Peters Brook runs right through the county seat before it reaches the Raritan River, which forms the borough's southern edge. During Floyd in September 1999, Somerville recorded a record 13.34 inches of rain over three days, and the brook and surrounding streets flooded badly even though the storm had weakened by the time it arrived.
Most water problems here are smaller than a once-in-a-generation storm: a basement that seeps every spring, a supply line under a sink, a roof leak in a century-old commercial building. Our phone line is a free connection service, and the work itself is done by independent companies. Call (888) 317-9980 any time and we'll put you in touch with one that serves Somerville.
How the call works: when you call (888) 317-9980, The Restoration Job connects you with an independent restoration provider that serves Somerville. That provider inspects the damage, explains the scope and quotes the work. The Restoration Job doesn't perform restoration itself. Read our referral disclosure.
Peters Brook, the Raritan and Flash Flooding on Local Roads
Somerville's flood risk comes from two directions. The Raritan along the south side rises slowly over a day or more as its North and South Branches deliver water from the hills to the west and north. Peters Brook responds within hours to a heavy thunderstorm, along with the storm drains that feed it.
Ida in September 2021 showed how fast that happens. On the evening of September 1, flooding closed part of State Highway 28 in the borough and shut southbound U.S. 206 near Somerset Street in neighboring Raritan. By 9:20 p.m., storm reports described multiple disabled vehicles and impassable streets. The North Branch of the Raritan near Raritan reached record flooding early the next morning. More than 50 water rescues were carried out across the county that night.
Older Buildings Around the Courthouse and Main Street
The white marble courthouse dates to 1909, and Main Street has kept most of its historic storefronts, many now home to boutique shops, and Victorian architecture shows up along Main Street and in the surrounding residential blocks. Buildings of that age come with specific water problems: galvanized or early copper supply lines, cast-iron drain stacks, stone or brick foundations without modern waterproofing, and attic spaces where ice dams form along old gutters.
Water inside plaster walls behaves differently from water in drywall. Plaster can often be saved if the lath and framing behind it dry properly, so a provider doing water damage repair in an older home should measure moisture inside the cavity before deciding what to tear out.
Winter Pipe Bursts in the Raritan Valley
January lows in Somerville average about 18 degrees, and the county has recorded temperatures as cold as minus 16. Pipes in exterior walls, crawl spaces and unheated porches are the usual failures. Once a pipe splits, water often runs unnoticed until it thaws, so damage can spread across ceilings and into lower floors before anyone sees it.
- Close the main shutoff first; know where it is before winter.
- Open cabinet doors on exterior walls during a deep freeze.
- Keep heat on in vacant units or seasonal properties.
- After a burst, call a plumber for the pipe and a restoration provider for the water, since the two jobs are separate.
Drying Out and Keeping Mold From Starting
July is the wettest month on average in the county, with close to five inches of rain, and summer humidity keeps basements damp even without a leak. That combination is why a wet carpet or soaked box of papers in a Somerville basement can sprout mold within a few days. Structural drying with dehumidifiers and air movers, checked daily with a moisture meter, is the step that prevents most mold problems. If growth is already visible on framing or drywall, removal under containment is the safer route than bleach and a fan.
Tenants, Landlords and Mixed-Use Buildings
Plenty of people in a county seat like this rent, and borough planners have pushed for transit-village housing near the train station. A tenant who finds water should notify the landlord or property manager in writing, photograph personal items and check whether a renters policy is in place, because the owner's policy usually covers the building but not tenants' belongings. Owners of mixed-use buildings should keep a contact list for every unit so they can trace a leak quickly.
Where Callers in the Somerville Area Are
The same line also serves nearby communities such as:
- Raritan
- Bridgewater
- Hillsborough
- Manville
- Branchburg
- Bound Brook
Questions From Somerville Property Owners
Is all of Somerville at risk from the Raritan River?
Risk varies street by street. River flooding is a concern on lower ground near the Raritan on the south side and along Peters Brook. Flash flooding from heavy rain can still affect streets and basements anywhere, as Ida showed in 2021. The FEMA Flood Map Service Center lets you look up the flood zone for a specific address.
Can historic plaster walls be dried instead of removed?
In many cases it can, provided the leak was clean water and the plaster has stayed firmly keyed to its lath. Restoration providers can drill small holes to ventilate wall cavities and track moisture daily. Plaster that has softened, bulged or been soaked by floodwater carrying sewage usually has to come out. Ask the provider to explain their moisture readings before demolition begins.
Where do I get flood warnings for Somerville?
The National Weather Service office in Mount Holly issues flash flood and river flood warnings for Somerset County. The USGS gauge on the North Branch Raritan River near Raritan shows current water levels just upstream of the borough. Signing your phone up for wireless emergency alerts also helps during fast-moving storms.