Blakeney Point - Coastal Changes

Coastal Changes

The spit is a relatively young feature in geological terms, and in recent centuries it has been extending westwards and landwards through tidal and storm action. This growth is thought to have been enhanced by the reclamation of the salt marshes along this coast in recent centuries, which removed a natural barrier to the movement of shingle. The amount of shingle moved by a single storm can be "spectacular"; the spit has sometimes been breached, becoming an island for a time, and this may happen again. The northernmost part of Snitterley (now Blakeney) village was lost to the sea in the early Middle Ages, probably due to a storm. In the last two hundred years, maps have been accurate enough for the distance from the Blakeney Chapel ruins to the sea to be measured. The 400 m (440 yd) in 1817 had become 320 m (350 yd) by 1835, 275 m (300 yd) in 1907, and 195 m (215 yd) by the end of the 20th century. The spit is moving towards the mainland at about 1 m (1 yd) per year; and several former raised islands or "eyes" have already disappeared, first covered by the advancing shingle, and then lost to the sea. The massive 1953 flood overran the main beach, and only the highest dune tops remained above water. Sand was washed into the salt marshes, and the extreme tip of the point was breached, but as with other purely natural parts of the coast, like Scolt Head Island, little lasting damage was done.

Landward movement of the shingle meant that the channel of the Glaven was becoming blocked increasingly often by 2004. This led to flooding of Cley village and the environmentally important Blakeney freshwater marshes. The Environment Agency considered a number of remedial options. It concluded that attempting to hold back the shingle or breaching the spit to create a new outlet for the Glaven would be expensive and probably ineffective, and doing nothing would be environmentally damaging. The Agency decided to create a new route for the river to the south of its original line, and work to realign a 550 m (600 yd) stretch of river 200 m (220 yd) further south was completed in 2007 at a cost of about £1.5 million. The Glaven had previously been realigned from an earlier, more northerly, course in 1922. The ruins of Blakeney Chapel are now to the north of the river embankment, and essentially unprotected from coastal erosion, since the advancing shingle will no longer be swept away by the stream. The chapel will be buried by a ridge of shingle as the spit continues to move south, and then lost to the sea, perhaps within 20–30 years.