Onondaga Creek runs through Syracuse, and the city says its channel has less capacity than before because of sediment and that intense short-duration storms add to the flood risk. A basement near the creek can take water from a storm even without an overflow, so the entry points and the FEMA panel for the address matter most.
Key takeaways
- The city attributes higher flood risk on Onondaga Creek to lower channel capacity from sediment and to intense short-duration storms.
- The six-mile city section of the creek is engineered for combined sewage and storm flows, much of it lined with concrete.
- FEMA's 2016 maps expanded the Special Flood Hazard Area on the creek by 175 acres and added hundreds of structures to the regulated floodplain.
- A basement can take creek or storm water through a window well, a door, a bulkhead or a drain, and each entry leaves a different mark.
- The city lists separate FEMA maps for the creek, Harbor Brook, Ley Creek, Meadowbrook and Onondaga Lake, so the panel for the address is what decides the zone.
- Before the next storm, clear the window well, check the drains and photograph the basement so that any water line can be compared afterwards.
What makes the creek a risk to a Syracuse basement?
The creek's risk comes from less channel capacity, because of sediment, and from storms that deliver a lot of rain in a short time. The city names both causes in its floodplain material, and a basement near the creek can see the effect even when the water stays inside the channel.
A creek channel needs room to carry its flow. When sediment builds up in it, the space for the water shrinks, and the water reaches the banks at a lower flow than before. The city describes that as the reason its flood risk on the creek has grown, and it is the first thing a homeowner should understand about the creek.
The second cause is the storm. An intense short-duration storm drops a large volume of rain on the ground in a few hours. The ground cannot take it in and the channel cannot carry it away, so the water moves over the low ground and into the streets and yards near the creek.
Why does a storm reach a basement before the creek overflows?
Storm water reaches a basement through the openings nearest the ground, such as window wells, doors, bulkheads and floor drains, long before the creek rises over its banks. The creek sets the level of the water table and the storm drains, and the openings decide where the water enters the house.
A basement is a low point of the house. Water that stands in the yard or runs along the street will find the lowest opening it can reach. The creek does not need to overflow to fill that opening, since the storm can back water up the drains and across the ground before the creek reaches the bank.
This is why two basements a few houses apart can take water in the same storm. The one with the lower opening, or with a window well that overflows, takes the water first, and the other stays dry until the storm is larger.
| Entry point | How water arrives | What the crew records |
|---|---|---|
| Window well | Water collects in the well and runs down the wall behind the glass | The water line on the wall and the well's condition |
| Door or threshold | Water runs across the yard and under or over the sill | The sill, the threshold and the floor in front of it |
| Bulkhead | Water flows down the bulkhead steps into the room | The steps, the wall at the base and any debris |
| Floor drain | Water rises through the drain when the line or the street is full | The drain's position and the line's condition |
| Foundation crack or porous wall | Water seeps through the masonry during a long wet period | The crack, the stain and the wall readings at several heights |
What do the FEMA maps change for a creek-side home?
The FEMA maps set the flood zone for each address. FEMA's 2016 maps expanded the Special Flood Hazard Area on Onondaga Creek in Syracuse by 175 acres and added hundreds of residential and commercial structures, so a home that was outside the regulated area may now be inside it.
The panel for an address shows whether the property sits in the Special Flood Hazard Area. Inside that area, the floodplain rules apply to any repair, and the insurer's flood terms are more likely to matter. Outside it, the risk is lower but not zero, since water can come from storms that a map does not model.
The city's floodplain page lists separate maps for Onondaga Creek, Harbor Brook, Ley Creek, Meadowbrook and Onondaga Lake. A creek-side home should check the panel for its own address, not the one for the next street, because two addresses can sit on different panels.
What should you check before the next storm?
Before a storm, check the window well, the drains, the sump and the lowest door, and clear debris from the yard near the entry points. Photograph the basement as it is, so that a later water line can be compared with a known starting condition.
Clear the window well of leaves and debris, and check that its cover or grate is in place. Keep the yard drain or catch basin near the house clear, so the water can run toward the drain rather than to the door. A sump pump, if one is installed, should be tested and its discharge kept clear.
Take dated photographs of the basement's walls, floor and entry points. If the basement floods, those photographs show the change from a known condition, which is the most useful record for an insurer and for a crew.
- Clear the window well and check its cover or grate
- Keep the yard drain near the house free of leaves
- Test the sump pump and keep its discharge clear
- Photograph the basement walls, floor and entry points now
- Note the FEMA panel number for the address
What should you do during a creek-driven storm?
During a storm, stay out of moving water, keep the power off to a flooded area until an electrician confirms it is safe, and call a crew if water is entering the house. Do not wait for the creek to overflow before you act, since the basement can take water from the storm first.
Move valuables up off the floor and out of the lowest room if it is safe to do so. Close the door to the basement to slow the spread of water into the rest of the house, and keep a phone charged and a number for the crew to hand.
If water is already entering, call the crew and tell the dispatcher where the water is, how deep it is and which entry it is coming through. That description helps the crew bring the equipment it needs on the first visit.
What should you do after a creek flood in the basement?
After a creek flood, remove the standing water and the silt, dry the wall base and the framing, and record the water line and the entry point. The water is contaminated, so protective equipment is needed for each step, and the openings are recorded for the insurer.
The crew removes the bulk water and the silt before the drying equipment is set. The wall base is read at several heights, since creek water can soak into masonry and stay there after the floor looks dry.
The owner should keep the readings, the photographs and the list of removed materials. Those documents show the work done and answer the questions an insurer or a floodplain office will ask.
How do the city's maps and the insurer fit together?
The city's maps tell the owner the zone and the floodplain rules, while the insurer decides the claim under the policy. The two are separate questions, and an owner should answer both before the rebuild is designed.
A homeowner who wants to know whether the basement is inside the Special Flood Hazard Area should check the FEMA panel for the address and the city's floodplain page. A homeowner who wants to know whether the policy pays for creek water should read the flood terms and ask the insurer to explain them in writing.
The New York State Department of Financial Services is the state regulator for insurers. A dispute about how the claim is handled can be raised with it, and the homeowner should keep the insurer's letters with the readings and the panel number.
How should a Syracuse owner keep a basement record for a future buyer?
A basement record is a dated set of photographs, panel numbers, readings and repair papers kept together. A buyer, a lender or an insurer who asks about a creek-side basement can then see what happened, when and what was done about it.
Start the record with the photographs taken before any storm, then add each water event as it occurs. Each event should carry its date, the water line, the entry point, the crew's readings and the list of removed materials. A single folder or a single digital file is enough, provided the entries are complete.
Keep the FEMA panel number and the date it was checked, since the zone can change when the maps are revised. Add the permit answers from the city or the office that covers the property. A buyer will ask these questions, and a record that answers them directly is worth more than a verbal account.
The record also helps the owner's own decisions. A basement that takes water from the creek side every few years is a candidate for work on its entry points, and the record shows which entry to address first. Use the same photographs and readings to test each change over the next storms.
Frequently asked questions
Does the creek have to overflow for my basement to flood?
No. Storm water can reach a basement through its low openings before the creek overflows, and the city attributes higher flood risk on the creek to sediment and to short intense storms.
What does the FEMA panel for my address tell me?
It shows the flood zone for the address, including whether the property is inside the Special Flood Hazard Area. The panel decides which floodplain rules apply to a repair.
Is a creek basement always a flood risk?
Being near the creek adds to the risk, but the entry points and the lowest opening matter more for a particular basement. A crew reads the building and the openings before it says where the water came from.
Should I buy flood insurance?
That is a decision for the owner, with the insurer and the policy terms. Standard homeowner policies often exclude flood water, so ask the insurer what coverage it offers and read the terms in writing.
What is the single most useful thing to do before a storm?
Take dated photographs of the basement and clear the window well and the yard drain near the entry points. The photographs give a known starting point, and the cleared openings reduce the chance of an easy entry.
Sources
- City of Syracuse – Floodplains
- FEMA – Flood Maps
- New York State Department of Financial Services – Consumer Assistance
This guide is general information for Onondaga County homeowners, not a substitute for an on-site inspection. Prices are estimates. See our disclaimer.