Thames riverbank design, planting and living walls

See index page for Chelsea to Tower Thames Landscape Strategy

Most of the Thames in Central London has been embanked. This has narrowed the water channel and greatly reduced are of riverside habitat - in Roman times the river was much wider and its banks were wetland marshes. Today, the banks of the Thames in London are, with a few exceptions, flanked by either (1) vertical walls (2) sloping revetments.

Most embankments have been single-purpose engineering projects and, except green algae (eg Enteromorpha, which flourishes on porous surfaces) are largely without green plants. These walls could be converted to green living walls without undue trouble or expense. The ownership and control of the banks is as follows:

1. The Port of London Authority owns the riverbed (except for small areas near royal palaces).
2. The Environment Agency is responsible for monitoring the condition of the riverbanks and has concerns for biodiversity, archaeology, recreation and visual quality. But it does not have budgets to promote these objectives. The EA has published guidance on riverbank design in a report on Partnership in Planning.
3. Landowners holding public and private property adjoining the river also own the riverbanks and are responsible for their maintenance.
4. Planning control (under the Town and Country Planning Acts) provides many opportunities for improving the design of the riverbanks, because many riverside sites are being re-developed. These powers should be used to effect visual, social and ecological improvements to the design of the riverbanks and river walls. Works can include green walls, ecological terracing, timber fendering, slipways, river steps and riverside walks.

Re-development of riverside property is an almost-continuous process. This has resulted in great changes of all kinds above the statutory flood defence level (5.41m in the City of London) and, except from an engineering standpoint, very few improvements below this level. The explanations are as follows:

1. The Port of London Authority, as a navigation and safety authority, has little or no interest in other design objectives.
2. The Environment Agency does not have funds for the improvements it would like to see.
3. Landowners have no incentive to spend money on anything except the 'bare necessities' below the flood defense level.
4. Planning control has been used unimaginatively, with the authorities using what funds they have been able to extract from developers for social housing and transport projects.