Roach & Crouch
The Roach and Crouch estuary complex drains into the Outer Thames Estuary between two areas of reclaimed marshes; the Dengie Peninsula to the north and the islands of Foulness, Potton, and Wallasea to the south. Anthropogenic changes to the estuarine complex have resulted in the combination of the Roach and Crouch estuaries into a single system that flows into the sea between the Thames and the Blackwater estuaries. As a result the estuary channel is heavily constrained and at risk of flooding. Any future development of flood defences within the estuary should enhance the natural estuary development, where possible.

The Roach and Crouch estuaries converge at Wallasea Ness some 5km upstream from the mouth of the estuary. The Crouch extends for approximately 24km before reaching its tidal limit at Battlesbridge. The Roach extends for approximately 14km before reaching its tidal limit at Rochford and has numerous tributary creeks along its length.

The estuary complex consists of relatively deep, narrow channels with limited intertidal margins. This is due to the reclamation of intertidal areas. The estuary suffers from poor 'flushing' on the low ebb tides resulting in the deposition of sediment and a decrease in channel depth. The flood embankments make this problem worse, as they further constrain the estuary processes. As tidal velocities increase erosion becomes a dominant feature of the estuary channel, placing considerable stress on existing flood defences.

The condition of the existing flood defences range from 'generally poor' to 'relatively good'. However, estuarine processes and the rising sea-levels are placing added pressure on the defences. Given the wealth of assets within the estuary flood plain, the need for flood defence management is imperative. The Roach and Crouch Flood Management Strategy will identify the most appropriate way of managing flood defences within this estuary complex. Given the historic impacts of human activity in this area, future flood management must progress in a sustainable manner.

Assets at Risk
Within the 12,100ha of coastal floodplain surrounding the Roach and Crouch estuaries, there are a significant number of assets at risk of flood damage, including over 2,700 properties, 9,560ha of typically high-grade agricultural land and 168km of flood defences.

There are many properties spread across the flood plain in numerous sparse settlements, villages and in the principal towns of Burnham-on-Crouch, Rochford and South Woodham Ferrers. The Ministry of Defence owns a significant portion of the land and assets at risk within the boundaries of the Shoeburyness Estate.

Some of the flood defences constructed along the banks of the Roach and Crouch Estuary have included contaminated material, with high costs associated with their removal and safe disposal. Historic industrial works have also created potential pollution hazards within the flood risk area.

Freshwater habitat sites of international importance are found within the area at risk from salt water flooding, and these would typically be expected to require protection under the Habitats Directive. However, as the condition of these sites is variable, and the creation of additional salt marsh is also a requirement, English Nature has been consulted to identify those sites that must be protected from salt water, and those which may be compensated for by the creation of similar (or better) habitats further upstream, where they will be more sustainable in the long-term.