FLOOD WARNINGS Oxford Area Flood Partnership
Environment Agency – Floodline Warnings Direct
By phone Register to receive free Flood Warnings by phone, email or fax to landline or mobile numbers for your home and other places. Information for residents, owners and other stakeholders Register online https://www.fws.environment-agency.gov.uk/app/olr/register
Flood Response Plan
Flood warning The three levels of warning are: South Oxford Area Severe Flood Flood Alert Flood Warning Warning Guide No.2 of a series - for Oxford flood risk areas
Summary
Flooding in South Oxford generally develops slowly, giving time to respond.
The Environment Agency (EA) will give the public at least two hours’ notice of Flooding is possible. Flooding is expected. Severe flooding. any local main river overtopping its bank (flood alert) or flooding properties Be prepared Immediate action required Danger to life (flood warning). By monitoring escalating situations, flood response organisa- tions will normally be ready least one day ahead.
Once alerted, City Council staff check critical river levels several times a day in order to track the rate of rise and decide whether and when to deploy tem- LATEST INFORMATION during a flood porary defences. Environment Agency Call ‘Floodline’ (24 hrs) on 0345 988 1188 to hear up-to- date local flood Variations in timing, rate, location and total amount of rainfall make each flood warning and river level information or speak to an operator. different. So, while guided by experience of previous floods, OAFP partners The type talk number for this service is 0845 602 6340. liaise closely in order to focus on making best use of available resources and
‘Live maps’ (updated every 15 mins) enable response to be based on the developing situation. We aim to imple- ment as much as possible during daylight hours. https://flood-warning-information.service.gov.uk/warnings
Under flood response conditions, the Oxford Area Flood Partners increase the Others number of staff on standby and monitor flooding in all critical areas. They stay Listen to Radio Oxford in frequent contact with other organisations working in the area, including the Follow the Oxford Mail Flood blog Emergency Services. Council web pages change to improve links during emergencies: Oxfordshire County Council http://www.oxfordshire.gov.uk As floods develop, incident coordination centres and local communication Oxford City Council http://www.oxford.gov.uk centres are set up which liaise with regional and national centres. This ena- bles a comprehensive and rapid response as appropriate to each situation as Version: Aug 2014 it evolves.
1. (See back page for details of ‘Floodline Warnings Direct’)
Response arrangements IS YOUR PROPERTY AT RISK OF FLOODING?
EA “Flood Alerts” and ‘Flood Warnings’ prompt City Council staff to moni- tor river levels frequently. The EA internet pages. The EA internet pages Flood Risk maps show the developing situation for many of the main rivers in Oxford. https://flood-warning-information.service.gov.uk/long-term-flood-risk
As river level rises, it drives a slow increase in the level of groundwater. 3 day Flood Risk Forecast The effects can be seen in Hinksey Lake, which rises slowly in the early stages of each flood https://flood-warning-information.service.gov.uk/5-day-flood-risk
Vicarage Road: The City Council deploys a pump at the corner and moni- Environment Agency flood information tors the groundwater level at the low point in the road gully there. https://www.gov.uk/browse/environment-countryside/flooding-extreme-weather
Hinksey Park: The Environment Agency monitors progress of the flood across Hinksey Park once Eastwyke Ditch overflows and, at a suitable point, installs the temporary barrier, to protect the Vicarage Lane area. PLAN HOW TO DEFEND YOUR PROPERTY
The barrier comes into use once the water from Eastwyke Ditch reaches Hinksey Lake, which then fills quickly. For advice on household flood defence Vicarage Lane: With the EA barrier in place, the City Council fits a stop- National Flood Forum per to the surface water sewer in Vicarage Road to prevent backflow from http://nationalfloodforum.org.uk/ Abingdon Road. It then pumps leakage from Vicarage Lane, back to the Association of British Insurers – lake. https://www.abi.org.uk/products-and-issues/topics-and-issues/flooding/
Road closure: As floods develop, groundwater rises further, the outfall of
the Abingdon Road surface water becomes less effective and water reaches the Abingdon Road across Cow Mead Allotments (north of Chat- ham Road) by stream overflow through Northampton Road and Wytham Street. Oxfordshire County Council decides a suitable time to close Ab- ingdon Road, as it starts to flood. Only local traffic is then permitted through the barrier at Folly Bridge in order to protect motorist and houses. LEARN FROM OTHERS Temporary toilets: Rising groundwater can leak into the foul sewers and overload them. This prevents ground-floor toilets from working and caus- es sewage overflows from inspection chambers in many gardens. At this Your local flood action group point the City Council provides and services mobile “festival” toilet blocks, Oxford Flood Alliance (OFA) in several locations when needed. (See map) http://www.oxfordfloodalliance.org.uk/
We ask ALL residents in flooded areas to reduce sewer problems, at this South Oxford Flood Action Group (SOFAG) time, by using the mobile toilet blocks when necessary; by not flushing [email protected] any WCs at home unless absolutely necessary; and by minimising other water use, such as washing machines.
REPORT PROBLEMS during a flood Oxford City Council 01865 249811 (switchboard) (or use the report form on the website) www.oxford.gov.uk (put ‘Flood’ in search box) HOW TO USE SANDBAGS EFFECTIVELY ‘Live river levels’ can be checked on the EA website
https://flood-warning-information.service.gov.uk/river-and-sea-levels Sandbags This shows water levels upstream and downstream of most locks. Sandbags can’t stop water: They can only slow it down. A plastic sheet larg- er than the area being covered will be needed to work with the sandbag to This is a typical display. make an effective flood barrier. A single sandbag in a bin bag, stamped against an airbrick, would be more The graphic display updates effective at saving your home from flood than a heap of sandbags. And a every 15 minutes. few, close-packed against sheet of plastic, can protect a doorway. The river level reading is Moving fewer bags might save your back too! updated daily: Click here to see levels up- Sandbags are good for stopping waves from passing traffic, washing (More often during floods). stream of lock into your garden or against your house, but will not hold back standing water. So if your house is at risk, purpose-made barriers (with airbrick protec- tion if appropriate) and a pump would be a worthwhile investment.
The Environment Agency provides advice on using plastic with sandbags, and how to lay sandbags if more than one layer is needed: https://www.gov.uk/government/publications/sandbags-how-to-use-them-to-prepare-for-a-flood
The City Council will establish a temporary distribution point for sandbags on Abingdon Road, the location of which may vary dependent on the areas at risk, and the areas available to set up. Previous locations have included: Redbridge Park & Ride Duke of Monmouth pub Fox Crescent It may also deposit pallets of sandbags at other locations
OXFORD AREA FLOOD PARTNERSHIP
Oxford Area Flood Partnership (OAFP) formed after the 2003 floods, to help local organisations better co-ordinate their flood management activities. The partners are: Oxford City Council The Environment Agency Oxfordshire County Council Thames Water Utilities Vale of White Horse District Council Network Rail
OAFP works closely with interested groups in the community. Details can be found on the Oxford City Council website www.oxford.gov.uk (search: flood)
FIRE & RESCUE SERVICE Managing groundwater Its role in flooding
Groundwater is a particular issue in South Oxford.
Groundwater rises more slowly than the rivers, and in some low spots The Fire & Rescue Service assisted in the floods of February 2014, by can continue to rise as river levels fall, until levels equalise. helping to keep the Botley Road open with its pumps and ensuring that the Abingdon Road could be opened much sooner than otherwise possi- So a persistent river flood might affect a property that would otherwise be ble. unaffected. Despite having no statutory responsibility for responding to flooding, Airbrick protection Oxfordshire County Council’s Fire & Rescue Service (OFRS) is trained In the early stages of a river flood, it can help to leave airbricks open as and equipped to undertake water rescue and pumping activities during an outlet for water because internal flooding by groundwater can be a floods to provide an appropriate emergency response across the county. worse threat to some houses than flooding from outside. Airbricks at the However, flooding can impact in different ways on different occasions and back of the house might be more effective for this if they are the lowest this may result in the Service having to respond to different priorities as a point below floor level. flooding event progresses. Therefore, there can be no guarantee that the
In order to maximise sub-floor ventilation, it’s best to close airbricks as Service will be able to respond in exactly the same way and with the same results as previously. late as possible (with covers or sandbags) and to re-open them at the earliest opportunity. With this in mind, OFRS is keen to support multi-agency prevention work
Automatic airbricks would help, as they act as one-way valves. and community resilience activities, as well as helping to co-ordinate and respond to areas that are in danger of flooding, in order to help miti- Pumps gate the risks and minimise the impact of the floods on residents and
Other than installing solid concrete floors, nothing can be done to stop the businesses. flow from below. It could be worth considering fitting pumps to re- move water faster than it enters, as that could prevent some floods from In Feb2014, as floods started to reaching a floor where damage could occur. The water should be held recede, OFRS used the option to just below floor level, as it’s important not to pump groundwater un- provide long ‘hose barriers’ to pre- necessarily (both because of the cost of electricity to you and the risk of vent continuing flooding of Abing- causing flooding to others through inappropriate discharge). don Road and pumped accumulat- ed floodwater to enable re-opening In South Oxford, most houses have been built high enough with flood of the road sooner than otherwise cellars or basements to allow for most rising groundwater. possible. However, some owners have converted these sub-floor spaces to stor- age or habitable space that can be at particular risk of flooding by groundwater or sewage. Owners need to take special precautions, in- Pumping to Weirs Mill Stream cluding ‘tanking’, if they have such property. TYPES OF FLOODING (continued) TYPES OF FLOODING
Surface Water Flooding Groundwater Flooding
In Oxford, river floods drive groundwater through flood-plain gravels, when Surface water flooding (flash flooding) can occur anywhere during heavy it can come up under floors or affect low-lying areas. Although called rainfall, giving little time to respond. ‘groundwater flooding’, the effects are temporary and recognised locally as an Environment Agency issue, linked to river flooding. Maps on the Environment Agency website show areas at risk.
Elsewhere in the UK, true groundwater flooding can persist for months https://flood-warning-information.service.gov.uk/long-term-flood-risk when driven by large underground water reserves. It is then an issue for Lead Local Flood Authorities. Surface water flooding can also occur when rainfall exceeds the capacity of highway drainage systems or surface water sewers, or these have become blocked.
Blocked drains should be reported for investigation to …
Oxfordshire County Council 0845 310 11 11 or
https://www.oxfordshirefloodtoolkit.com/emergency/report-flood/
Sewer Flooding
Many of Oxford’s foul sewers are connected to rainwater systems and River (fluvial) Flooding can overflow during heavy rainfall in the absence of river flooding. River flooding happens when the channel of a river or stream cannot cope
However, during river floods, higher groundwater levels infiltrate the net- with the volume of water from upstream, typically when heavy rain falls on work and cause sewage overflows and loss of use of WCs. ground that is already waterlogged. Where possible, the river then spreads across its natural floodplain, which in some parts affects urban areas You should report problems to Thames Water on 0800 316 9800 including houses, roads and businesses .
Maps on the GOV.UK website show areas at risk ... https://www.thameswater.co.uk/help-and-advice/drains-and-sewers/sewer- https://www.gov.uk/check-if-youre-at-risk-of-flooding flooding-who-to-contact
It helps if each affected household reports problems, to help Thames Water establish the extent of the problem. Abingdon Road Closed to buses and through traffic- when neces sary to protect housses (Local access traffic only)
WC
Hinksey Park Temporary bbarr ier
Vicarage R oad Temporary ppump
Vicarage R oad Temporary stopp er in surface w ater sewer
Weirs Lan e Closed to a ll traffic
Abingdon Road Closed to a ll traffic when necessary to Reproduced from the Ordnance Survey map with the permission of the Controller of Her protect hou ses Majesty's Stationery Office (HMSO).Crown Copyright. Unauthorised reproduction in- fringes Crown Copyright and may lead to prosecution or civil proceedings.Oxford City