High river levels test flood preparedness

In the first week of February we’ve experienced the worst flooding in Oxford since 2014. The coordinated response from the Environment Agency and local authorities shows how far we’ve come in recent years in the management of flood events. We owe them a big thank you.

Back in the early 2000s flood management was reactive and often disorganised. But lessons were learned and we now benefit from much better levels of preparedness, and good cooperation between the various agencies. We also benefit from the infrastructure put in place to divert water away from houses, and from regular clearing of water courses of fallen trees and flood debris.

Bulstake Close barrier and pump

The high level of flooding this year has provided a robust test of flood management procedures. With UK winters getting wetter and wetter we can expect more of these type of events and bigger ones, so it’s important we continue to refine the response to make it as good as we can get it. This is something OFA is actively working on. The flood alleviation scheme is still some years away.

A major weak spot currently is the slow response of Thames Water to residents experiencing sewage leaks. We have had reports of sewers in various locations overflowing as a result of the high flood water. Householders reporting these problems have found Thames Water difficult to engage. OFA is raising these issues with the various bodies responsible for flood management. Oxfordshire MP Robert Courts has insisted Thames Water ‘must do more’ according to a BBC report. We agree.

Flooding from sewer South Hinksey

We also think communication to local residents during a flood event about what’s happening and what’s being done in response could be improved. These events are also an opportunity to educate residents, particularly new residents, about the nature of the flood risk in their area. OFA has initiated discussions about this with the Environment Agency and other interested parties.

At a local level the response in some specific communities can be further refined to ensure the most vulnerable households are known about, and receive timely and targeted help. The new barrier in South Hinksey had its first serious test. It did the job required of it but will need some further adjustments if it’s to be effective in a larger flood. The Environment Agency is looking at this.

We continue to be concerned about safety issues at the Seacourt Park and Ride extension once it is open. We believe there is a significant risk of cars being stranded in flood water there. The Seacourt Stream overflowed into part of the existing car park during the recent foods, leaving parked cars standing in shallow water. The bike rack by the bus stop was also flooded.

Cars standing in flood water at Seacourt P&R

Adrian Porter, from the OFA Steering Group, was interviewed on BBC Oxford on 5 February about the flooding across Oxford and about our ongoing campaigns.

Sewer flooding in South Hinksey

It is not uncommon for residents of Kennington, North Hinksey and South Hinksey to suffer from sewer flooding problems and these continued over the Christmas period with surcharges occurring on both the 24th and 27th December. Both dates coincided with the heavy rainfall events and result from Littlemore Pumping Station being unable to cope with the high volume of water.

The second surcharge was particularly challenging for South Hinksey residents as the EA flood barrier prevented the sewage from leaving the village. Thankfully the pumps the EA had already provided prevented houses from being flooded, but they couldn’t stop a pollution incident as the sewage discharged into the local water courses.

Several residents reported the incident to Thames Water, but their response time was well short of their two-hour target. We know of one call which was responded to eleven hours after being reported, and another which took a whole three days. We’d be interested in other readers’ experiences.

OFA Steering Group member Adrian Porter has once again raised the poor level of service with the Thames Water customer liaison team.

What you should NOT put into the drains or down the loo

 

Fat poured down drains causes fatbergs, solid blockages in the sewers.

Many other things are put down the drains which shouldn’t be and again cause blockages with potential sewer overflow. Such things include wet wipes, tampons, nappies, tights and cotton buds  – none of these should be flushed down the loo, they should go into a bathroom bin.

There’s a pdf leaflet with more detail (but alternate pages are upside down as it’s designed to be printed into a foldable leaflet).

South Hinksey sewer flooding

We held a meeting on 20 August 2015 to discuss this, especially in relation to possible temporary bunding of the village at time of river flooding.

Representatives from Thames Water (TW), the Environment Agency (EA) and of OFA from South Hinksey met. We had an interesting and fruitful discussion. These actions were agreed:

Thames Water (TW) to initiate a clean of the box culvert north of the village (by today, 27 Aug, this has already been ordered) and update us further on the work that has been, and still is being, done to considerably improve the pumping station at Littlemore.

TW will consider OFA’s suggestion of a sewer bypass for the village, as part of the ongoing Oxford Catchment Study.

Adrian Porter for OFA will fit a chain and handle to the existing non-return flap valve on the Manor Road surface water outlet to enable manual override if necessary.

The suggestion of a memorandum of understanding between the EA and TW, as to how sewer flooding would be dealt with at times of fluvial flooding, especially if a temporary bund were deployed, will be taken forward by the EA.

Many thanks to Thames Water and the Environment Agency for meeting with us and their very positive approach to the problems.

Working to reduce sewer flooding

Simon Collings represented OFA at the second meeting of Oxford City Council Scrutiny Panel on sewer flooding. Thames Water (TW) gave an update on where they are with a) Grandpont and b) the Oxford Catchment Study:

At Grandpont they have identified the most likely causes of sewer flooding and TW will now work with the City Council and residents to improve things. Local resident Brian Durham of OFA and SOFAG has been closely involved in this work.

On the Catchment Study they are engaged in two parallel processes:

  • a physical inspection of assets across the city – with any issues they identify being fixed as they go along (where the business case is obvious). This includes an inspection of both main trunk sewers.
  • customer surveys to help them understand where problems arise during a flood and how these manifest themselves.

So far they haven’t encountered anything which would suggest they need major capital investments, though they do plan to upgrade the pumps at Littlemore.

TW are talking to the Environment Agency (EA) team working on the Oxford Flood Alleviation Scheme, and the two modelling teams are going to share data and work together. By good luck the option development phases of both projects are working to similar timetables. EA will help TW understand how the river flooding affects the sewers, and TW will contribute to that work.

There will be one more meeting of the Scrutiny Panel in November/December but from then on formal reports will be given through the Oxford Area Flood Partnership, to avoid duplication of meetings.

Thames Water sewer flooding surveys under way

Heard from Thames Water today that their Oxford flooding questionnaire team has been out and about making visits and gathering information from householders – by the end of today all Oxford Phase 1 sites should have had at least one visit: three visits will be made in total to try to catch people that are out.  So far, 126 Sewer Flooding Questionnaires have been completed.

Phase 2, to follow, comprises Lower Wolvercote, North Hinksey Lane, South Hinksey and Upper Road.

Great that this is moving ahead – we look forward to hearing the results in due course.

Sewer survey starts soon

Oxford has had serious problems with sewer flooding for years, mainly at times of river flooding. Now Oxford has been chosen by Thames Water as one of only a handful of places in their region to have this investigated in detail, so they can decide how best to go about making real improvements.

Surveys of the sewers themselves have been under way for some time. Now, within the next two or three weeks, representatives from Thames Water will begin to knock on doors in areas of Oxford and environs that have experienced sewer flooding of house or garden, or toilets that will not flush during floods. The more that Thames Water know about the problems the better they will be able to solve them, so we urge everyone to give as much information as they can. This really is a big chance to see things improve.

We will post more details as they become available.

Thames Water’s Oxford (sewer) Catchment Study – meeting

Two of us met with two people from Thames Water today. Thames Water are getting on with the first stages of their Oxford Catchment Study, designed to find out why we get sewer flooding in many parts of Oxford. Some technical studies have already been done, house to house interviews with residents in affected areas will begin quite soon. A dedicated website should be up and running shortly, possibly as early as next week.

We are delighted that this study is happening – Oxford is one of only five places in Thames Water’s area to be having such a detailed study. This is a necessary first stage in, hopefully, getting action to remedy the problems. We are helping in any way we can.

This study will be used, along with other evidence, to guide Thames Water when they consider how much the proposed Oxford Flood Alleviation Scheme would help solve sewer problems – and hence, presumably, how much they could consider contributing to that multi-partner scheme.

Thames Water agree how important it is that when new building is proposed that there is adequate prior consideration given, i.e. at the planning stage, to whether the sewer system will be able to cope.

Sewer survey

Thames Water is asking members of OFA Steering Group and OFA Allies to help in their comprehensive survey of sewers in the Oxford area by being area representatives. Nick Hills, Angela MacKeith, Brian Durham, Adrian Porter, Richard Thurston and John Mastroddi will be involved.

We’ve suggested Thames Water contact OFA Allies in Wolvercote, Wytham and Binsey as well.