Rain gardens and rain parks

See index page for Chelsea to Tower Thames Landscape Strategy

Rain gardens and rain parks can contribute to the Thames Landscape Strategy. Both have floodable areas which detain and infiltrate water when it rains.  These areas can be dry in dry weather or they can have a permanent water area which becomes deeper and larger in wet weather. Such places can be beautiful and wildlife-friendly but from an urban stormwater management perspective they key function is that of prevent rainwater entering drains. This policy has many benefits:

• storm water detention saves money on building drains
• storm water detention prevents combined sewers from becoming overloaded in storm conditions - at which time they discharge raw sewage into the Thames and its tributaries
• stormwater infiltration  recharges the aquifers from which half of London's water supply is obtained
• stormwater detention and infiltration helps prevent flooding

When these facilities are designed as surface amenities on private property they are called rain gardens. When located in public open spaces they can be called rain parks.

Rain parks

Some public parks and public open spaces are well-suited to stormwater management and it can be an addition source of income for the park managers. The money which would otherwise be spent on drains, or on the Thames Tideway Tunnel, can instead be spent on making rain parks. The sight of flooded land is beautiful and interesting but design measures are required to make sure that they are not a safety hazard.