Northumberland County, Pennsylvania · Sunbury
Water spreading, a burst pipe, sewage, mold or smoke? Call to be connected with a restoration company that serves Sunbury, Shamokin and Milton. Start the steps below while you wait.
Answered 24/7 by a participating local provider. We're a referral service and don't do the work ourselves. How it works
Start here
Pick the closest match. These steps limit the damage and protect your insurance claim. Skip anything that isn't safe.
Pipes freeze in Northumberland County on about 34 nights a year, mostly November to March. Older homes, 55% of the stock here, are most at risk.
Basements flood here mostly in September. Northumberland County averages 7.5 days a year with an inch of rain or more.
Sewage backups in Northumberland County spike on heavy-rain days, about 7.5 a year, when sewer mains fill up and water finds the lowest drain.
Northumberland County's wettest day in the 2015–2024 record brought 3.63 inches, and about 98 freeze-thaw days a year mean ice dams in some winters.
8% of occupied homes in Northumberland County heat mainly with wood or propane, below the Pennsylvania county median of 10%.
With 28 muggy nights a year, mold in Northumberland County can appear within days of a leak. Dry first, then clean.
Local risk profile
With 43,395 homes and around 90,560 residents, Northumberland County is 458 square miles of eastern Pennsylvania. Besides Sunbury, the county seat, the biggest communities are Shamokin, Milton and Mount Carmel. It has some of the oldest housing in the state: the median home went up in 1954.
64/100 Water Damage Risk Index: Elevated Northumberland County ranks 6 of 67 Pennsylvania counties. See the statewide ranking and method.The three factors where Northumberland County ranks highest compared with other Pennsylvania counties.
For frozen pipes, Northumberland County is a typical Pennsylvania county, which is still plenty. In the 2015–2024 record the county logged about 34 nights a year at or below 20°F (40th of 67) and 120 below freezing. Twenty degrees is roughly where uninsulated pipes start to freeze.
Cold snaps are the real risk. The worst in the record lasted 15 days below freezing (ending January 2018), and the low bottomed out near -7°F on February 24, 2015.
The freeze season here runs November to March, with January the coldest. If you travel then, leave the thermostat at 55°F or above and open sink cabinets on outside walls.
On average the first fall freeze arrives around Oct 26 and the last spring freeze around Apr 25.
Rainfall is about average for Pennsylvania. Of roughly 43.9 inches of yearly precipitation, the damage comes from the 7.5 days a year with an inch or more, ranked 27th of 67. April, September and October see the most. The single wettest day in the record: 3.63 inches, September 2, 2021. Multi-day storms matter most for basements; the wettest three days on record here totaled 7.1 inches (through July 26, 2018).
The temperature crosses 32°F in both directions on roughly 98 days a year. Each cycle melts and refreezes water at roof edges and in foundation cracks, which is how ice dams and basement seepage get started.
Housing
Pennsylvania's 67 counties range widely in housing age; Northumberland ranks 9th, with 77% of its homes built before 1980.
55% were built before 1960. Homes from that era often still have galvanized steel supply pipe, which rusts from the inside until it pinholes, and cast iron drains that crack with age. Slow leaks behind walls are a common start to water damage in these houses.
Beyond water
About 28 nights a year in Northumberland County stay at 65°F or warmer, a sign of muggy summer air (21st of 67 counties). July is the wettest month. Keep indoor humidity under 60%, as the EPA advises, and dry any leak within 24 to 48 hours; in a humid month a wet basement left alone won't dry by itself.
Mold remediation: what to expectBy main heating fuel, Northumberland County homes break down as 27% utility gas, 30% electric, 5% propane and 3% wood. Fires here are likelier to start in the kitchen or the wiring than in the furnace. After any fire, keep the HVAC off until ducts are checked, or soot will travel through the house.
Fire and smoke cleanup: first stepsCoverage
Calls connect to restoration companies that work across Northumberland County. The largest communities by population:
Population from ACS 2020-2024 5-year estimates. Townships and unincorporated areas are covered too.
Nearby
Columbia, Lycoming, Montour, Schuylkill and Union get more pipe-freeze nights than Northumberland. Schuylkill County has the oldest housing nearby, with 79% of homes built before 1980.
By the numbers
| Factor | Northumberland | Pennsylvania median | Rank |
|---|---|---|---|
| Homes built before 1960 | 55% | 42% | 8 of 67 |
| Homes built before 1980 | 77% | 66% | 9 of 67 |
| Homes built 2000 or later | 8.6% | 13% | 59 of 67 |
| Manufactured or mobile homes | 4% | 6.6% | 50 of 67 |
| Vacant homes | 13% | 12% | 30 of 67 |
| Wood or propane heat | 7.7% | 10% | 48 of 67 |
| Nights at 20°F or colder | 34/yr | 37/yr | 40 of 67 |
| Days with 1 inch+ of rain | 7.5/yr | 7/yr | 27 of 67 |
| Freeze-thaw days | 98/yr | 98/yr | 33 of 67 |
| Muggy nights (65°F+) | 28/yr | 16/yr | 21 of 67 |
Rank 1 is the highest value. Bars run from the lowest to the highest Pennsylvania county; the tick marks the median; orange means higher water damage risk than the median, green means lower.
Questions
Peak risk months in Northumberland County: freezing from November to March, heavy rain in April, September and October.
Sources: U.S. Census Bureau, ACS 2024 5-year estimates (2020-2024); weather from NOAA nClimGrid-Daily county averages (EpiNOAA), 2015–2024, averaged across the county; county boundaries from Census TIGER. Reviewed 2026-10-21. Methodology