Compton Lock, by-weir and Bridge 60

MATERIALS: the lock chamber and tail bridge are constructed of weathered orange brick with blue brick and ashlar dressings; timber gates with balance beams hinged from concrete collar blocks.

PLAN: the lock chamber has a rectangular plan with splayed flanking walls at either end.

DESCRIPTION: the lock chamber is closed at the head by a top gate equipped with a single gate paddle. The gate is flanked on either side by paddle posts that control the main flow of water through culverts into the lock chamber. The curved stone cill beneath the gate is laid on a scalloped brick base. The pair of mitred lower gates are each equipped with a gate paddle and the balance beams are provided with a modern brick-paved ginny ring. A tubular metal water depth gauge is attached to the western wall of the chamber; three secondary square timber bollards and two cast iron button-topped bollards remain to either side.

The top pound narrows rapidly on the eastern side of the approach to the lock and is faced with a brick flanking wall with a cast-iron rubbing strake attached. On the opposite side, a brick-lined overflow culvert directs water to a circular ‘morning glory’ by-weir, built of brick with sandstone capping stones. The drain in the centre of the by-weir has a modern grill, and it is protected from the towpath by a low brick parapet wall. A secondary rectangular concrete spill weir is situated between the brick-lined culvert and the short flanking wall that leads to the top gate. Slots for a temporary timber coffer dam exist in the splayed flanking walls of the top gate. The lower flanking walls splay at slightly different angles, the eastern wall has old brick coping and a cast iron rubbing strake, while the western wall was re-built and paved in 1986 using blue brick.

The lock tail bridge is integral to the lock structure, situated directly above the tail of the lock chamber. The top (northern) side of the bridge has a low parapet wall with stone end blocks. The southern elevation of the bridge is battered and waisted with some secondary brick patching on the eastern side. The three-centre brick arch has ashlar jambs, springers, and a drip mould above the brick voussoirs. Above the level of the arch, the face of the wall is carried up vertically to form the bottom parapet with large semi-circular blue brick coping stones, some of which have been replaced in sandstone. The carriage way that originally allowed access to a lock keeper’s cottage (now demolished), has been partially re-laid in brick paving; a concrete date stone set into the paving reads - ‘Rebuilt 1986 British Waterways Board’. The western end of the bottom parapet wall plunges in a curve to a flight of steps leading down to the bottom pound. Beyond the steps, a re-built retaining wall supports the towpath as it descends to the lower level, and the spill weir culvert emerges from beneath in the canal wall.