Flooding Matters. Introduction

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1 Flooding Matters 19/07/2013 Issue 1 Introduction Hello and welcome to the 1 st Essex County Council flood and water management newsletter, Flooding Matters. As a Lead Local Flood Authority we now have responsibilities to management surface water and act as a point of contact. Through the Essex Partnership Flood Management we aim to create a network of commutations between different parties, to better surface water management. To aid communion the puddle will be produced quarterly to keep you up to date with progress within our team and other areas related to our work. Ordinary Watercourse: South Essex By Lee Sencier Since January ordinary watercourse consent application have been received ranging from piping short length of a ditch through to dealing with treatment of watercourse on larger development. We have also received 60 ordinary watercourse enquiries predominantly relating to the flooding of ordinary watercourses. Other enquires received also related to unconsented works, fly tipping and overland flooding. Some example of work carried out since January includes: Christmas period of It was concluded that this came about as a result of flooding from a nearby Ordinary Watercourse. We have consulted with local residents and parish councils about the problem and are in the process of liaising with stakeholders including Private Landowners, Essex Highways and Network Rail in determining an appropriate solution. Manor Trading Estate, Benfleet: One property experienced severe internal flooding and several others external flooding as a result of the heavy rainfall over the Christmas period. Some of the factors contributing toward this included unconsented backfilling of drainage ditches and poorly maintained road infrastructure/ watercourses. We are in the process of consulting with all relevant stakeholders including Private Landowners, Anglian Water, The Environment Agency and Essex Highways in determining an appropriate solution Cadogan Avenue, West Horndon: Multiple properties on Cadogan Avenue were flooded as a result of heavy rainfall over the Ordinary Watercourse - Eight Ash Green, Essex 1

2 Surface Water Management Plans (SWMP) By Jo Carrington A SWMP is a study undertaken in consultation with key partners to understand the cause and effects of surface water flooding and agree the most cost effective way of managing surface water flooding in the long term. A SWMP will investigate local flooding issues that occur as a result of heavy rainfall from: Runoff from land Groundwater Sewers/drains Small watercourse/ditches (ordinary watercourses) Following a processes of identification and prioritisation six SWMPs have been undertaken by Essex County Council in collaboration with key partners such as local councils, the Environment Agency and utility companies. Currently SWMPs cover the urban areas of Harlow, Maldon & Heybridge, Chelmsford, Colchester and Brentwood; a larger SWMP called the South Essex SWMP covers the districts of Basildon, Rochford and Castle Point. With the exception the SE SWMP, which is already complete, the remaining five SWMPs are due for completion by the end of July Two new SWMPs are proposed to start this year, one in Loughton and one in Braintree. Once SWMPs are complete and areas at high risk from surface water flooding are identified, partners look for synergies across organisations and start to prioritise schemes for future implementation to reduce local flood risk to communities where it is technically and financially viable. All identified schemes are placed on the Medium Term Plan (MTP) which is submitted to the Environment Agency so they can be considered for future funding along with other schemes from across the UK for the central government s Flood Defence Grant in Aid funding (FDGiA) and also Local Levy (LL). Linda imagery technique used in SWMP analysis 2

3 Property Level Protection (PLP) By Danny Jennings PAGE 3 PLP measures increase the resilience of individual properties against flood water inundation by creating physical barriers at entry points to a property such as temporary flood door and window barriers, airbrick covers and non-return flow valves on water pipes. PLP surveys have been undertaken at sites affected by main river flooding where bids to Defra on behalf of the Environment Agency provided funding, and also at least one site affected by local flood risk where we have agreed to undertake surveys to understand the cost of options to protect property from flooding along with findings of hydraulic modelling work. Door barrier in operation ( The information on potential costs of PLP measures will need to be presented to flood affected communities, and the partnership, which will need to make important decisions on whether individual property measures should be funded over flood defences. Since January 2013, PLP surveys have been undertaken at; Designs of a permanent airbrick cover ( Broad Green, Steeple Bumpstead main river flooding Sible Hedingham main river flooding Little Waltham main river flooding Rawreth main river flooding Church End Lane, Runwell Two types of barriers in operation ( Testing of flood barrier and flood food (HR Wallingford) 3

4 Flood Investigation since January By Danny Jennings Following the wet conditions during 2012, particularly at the end of November and over Christmas, a number of flood incidents satisfied the criteria for formal flood investigations. Where we have undertaken a formal flood investigation, and where engineering judgment determines that a flood issue cannot be resolved without further more detailed flood risk information, we are producing hydraulic modelling. This will enhance our understanding of flood risk in an affected area, suggest measures to reduce the flood risk and provide evidence for Defra (and Partnership) funding bids. The modelling is similar to that undertaken in SWMP areas so where a flood investigation site is within a SWMP area then modelling would not be progressed. Formal Flood Investigation Reports have been published on our website for flooding at; Old Mead Lane, Henham (Uttlesford District) April 2013* Lower Road, Little Hallingbury (Uttlesford District) April 2013 Danbury Vale, Danbury (Chelmsford Borough) June 2013* White Elm Road, Blenheim Close, Peartree Lane, Bicknacre (Chelmsford Borough) July 2013* Old Mead Lane, Hanham Flooding at Danbury Vale Three further formal investigations are on-going and reports are expected to be published in the next few months; Church End Lane, Runwell (Chelmsford Borough) July 2013* Wilsons Lane/Godmans Lane, Marks Tey (Colchester Borough) July/August 2013 Stondon Massey (Brentwood Borough) August/September 2013 * Sites where hydraulic modelling is underway. We are also continuing to investigate numerous other sites across the county where the criteria for a formal investigation haven t been fully satisfied but property has been affected. This is helping to identify causes of flooding, such as blocked watercourses or pipes, which can be easily rectified and reduce the likelihood of an incident which might trigger the formal flood investigation criteria during a heavier spell of rain. The success of a flood investigation is only possible with the full support and sharing of information from all members of the partnership. Drainage asset information is a source of information that can enhance the understanding of how an area should, and therefore isn t, draining, and can reduce the need for expensive intrusive investigations. Often resolution of a flood investigation is only possible 4

5 Flood Investigation Case Study Ash Tree Cottage By Nicola China and Danny Jennings Late 2012 early 2013 experienced some of the heaviest rainfall on record. A property on Old Wickford Road, South Woodham Ferrers experienced flooding in late November The resident had resided at the property for 32 years and encountered flooding in 2009, but had no issues prior. The resident had taken measures to try and prevent further flooding after 2009 but these were insufficient. PAGE 5 Flood water inside Ash Tree Cottage Following the second flood incident we were asked to investigate the cause of flood and potential mitigation. Working in collaboration with Essex highways and surveying the area key features were identified; such as ditches, surface water pipes and gulleys. This allowed for flow paths to be highlighted and potential sources of surface water so that the problem could be pin-pointed and solutions recommended. The exercise also helped plot highway drainage in that area for the first time to inform maintenance schedules and reduce the risk of local property and highway flooding. Foot path and garden flooded at Ash Tree Cottage Map of watercourse and drainage around Ash Tree Cottage 5

6 SUDS By Kathryn Goodyear We are still working towards an implementation date of April 2014 for Schedule 3 of the Flood and Water Management Act which will make Essex County Council the SuDS Approving Body (SAB). Defra have significantly recruited and held a workshop earlier in the year to set up Task and Finish Groups, which we contribute to, to resolve the issues highlighted in the National Standards consultation which closed last year. We have been continuing to comment informally (the Environment Agency being the statutory consultee for surface water) on SuDS for sites over 1ha through the planning application process and have just reached our 112 th application. The purpose of this is to build capacity for the future role of SuDS Approval Body (SAB) and to advise on the acceptability of SuDS within or alongside roads which are proposed for Essex County Council adoption (which is possible in the interim under S.38 of the Highways Act). We will be contacting planning administration teams shortly to reiterate our criteria for when we would and would not comment as we are currently not receiving applications from all Districts/Boroughs. We are carrying out an on-going SAB trial with Anglian Water and the Environment Agency to reveal how aspects of consultations and determination of SuDS applications will work, as well as how we can record and process them internally. We have also established a SAB Implementation Working Group to work towards an Action Plan to address different aspects of how the SAB will function. The group consists of members from each of the Local Planning Authorities, water companies, Environment Agency and Essex Highways to ensure everyone s interests are captured. The first topic for discussion began in early July and this work is expected to be on going until SAB implementation in April SuDS ponds at Augustenborg in Malmo an integral features of the courtyards SuDS infiltration basins have been integrated with highways at Ravenswood Ipswich. This Scheme is estimated to have saved over 600,000 in the long term (Ipswich Borough Council, 2011) Pervious pavement allowing water to infiltrate through into underlay allowing for temporary storage, at technique used at Sandon Park and Ride 6

7 Who to Contact about Flooding in Your Area Flooding from surface water (rainfall) In an Emergency call 999 During flooding from surface water, groundwater or an ordinary watercourse (open ditches, culverts and drains) contact local District, Borough or Unitary Authority for advice. For property damage by surface water flooding, Essex County Council s Flood and Water Management Team can investigate the cause of flooding and where possible recommend solutions. Tel: flood.prevention@essex.gov.uk. More information: SEPTEMBER 2013 PAGE 7 Upcoming Events Partnership meetings S M T W T F S DECEMBER 2013 S M T W T F S Flooding from rivers and the sea The Environment Agency is responsible for dealing with coastal and main river flooding. Incident Hotline: Recorded flood warning information and advice: More information: Flooding from water pipes Water companies are responsible to dealing with damaged pipes. Anglian Water covers most of the county with Thames water covering Epping Forest, Harlow and parts of Uttlesford Anglian Water: Thames Water: MARCH 2014 S M T W T F S Flooding from highway drains or gullies Essex county council local area highways office Tel: