The human version (we wrote this, not the council)
This section introduces the environment chapter. The district takes its name from the Rivers Colne, Chess and Gade, which meet at Rickmansworth, and with the Grand Union Canal and many former quarry lakes the area has a complex flooding picture and a wide floodplain. Three Rivers faces flood risk from rivers, surface water, groundwater, sewers and reservoirs, and climate change is expected to increase that risk. At the same time the district lies in one of the driest parts of the UK, so development must be flood-safe and use water efficiently.
An unofficial plain English summary. The official wording below is
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The text below is extracted automatically from the official PDF and may
contain artefacts; the PDF is authoritative.
10 Environment
Flood Risk and Water Resources
10.1 As the name of the district suggests, there are several significant watercourses
flowing through the district. The three rivers referred to in the name of the district are
the River Colne, River Chess and River Gade, with their confluence at
Rickmansworth. With the addition of the Grand Union Canal running parallel to the
rivers and a number of large lakes, mainly formed as a result of sand and gravel
quarrying, the area around Rickmansworth has a particularly varied range of water
bodies, leading to a comp lex flooding picture and a wide floodplain, running from
south-west Watford to the south through Rickmansworth and to the south west corner
of the district near Maple Cross and West Hyde. However, a significant area of ‘flood
plain’ is in fact occupied by the linear pattern of lake formations running parallel to
the River Colne. Three Rivers is at risk of flooding from all sources, namely rivers,
surface water, groundwater, sewers and reservoirs and the effects of climate change
are predicted to increase the risk of flooding in the district.
10.2 Despite this, Three Rivers is located in one of the driest parts of the UK, with
Hertfordshire’s average rainfall returning only two-thirds of the national average.
10.3 Due to the potential impacts of climate change and the increasing pressure for
development across the district, it is vital that developments are safe and resilient to
the risk of flooding, that water quality is enhanced and that development makes
efficient use of