OFW0019452 - complaint against Southern Water

Centre City Tower, 7 Hill Street, Birmingham B5 4UA

21 Bloomsbury Street, London WC1B 3HF

Our Ref: OFW0019452

15 November 2018

Your complaint against Southern Water

Thank you for your letter of 15 October 2018. I am sorry to read that you disagree

with our decision not to open a case in respect of your complaint against Southern

Water Services Limited (Southern Water). I have reviewed your complaint and set

out our position below.

Our review: appeal against our decision not to open a case

We understand that you have asked us to review our decision as you do not feel that

we have considered certain points. We set out in the table below the specific points

raised in your letter and our response to these concerns.

Points raised

Ofwat’s response

Albert Road is one of the only

roads in Deal that

consistently floods whenever

there is heavy rain or

Southern Water’s assets fail.

Southern Water has demonstrated to Ofwat that its

network is resilient to a 1:50 year storm event. This is in

excess of the current standard which is a 1:30 year

resilience. As outlined in the WATRS determination (made

in relation to your complaint), the January 2016 sewer

flooding affected 4 properties internally and occurred as a

result of the sewerage network reaching maximum

You consider that the

capacity during an extreme weather event. It has been

reviewer failed to address the

demonstrated that this was a 1:12 year event and could

reason for the flooding event

not be recreated as the system has already been

in January 2016.

upgraded to a 1:50 year resilience. In light of this, we

consider that we do not need to investigate the January

2016 flooding incident further.

When there is a flooding

As the sewerage system is now resilient to a 1:50 year

event, sewage discharges

weather event, it is unlikely that this will be an ongoing

from the manhole covers that

issue.

get blown off in Albert Road.

The affected part of Albert

Road is the point at which

numerous combined sewers

feed into and that there is

one 825mm sewer serving

that part of Albert Road.

Southern Water has inspected the sewers and fitted flow

meters at various points in the network to identify flow

rates. There has been no evidence to suggest that the

825mm pipe does not have sufficient capacity.

That Southern Water would

not consider bolting down

manhole covers as this may

push the problem further

downstream.

Southern Water has advised that bolting down manhole

covers creates a risk of the network becoming

surcharged. It has also explained (in its letter to you of 9

July 2018) that it has invested heavily in the resilience of

the network and assets as a more appropriate action.

You requested that Ofwat

review the hydraulic

modelling provided by

Southern Water.

One of our engineers with significant experience in

hydraulic modelling has reviewed Southern Water’s model

and we consider that there is nothing in the model or the

results it produces which requires us to investigate further.

We have also sought (and been provided with) further

assurance from Southern Water that flood resilience of

Albert Road will not be affected by the connection of the

new housing estate higher up in the network.

Conclusion

As I explained in my letter to you 8 June 2018 Ofwat is a statutory body and our

jurisdiction is set out in the Water Industry Act 1991 (WIA91). Ofwat’s approach to

enforcement action in respect of sewer flooding complaints outlines our role in

respect of section 94 of the WIA91. Our approach has to be reasonable and

proportionate. We cannot hold sewerage companies to account for flooding which occurs

due to factors outside of its control such as severe weather conditions, for example.

In our preliminary assessment we asked Southern Water to confirm what contact it

had received from residents of Albert Road since January 2016 and more specifically

enquiries relating to sewer flooding. Southern Water provided records which

confirmed that there have been no reports of internal or external flooding from this

particular area since January 2016. Further, Southern Water has invested in

sewerage assets in and around Albert Road in order to alleviate incidents of flooding.

We understand that the upgrades done by Southern Water provide resilience to a

1:50 year weather event. From the information available, I have not seen any

evidence to suggest that Southern Water is in breach of section 94 WIA91.

I hope that you agree that we have given your complaint our full consideration and

although I sympathise with your situation my decision not to open a case remains

unchanged.

Yours sincerely,