Christchurch Harbour
Christchurch Harbour is a natural harbour in the county of Dorset, on the south coast of England named after the nearby town of Christchurch.
Two rivers, the [River River Avon, Hampshire|Avon, Hampshire|Avon] and the [River River Stour, Dorset|Stour, Dorset|Stour], flow into the Harbour at its northwest corner. The harbour is generally shallow and due to the tidal harmonics in the English Channel has a double high water on each tide. On the north side of the harbour, east of the Avon are Priory Marsh, and to the east of this Stanpit Marsh, a Local Nature Reserve. To the west side of the harbour are Wick Fields, the southern flank of the harbour being bounded by Hengistbury Head, a prominent coastal headland.
The harbour flows into the Christchurch Bay and the English Channel through a narrow channel known locally as The Run which rests between Mudeford Quay and Mudeford Spit. Shallow-draught boats can enter from this channel and cruise up stream for choosing either the Avon or the Stour, the Stour leading up as far as Iford Bridge passing Christchurch Quay and Tuckton.
Christchurch Harbour Site of Special Scientific Interest is a site designated both for its biological and geological interest. It comprises the estuary of the Stour and Avon and the Hengistbury Head peninsula. The varied habitats include saltmarsh, wet meadows, grassland, heath, sand dune, woodland and scrub. The site is of great ornithological interest.
History
The harbour was formed around 7000 years ago when the sea level rose at the end of the last ice age. Previously the area which was many miles from the open sea was inhabited by Stone Age hunters. Archaeological finds dating from 12,500 year BP have been made on Hengistbury Head and Flints dating as much as 250,000 years BP have been found in the Bournemouth area. The Bluestones used at Stonehenge may have been transported via the harbour and the River Avon. It is suggested that there may have been an ancient causeway usable at low water running from Double Dykes on the south shore to Tuttons Well located on the north shore near Stanpit village.The Harbour became a major trading port around 100BCE, exports included copper, gold, silver and iron and importing luxury goods including wine and glass from which jewellery was manufactured. It is likely that slaves were also exported through the harbour. The boats used at this time were shallow draft, oak-planked with square leather sails for propulsion. It would have been a twelve-hour passage across the channel to Cherbourg and without any modern compasses or much weather forecasting. Despite this there was considerable two way trade with both British and Foreign Ports, it then declined as a result of the Roman invasion of France in 56 BCE. The remains of a Roman ship were discovered in the harbour in 1910. Trade continued until the Roman Invasion of Britain in AD43. During Saxon times the harbour again became one of the most important in Britain as it was easily reached from the continent and boats could enter the harbour and travel up the river Avon all the way to Salisbury, and along the Stour to Wimborne and Blandford Forum.
In 1664 The River Avon Navigation act was passed to again enable vessels to travel as far as Salisbury and reestablish it as a port as in medieval times. Traffic used the river from 1684 to 1720 with a break whilst repairs were made from 1695 to 1700. The route was finally abandoned in 1730. In 1695 Lord Clarendon made a new entrance in Mudeford Sandbank using the iron stone from Hengistbury to form a training bank, these rocks now called Clarendon Rocks are still in existence, but the new entrance silted up and the channel returned to its original course. During this period and up until the middle of the 19th century, smuggling was rife in the Harbour.
There were numerous Harbour Improvement schemes proposed in the next three centuries, particularly the Railway and Docks Scheme of 1885. This would have seen major dredging of the harbour, training banks within the harbour and a railway terminus on the south side. In 1965 there were a plans to construct a marina at Wick Hams. This and the other schemes were never proceeded with. In the 1930s there were three "tea boats" providing refreshments to holidaymakers and at least another five houseboats in the harbour these were all abandoned and then wrecked during World War II. The River was dredged in 1937 and again in the 1950s using a Suction Dredger, in the late 1980s Wessex Water carried out substantial dredging in the River Stour from Iford bridge as far as Christchurch Quay, this was part of a Flood Alleviation Plan. The channel has been marked since at least 1884 first by Christchurch Sailing Club and since 1963 by the Harbour Improvements Association now renamed Christchurch Harbour Association. Since 1963 the Mudeford inshore lifeboat has been stationed on the quay at Mudeford.
Geology
The Harbour is made up of Sandy Gravels, Sands, Muddy Sands, and towards the margins Silty Muds.High and low Salt marsh both exist within the harbour, the latter colonised by Puccinellia and other grasses. Spartina anglica does not exist in significant volume, with no sign that it was previously extensive. The sedimentation of the Harbour has not therefore been substantially affected in the way most other south coast estuaries have by the spread and die back of this species. Any loss of the salt marsh appears to have been offset by the re-colonization of abandoned artificial salt pans. Extensive Phragmites reed beds occupy tidal creek margins and areas of higher marsh, where they front wet grazing meadows. The inflow and outflow of sediment in the Harbour is positive,. Grimbury Marsh, is substantially composed of dredged spoil material. In total the estuarine system is a sediment sink.