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Map centred on the Rainham Marshes policy unit boundary. This is on the north bank of the River Thames and extends from the Beam River in the west to Mardyke in the east. It includes Rainham, the Rainham Marshes site, and part of the River Ingrebourne towards Hornchurch. The flood risk layer shows some areas of the policy unit, including parts of the marshes, have a 0.1% or higher chance of flooding each year. Defences reduce the risk of flooding.

Description

The Rainham Marshes policy unit extends from the River Beam in the west to Mardyke in the east. It includes extensive freshwater marshes, the Royal Society for the Protection of Birds (RSPB) Rainham Marshes site and part of the River Ingrebourne towards Hornchurch.

The councils responsible for this area are:

• London Borough of Havering
• Thurrock Council

The waterways in the area include:

• Thames tributaries including the River Beam, the River Ingrebourne and the Mardyke
• Havering Sewer
• drainage systems on Rainham, Aveley and Wennington marshes

Local areas at risk and types of flooding

The areas at risk of flooding include:

• Rainham Marshes Nature Reserve
• a large landfill area
• major transport links, including the A13 and the HS1 railway

The types of flooding that could affect this policy unit include:

• tidal flooding when the tide overtops flood defences
• fluvial flooding from the Thames and its tributaries Ingrebourne River, the Mar Dyke (West Bank) and the Beam River (East Bank) - when heavy rainfall causes rivers to overflow their banks or defences
• fluvial flooding from local watercourses including Havering Sewer and the marsh drainage systems on Rainham, Aveley and Wennington marshes
• a combination of these

In the policy unit alongside the marshes there is a large landfill area and major transport links, including the A13 and the HS1 railway, which are at risk of flooding.

Managing flood risk in this area

To manage these risks, the flood defences include:

• tidal flood defences downriver of the Thames Barrier
• fluvial flood defences on the Mardyke and River Beam
• the Beam Washlands fluvial flood storage area, a pumping station to pump fluvial flood flows into the Thames
• a tidal sluice to prevent tidal water flowing upstream on the River Beam

There are also drainage system outfalls with tidal sluices to prevent tidal water flowing upstream on:

• Havering New Sewer
• River Ingrebourne
• Rainham Main Sewer

Flood risk from the River Ingrebourne is relatively low.

The marshland drainage system will also need enhancing as sea levels rise and storm rainfall increases. This could include outfall improvements and local fluvial flood storage.

The tidal sluices will need upgrading on the River Beam, Havering New Sewer, River Ingrebourne and Rainham Main Sewer as the sea level rises and fluvial flows increase.

The Environment Agency uses flood alerts and flood warnings to inform people about potential flooding so they can take appropriate action.

Sign up to receive flood warnings in your area.

Flood risk management policies for this area

Thames Estuary 2100 sets flood risk management policies for each area of the estuary. The policies range from P3 to P5 and outline how we should manage that areas tidal defences.

The flood risk management policy for this area is P4.

This means we will take further action to keep up with climate and land use change so that flood risk does not increase. We will need to work with other risk management authorities to do more to manage flood risk.

Find out more about flood risk management policies.

Local requirements: who needs to do what

Tidal flood defence owners

By 2040tidal flood defence owners in this policy unit should:

• work with the council, developers and local infrastructure providers to adapt defences and achieve multiple benefits through proposed development
• work with the Environment Agency to raise defences where required

For further information read outcome 2: improving fixed flood defences.

Local councils

There is currently no riverside strategy for this area. By 2030, councils should work with communities to plan how their riverside will look in future.

Find out more about the riverside strategy approach.

Network Rail

Network Rail will work with councils and the Environment Agency to ensure transport infrastructure in Essex is resilient to increasing flood risk. This will support growth in the outer estuary.

Thames Estuary Partnership

The Thames Estuary Partnership will work with communities, councils, the Environment Agency and other partners to update the Thames Strategy East. This landscape vision for the river corridor will include a riverside strategy approach to tidal flood defence upgrades.