Starling (structure)

In architecture, a starling (or sterling) is a defensive bulwark, usually built with pilings or bricks or blocks of stone, surrounding the supports (or piers) of a bridge or similar construction.

Starlings may be shaped to ease the flow of the water around the bridge, reducing the damage caused by erosion or collisions with flood-borne debris or river traffic.

Depending on their shape and location, some starlings may accumulate river debris, mud and other objects, potentially creating navigational hazards or hindering downstream water flow.

The cutwater may be of concrete or masonry, but is often capped with a steel angle to resist abrasion, focusing force at a single point to fracture floating pieces of ice striking the pier.

In cold climates, the starling is typically sloped by about 20 to 45° from vertical, so current pushing against part-submerged ice tends to lift and shear it;[2] this can be known as a starkwater.

The starlings of Tower Bridge , London, are clearly seen beneath the roadway.
Old Wye Bridge, Chepstow , low tide, looking upstream.
Middletown–Portland railroad bridge , Connecticut: starlings on the bridge piers and at each end of the swing span (the fence-like structures around the piers are pile-supported bridge fenders ).
Refuges on Baslow Bridge , Derbyshire.