary rain or struggles to keep up, it may be undersized or near the end of its life.
2. A battery backup
Heavy storms often knock out power, and a plug-in pump stops exactly when you need it most. A battery backup pump sits in the same pit and takes over automatically when the primary fails or loses power.
3. A working check valve
The check valve on the discharge pipe keeps pumped water from flowing back into the pit when the pump shuts off. When it fails, the pump cycles on and off repeatedly and wears out faster.
4. A good discharge route
Water should leave the pipe well away from the foundation and flow away from the house, not pool against the wall and seep straight back into the pit.
Choosing a backup: what to compare
Battery backup systems vary more than most people expect. These are the questions that matter when choosing one for a T/E basement.
Runtime
How long the battery can keep pumping during an outage, which depends on battery size and how often the pump has to run. Outages during big storms can last many hours.
Alarm and monitoring
Most backups sound an alarm when they take over or when the battery is low. Some can send an alert to your phone, which matters if you travel.
Fit in your pit
The backup usually sits beside the primary pump in the same pit. A small pit can limit your options, so we measure before recommending a unit.
Battery maintenance
Batteries wear out. Know how old yours is and check it as the maker recommends.
How to test your sump pump
- Check power: make sure the pump is plugged in and the breaker is on.
- Fill the pit: slowly pour a bucket of water into the pit until the float rises.
- Watch it run: the pump should start, empty the pit, and shut off cleanly.
- Check the discharge: go outside and confirm water is leaving the pipe.
- Listen after it stops: water rushing back into the pit suggests a failed check valve.
- Test the backup: unplug the primary and repeat, if your backup allows it.
Test before spring and fall storm seasons, and after any long period when the pump did not run.
Warning signs your sump pump needs attention
- Runs constantly, even in dry weather
- Cycles on and off rapidly
- Makes grinding, rattling, or humming noises without pumping
- The float sticks or tangles against the pit wall
- Visible rust or corrosion on the pump or pipes
- Water in the pit rises higher than it used to before the pump starts
- Your backup battery has not been replaced in years
Groundwater vs. sewer backflow: know which one you have
Not all basement water is the same, and the fix depends on where it comes from.
| What you see | Likely source | Usual fix |
|---|---|---|
| Clear water seeping at the floor edge or rising in the sump pit | Groundwater | Sump pump, battery backup, check valve, better discharge and grading |
| Dirty or smelly water coming up through a floor drain or basement fixture | Sewer backflow | Backwater valve, and a camera inspection of the sewer lateral |
| Water only when the washer or shower upstairs runs | Blocked main drain | Drain cleaning and a camera inspection |
| Water near the water heater | Tank leak or relief valve discharge | Water heater inspection or replacement |
A backwater valve installed in the building drain lets wastewater flow out but closes to keep sewer water from flowing back in during extreme events. It needs to be installed correctly and kept accessible for maintenance.
Where can a sump pump drain?
Sump pumps are meant to handle groundwater, and many municipalities do not allow them to be connected to the sanitary sewer, because clean water entering the sewer adds load to pumping stations and treatment plants. That matters in Easttown, where sewage flows through thirteen pumping stations before leaving the township.
If your sump pump discharges into a laundry sink, floor drain, or sewer pipe, confirm with your township whether that is allowed, and consider rerouting the discharge outside.
During a storm or outage
- Keep people away from standing water near outlets and appliances
- If the primary pump stops, check the breaker and plug before anything else
- Gently lift the float to see if a stuck float is the problem
- If the power is out, rely on the battery backup and conserve its runtime by limiting water use
- If sewer water appears in floor drains, stop using all fixtures in the house
For a failed pump with water rising, see our emergency plumbing page and call.
A note on insurance
Water from a sump pump failure or a sewer backup is often treated differently from other water damage, and some policies require a specific endorsement to cover it. Read your policy or ask your agent before storm season, not after. Photograph any damage right away and keep receipts for cleanup.
Help your sump pump from the outside
The less water that reaches your foundation, the less your pump has to move. A few outdoor fixes reduce the load before storm season.
- Keep gutters and downspouts clear
- Extend downspouts so they release water well away from the house
- Make sure soil slopes away from the foundation
- Keep window wells clear of leaves and debris
- Check that the sump discharge line is not frozen, crushed, or clogged
When to call
Pump failed, or planning a backup before the next storm?
We install sump pumps, battery backups, check valves, and backwater valves across T/E. Call (610) 788-0042.
Frequently asked questions
Sump pump and basement questions
Answers by John, Tredyffrin Easttown Plumber.
Do I need a sump pump battery backup?
If your basement relies on a sump pump, a battery backup is strongly worth considering. Storms and power outages tend to arrive together, which is when a plug-in pump stops working.
How often should I test my sump pump?
Before spring and fall storm seasons, and after any long period when it did not run. Pour water into the pit and confirm it starts, empties the pit, and shuts off.
What does a sump pump check valve do?
It keeps pumped water from flowing back into the pit when the pump shuts off, which prevents rapid cycling and extra wear.
What is a backwater valve?
A valve in the building drain that lets wastewater flow out but closes to stop sewer water from flowing back into the house during extreme events.
Can my sump pump drain into the sewer?
Many municipalities prohibit connecting sump pumps to the sanitary sewer. Confirm with your township, and route discharge outside and away from the foundation.
Why does my sump pump run all the time?
Possible causes include a high water table after heavy rain, a failed check valve, a stuck float, or an undersized pump. If it runs in dry weather, have it checked.
How long do sump pumps last?
It varies with how often the pump runs and the quality of the unit. Pumps that run constantly wear out sooner. Test regularly, and plan a replacement when the pump shows warning signs rather than waiting for it to fail in a storm.
Our service area
Plumbing across Tredyffrin Township, PA
Tredyffrin Easttown Plumber serves every neighborhood in Tredyffrin Township, including Wayne, Strafford, Chesterbrook, Paoli, Berwyn, Devon, Daylesford, and Howellville, plus neighboring Easttown Township. Our office is at 217 Conestoga Rd, Suite 10, Wayne, PA 19087.