The River Avon /ˈeɪvən/ is an English river in the south west of the country. To distinguish it from a number of other rivers of the same name, this river is often also known as the Lower Avon or Bristol Avon. The name "Avon" is a cognate of the Welsh word afon, "river".
The Avon rises just north of the village of Acton Turville in South Gloucestershire, before flowing through Wiltshire. In its lower reaches from Bath to the Severn Estuary at Avonmouth near Bristol the river is navigable and known as the Avon Navigation.
The Avon is the 19th longest river in the UK at 75 miles (121 km) although there are just 19 miles (31 km) as the crow flies between the source and its mouth in the Severn Estuary. The catchment area is 2,220 square kilometres (860 sq mi).
The name "Avon" is a cognate of the Welsh word afon [ˈavɔn] "river", both being derived from the Common Brittonic abona, "river". "River Avon", therefore, literally means "River River"; several other English and Scottish rivers share the name.
The County of Avon that existed from 1974 to 1996 covering the Avon valley, including Bristol and Bath, was named after the river.
The Avon rises east of the town of Chipping Sodbury in South Gloucestershire, just north of the village of Acton Turville. Running a somewhat circular path, the river drains east and then south through Wiltshire. Its first main settlement is the village of Luckington, two miles (3 km) inside the Wiltshire border, and then on to Sherston. At Malmesbury it joins up with its first major tributary, the Tetbury Avon, which rises just north of Tetbury in Gloucestershire. This tributary is known locally as the Ingleburn, which in Old English means 'English river'. Here, the two rivers almost meet but their path is blocked by a rocky outcrop of the Cotswolds, almost creating an island for the ancient hilltop town of Malmesbury to sit on. Upstream of this confluence the river is sometimes referred to as the 'River Avon (Sherston Branch)' to distinguish it from the Tetbury Branch.
The Town Bridge at Bradford on Avon
After the two rivers merge, the Avon then turns south east away from the Cotswolds and then quickly south into the clay Dauntsey Vale, where it is joined by the River Marden, until it reaches the biggest town so far, Chippenham. The wide vale is now known as the Avon Vale, and the river flows on via Lacock to Melksham, then turns north-west through Bradford on Avon, where the centre of the town grew up around the ford across the river Avon, hence the origin of the town's name ("Broad-Ford"). This was supplemented in Norman times by the stone bridge that still stands today. The Norman side is upstream, and has pointed arches; the newer side has curved arches. The Town Bridge and Chapel is a grade I listed building. It was originally a Packhorse bridge, but widened in the 17th century by rebuilding the western side. On the bridge stands a small building which was originally a chapel but later used as a town lock-up.
The Avon Valley between Bradford on Avon and Bath is a classic geographical example of a valley where four forms of ground transport are found: road, rail, river, canal. The river passes under the Avoncliff and Dundas Aqueducts and at Freshford is joined by the Somerset River Frome. Avoncliff Aqueduct was built by John Rennie and chief engineer John Thomas, between 1797 and 1801. The aqueduct consists of three arches and is 110 yards (100 m) long with a central elliptical arch of 60 ft (18 m) span with two side arches each semicircular and 34 ft (10 m) across, all with V-jointed arch stones. The spandrel and wing walls are built in alternate courses of ashlar masonry, and rock-faced blocks. The central span sagged soon after it was built and has been repaired many times. The Dundas Aqueduct was built by the same team between 1797 and 1801 and completed in 1805. James McIlquham was appointed contractor. The aqueduct is 150 yards (137.2 m) long with three arches built of Bath Stone, with Doric pilasters, and balustrades at each end. The central semicircular arch spans 64 feet (19.5 m); the two oval side arches span 20 feet (6.1 m). It is a grade I listed building, and was the first canal structure to be designated as an Scheduled Ancient Monument in 1951. The stretch of river below and above the aqueduct, where it is joined by Midford Brook, is used by the Bluefriars of the Monkton Combe School Boat Club up to six days a week since at least the 1960s.
Claverton Pumping Station It then flows past Claverton Pumping Station, which pumped water from the River Avon into the canal, using power from the flow of the river. The pumping station is located in a pump house built of Bath Stone, located at river level. Water is diverted from the river by Warleigh Weir, about 200 yd (180 m) upstream. The water flows down a leat to the pumping station, where it powers a water wheel, 24 ft (7.3 m) wide and 17 ft (5.2 m) in diameter, with 48 wooden slats. At full power the wheel uses 2 tons (2 tonnes) of water per second and rotates five times a minute. The water wheel drives gearing which increases the speed to 16 rpm. From here, cranks drive vertical connecting rods which transfer the energy to two 18 ft (5.5 m) long cast iron rocking beams. Each rocking beam in turn drives an 18 in (0.5 m) diameter lift pump, which also take their supply from the mill leat. Each pump stroke raises 50 imperial gallons (230 l; 60 US gal) of water to the canal. In 1981, British Waterways installed two 75 horsepower (56 kW) electric pumps just upstream from the station.
A three arch stone bridge with buildings on it, over water. Below the bridge is a three step weir and pleasure boat.
Palladian Pulteney Bridge and the weir at Bath The Avon then flows through Bathford, where it is joined by the Bybrook River, and Bathampton where it passes under the Bathampton Toll Bridge, joined by the Lam Brook at Lambridge in Bath and then it passes under Cleveland and Pulteney Bridges and over the weir. Cleveland Bridge was built in 1826 by William Hazledine, owner of the Coalbrookdale Ironworks, with Henry Goodridge as the architect, on the site of a Roman ferry crossing. Named after the 3rd Duke of Cleveland, it spans the River Avon at Bathwick, and enabled further development of Georgian Bath to take place on the south side of the river. It was designed by architect Henry Goodridge to take the traffic of his day, horse-drawn vehicles and pedestrians, and was constructed using Bath Stone and a cast iron arched span. Pulteney Bridge was completed in 1773 and is designated by English Heritage as a grade I listed building. The bridge was designed by Robert Adam, whose working drawings are preserved in the Sir John Soane's Museum, and is one of only four bridges in the world with shops across the full span on both sides. It is named after Frances Pulteney, heiress in 1767 of the Bathwick estate across the river from Bath. Pulteney approached the brothers Robert and James Adam with his new town in mind, but Robert Adam then became involved in the design of the bridge. In his hands the simple construction envisaged by Pulteney became an elegant structure lined with shops. Adam had visited both Florence and Venice, where he would have seen the Ponte Vecchio and the Ponte di Rialto. But Adam's design more closely followed Andrea Palladio's rejected design for the Rialto. Pulteney Bridge stood for less than 20 years in the form that Adam created. In 1792 alterations to enlarge the shops marred the elegance of the façades. Floods in 1799 and 1800 wrecked the north side of the bridge, which had been constructed with inadequate support. It was rebuilt by John Pinch the elder, surveyor to the Pulteney estate, in a less ambitious version of Adam's design. 19th-century shopkeepers altered windows, or cantilevered out over the river as the fancy took them. The western end pavilion on the south side was demolished in 1903 for road widening and its replacement was not an exact match. In 1936 the bridge became scheduled as a national monument, with plans being made for the restoration of the original façade. The restoration was completed in time for the Festival of Britain in 1951, with further work being carried out in 1975. Bath and North East Somerset council have discussed plans to ban vehicles from the bridge and turn it into a pedestrianised zone, however it remains open to buses and taxis.
The river is then joined by the Kennet and Avon Canal which connects with the Avon just below the weir at Bath Locks. Together with the Kennet Navigation which joins the River Thames at Reading so providing a through route for canal boats from Bristol to London. From this point downstream it is known as the Avon Navigation.