From: "Malcolm" m.p.schofield@dial.pipex.com
To: penny.maddrell@ntlworld.com; :Brian.Herbert1@tesco.net
Sent: 23 November 2001 10:13
Subject: Re: Flooding
Brian and Penny,
Below are briefing notes compiled by me following the last event.
As your situations either side of the Barton Road are similar in a number of ways, I hope that you will compare notes and progress from time to time. I will keep an eye on Bin Brook and have already arranged for the Ward Ranger (recognisable by his green pullover) to do the same on a regular basis. I will continue to build my knowledge in flood control, although the most that we can all do is to anticipate better and respond quicker.
The most useful information source is the Environment Agency website.
Malcolm
City Council planning responsibilities
1. To reduce and certainly not increase the flood risk.
2. To ensure that flood plains are used for their natural purpose
3. To avoid inappropriate development on undefended flood plain.
4. To apply planning policies on a whole-catchment basis not just flood plain
5. To expect flood risk to increase progressively
6. To apply the precautionary principle to the issue of flood risk.
7. To work with and not against, natural processes in planning future development
8. To recognise that susceptibility of land to flooding is a material planning consideration.
9. To prepare development plans and controlling development, in relation to location and amenity.
Flooding occurs when the amount of water arriving on land and flowing into watercourses exceeds the capacity of the land to discharge that water by infiltration, surface flow, piped drainage or surface watercourses. The limits of flood plains cannot be defined precisely because floods with similar probabilities can arise from different combinations of events. The advantages of flat fertile land, which is easily developed, and managed, have outweighed the disadvantages of intermittent flooding. However the continued construction of hard-engineered flood defences to protect development in vulnerable areas, may not be sustainable in the longer term. Soft engineering such as the creation, preservation and enhancement of natural flood meadows is preferable and can be of great value in its broader contribution.
Impacts have been aggravated by
1. the growth of the built development
2. lack of maintenance of watercourses and culverts
3. building structures that create flood risk both upstream and downstream.
The primary duty for safeguarding land and other property against all natural hazards is with the owner. Advice leaflets in some detail are available from the Environment Agency National Flood Warning Centre e.g. "Sandbags and flood protection products advice for the public" dated 6/11/00. Operating authorities have permissive powers but not a duty to carry out flood defence works in the public interest.
The Environment Agency has a supervisory duty for all matters relating to flood defence in relation to main rivers. Local authorities are the operating authorities for ordinary watercourses, except in internal drainage districts where the powers lie with Internal Drainage Boards. (IDB). An IDB has powers to carry out measures to alleviate flooding in districts with special drainage needs other than main rivers. We do not have an IDB in Cambridge. There are many drainage sites and varied responsibilities, knowledge of which is presently co-ordinated by Alan Wingfield at Mill Rd (Tel 458250) Local authorities have similar powers except in IDB areas. More importantly they are responsible for co-ordinating relief efforts and the preparation of emergency plans. As highways authorities (County Council) they are responsible for draining highways.
There is evidence of an increase in more intense winter rainfall events (as well as experience!). This is in line with a general expectation of a more extreme hydrological cycle with climate change and more extreme precipitation events in the UK. Structure Plans should set out requirements and restrictions regarding the type and form of development that would be acceptable We will certainly be obliged to review and restate Policy NE10 that is limited in its present form. "Development on the flood plain of the River cam and Bin Brook will only be permitted where the applicant is able to demonstrate----- no increase in the risk of flooding or be subject to flooding itself" The need is for more comprehensive planning guidelines/controls and an emergency programme that closes the gap between advice and action.
mps October 2001