Basement Waterproofing in Amherst, NY

A town built on the bottom of Lake Tonawanda

Nearly all of Amherst lies on the low plain that a New York State Geological Association field guide (Young and Briner, 2006) identifies as the bed of glacial Lake Tonawanda, a shallow lake roughly 58 miles long that lingered between the Onondaga and Niagara escarpments until about 9,000 radiocarbon years ago. The Erie County soil survey describes what it left behind: a broad, nearly flat plain where streams meander with low gradients and, in the survey's words, there are numerous swampy areas. Ellicott Creek, which the survey calls the main drainageway north of Buffalo, crosses the town on its way to the Niagara River, and Tonawanda Creek forms the northern edge.

The survey's type locations for several lake-plain soils are in Amherst, which tells you what is under the lawns. Cosad loamy fine sand was described from a site off Dodge Road: a sandy mantle over lake-laid clay, with a perched water table sitting above the clay from late fall through spring. Getzville silt loam, described near Tonawanda Creek Road, is poorly drained with a silty clay loam subsoil. Elnora loamy fine sand, from a site near Klein and Transit Roads, is the better-drained sandy soil that occupies the slight rises. Where a house sits on the sand over clay, water moves fast to the foundation and then stops.

Housing from the 1950s through the 1970s, and its foundations

The Census Bureau's 2024 American Community Survey one-year estimate for the town of Amherst counts about 58,000 housing units. Only around 8 percent predate 1940; roughly 15 percent were built in the 1950s, about 19 percent in the 1960s and about 18 percent in the 1970s, with construction continuing at a slower pace since. That makes Amherst a town of concrete block and poured concrete foundations, most of them with a basement, and many of them with a clay-tile or early plastic footing drain that has had fifty or sixty years to silt up.

The block houses of Eggertsville and Snyder, the ranches and splits of the Sheridan Drive and Maple Road corridors, and the larger poured-wall homes of East Amherst each show their own pattern. Block walls on the wet flats fill with water and leak at the bottom course; a horizontal crack a few courses below grade means the saturated sand and clay outside has begun to push. Poured walls in the newer sections leak at shrinkage cracks and the cove joint. In both, water at the floor edge in March is the Lake Tonawanda water table coming up through the slab.

What works in Amherst

Because the ground is flat and the water table is high, the reliable fix for a wet floor edge in Amherst is an interior perimeter drain at the footing with a sump sized for sustained spring inflow. Block walls get weep holes into the drain so they cannot hold water. Poured-wall cracks are injected. Where an original footing drain still exists, we check whether it can be cleared; more often it is bypassed by the new interior system.

Amherst has separate storm and sanitary sewers, and sump discharge belongs in the yard or the storm system, not the sanitary line. Sump discharge lines here need a freeze-relief fitting and a graded run, because a line that freezes in January on a flat lot has nowhere to drain. On the sandy soils near Dodge and Transit Roads, a properly built dry well can take sump and downspout water; on the clay flats it will not, and the line has to reach daylight or the street.