The areas covered by International, European and National nature conservation designations, and extent of the Indicative Flood Zone for the different Management Units are illustrated in the downloadable pdf files.
CPU1 Pagham Beach to Selsey East Beach, Selsey - Area of general shingle accretion, including spits across Pagham Harbour. Fed by northerly longshore drift and onshore transport from inter-tidal banks. Also some longshore feed from north due to local drift reversal. Breach of spits would damage sensitive environments in Pagham Harbour and could cause extensive flooding of farmland, holiday developments and other property. Area has major environmental assets and some backshore residential development at Pagham Beach.
CPU2 East Beach to West Beach, Selsey - Area of natural headland erosion controlled by seawalls, groynes and beach recharge. Some beach feed from nearshore banks. Drift divide at headland of Selsey Bill. Seawall condition variable to west, parts being in private ownership. Serious overtopping occurs along most of the Unit. Breach of east facing defences would result in flooding of residential areas and open ground. Land levels behind southwest facing defences are above maximum water level.
CPU3 West Beach, Selsey to Bracklesham - Area of general erosion of shingle ridge and lower foreshore, with exposures of soft formation of Bracklesham Clays, plus short lengths of eroding soft cliffs at south end of ridge. Some beach feed from southeast and some from nearshore banks. Breach of ridge would flood extensive areas of farmland and holiday development plus some homes. Continued erosion of cliff may outflank ridge, causing extensive flooding, and may also cause loss of residential property along western limit of Selsey. Beach and backshore includes environmental assets.
CPU4 Bracklesham to East Wittering - Area of soft cliff erosion controlled by seawalls, breastworks and groynes. Some beach feed from south east. Overtopping damage along wall, but little damage to residential areas behind the first line of properties. Foreshore lowering taking place slowly but will cause overtopping and beach erosion in the long-term.
CPU5 Cakeham Estate to East Head - Area of soft cliff erosion extending into eroding shingle ridge and sand dunes. Groynes and short sections of gabions and breastwork control erosion. Residential area set back from shoreline in east. Potentially floodable farmland behind ridge to west. Some beach feed from south east.Lower beach extends out to 2km wide low tide East Pole sand bank.Complex sand transport around bank due to influence of strong currents in Chichester Harbour entrance.
CPU6 Sandy Point to the Inn-on-the-Beach, Hayling Island - Low-lying residential area built on eroding shingle foreland.Main frontage protected by sea wall fronted by a recharged beach. Unstable shingle spit extends up Chichester Channel. Drift divide causes erosion at Eastoke. Overtopping of wall or breach of spit will cause flooding.
CPU7 Inn-on-the-Beach to Langstone Harbour Entrance, Hayling Island - Area of shingle accumulation, with a spit extending to the Ferry in Langstone Harbour. Subject to cyclic variations, but long term trend is erosion to the east, accretion at Gunner Point and erosion/accretion to Langstone Ferry. Shingle beach west of the Inn-on-the-Beach protected by timber sloping revetment. Miscellaneous seawalls along the spit facing into Langstone Channel, some subject to damage.
CPU8 Langstone Harbour Entrance, Hayling Island to Southsea Castle, Portsea Island - Low-lying land protected by shingle beach, and spit extending into Langstone Harbour. Area of minor erosion south of Hayling Ferry, major accretion at Eastney and relative stability at South Parade. Gabions and timber groynes protect the spit facing into Langstone Harbour. Concrete walls form a hard defence around Fort Cumberland. Future beach erosion could result in overtopping of seawall/promenade with flooding of residential or recreational land, opposite Lumps Fort and east of Southsea Castle.
CPU9 Southsea Castle to Portsmouth Harbour Entrance, Portsea Island - Southsea and Old Portsmouth once protected by shingle beach, though this is greatly reduced due to waterfront development since the C15th. Seawalls extend around Southsea Castle and to the Royal Naval War Memorial. Masonry walls protect Old Portsmouth and have historic importance. Long term beach losses are small. Risk of coastal flooding to high density urban development.
CPU10 Portsmouth Harbour Entrance, Portsea Island to Fort Gilkicker, Gosport - Massive revetment (Haslar Seawall) protects MoD property as well as low lying land.Low beach levels. Potential breach or overtopping near Fort Monckton. Littoral drift along this frontage is now very low. Seawall and embankment protect low-lying lagoon near Fort Gilkicker. Narrow shingle beach with groynes fronts the wall. Breaching of the embankment would cause flooding of the lagoon and loss of rare habitat.
CPU11 Fort Gilkicker to Browndown Ranges - Area of shingle accretion with its apex at Gilkicker Point. Limited supply of beach material to the area due to construction of coast protection works to the northwest at Lee-on-the-Solent and Hill Head. Erosion at the north-western end of Browndown Ranges. Slow accretion continues to take place west of Gilkicker Point. Much of the backshore is undeveloped and has major environmental and recreational assets. Short section of road protected by wall is subject to erosion and overtopping. The River Alver outfall crosses the beach and is subject to blocking by shingle.
CPU12 Lee-on-the-Solent to Hill Head Harbour - Frontages of clay cliffs, with pockets of low lying land. Mainly a residential area. Littoral drift from the northwest is interrupted by Hill Head Harbour with shingle swept onto nearshore banks and sand transported offshore by tidal currents. Outfalls also affect drift. There are stretches of seawall and a number of groyne systems. Some areas on the Hill Head frontage have no built protection.
CPU13 Hill Head Harbour to Solent Breezes - Frontage of eroding cliffs of clay, sand and gravel. Low lying land is restricted to Titchfield Haven in the southeast. Seawalls, timber groynes and timber and sheet steel piling provide erosion and flood protection at Titchfield Haven. Cliff erosion provides material for the spit along the Titchfield Haven frontage. There is a drift divide at Solent Breezes in the north west.
CPU14 Solent Breezes to Hook Lake - Frontage of eroding cliffs of clays, sand and gravel feeding Hook Spit to the northwest. Cliff protection at Solent Breezes consists of a short length of gabion and timber bulkhead. National Grid have major infrastructure north of Solent Breezes at risk from erosion and flooding.