Subject: RE: River Thaw at Cowbridge NRW:00664552

From: "England, Tim" 

CC: Enquiries 

Thank you for your email dated 19 November 2019 which has been passed on to me.  Unfortunately there has been a delay since receiving the email and it reaching the appropriate person for response.  I am sorry about this, but will look into what has caused the delay to ensure it does not reoccur.

With regard to the questions you ask, please see our response (in blue) below.

• What was the fault?  There was a minor water leak at the flood storage scheme located upstream of the A48.

• Has it been rectified?  We have undertaken an initial repair to the leak (using the clay you refer to), but will require further work to the structure to enhance its day to day operation.

• What caused the surge on 4 November?  Was this man made by NRW?   NRW did release extra water from the storage scheme to facilitate the repair mentioned above and to create some additional storage capacity.  Whilst making the releases, we had staff on site monitoring water levels downstream in both Cowbridge and Llanblethian to ensure the releases we made did not cause flooding.  The rate of release was adjusted accordingly to ensure downstream water levels were managed appropriately.

• What caused the surge on 18 November? Was this a controlled event by NRW?   NRW did release water from the storage scheme to lower water levels ahead of forecast heavy rain.  Again, NRW staff were on site monitoring levels at Cowbridge and Llanblethian to ensure we did not cause flooding.

• If No. 2 is negative, what is being done to ensure non recurrence of these surges which are themselves most disconcerting?  Please refer to points 3 and 4 above.

We are sorry if our actions in lowering water levels upstream have caused you concern, but please be reassured that the actions we have undertaken have been planned and managed accordingly to ensure no detriment has occurred in either Llanblethian or Cowbridge.

Having experienced flooding in 1998, we can fully appreciate your interest and concern regarding the water levels in the watercourses running through Llanblethian.   We are confident that the upstream flood storage scheme has prevented flooding in Cowbridge and Llanblethian on a number of occasions since it’s construction.  The scheme is an important asset but, like all engineered structures, it will require ongoing maintenance and repair, as is happening now, to ensure it remains fit for purpose.

I do hope I have addressed your concerns, but if you require any further information, please do not hesitate to come back to me.

Yours sincerely,

Tim.

Tim England

Rheolwr Gweithrediadau - Rheoli Dŵr a Llifogydd (Y De) / Operations Manager - Flood and Water Management (South)

Cyfoeth Naturiol Cymru / Natural Resources Wales  
Ffôn / Tel: 03000 65 3042
Plas Yr Afon, Caerdydd / Rivers House, Cardiff

www.cyfoethnaturiol.cymru / www.naturalresources.wales 

To check the River Thaw water level each day click on the following link: River Thaw water level  

Yn falch o arwain y ffordd at ddyfodol gwell i Gymru trwy reoli’r amgylchedd ac adnoddau naturiol yn gynaliadwy.

Proud to be leading the way to a better future for Wales by managing the environment and natural resources sustainably.

Croesewir gohebiaeth yn Gymraeg a byddwn yn ymateb yn Gymraeg, heb i hynny arwain at oedi