If there is a problem with the supply ring 0800 316 9800.
More information from the Thames Water website.
If there is a problem with the supply ring the new national power emergency number 105 which should connect you to SSEN if you phone from a landline or mobile phone within the area.
Alternatively, if the 105 number has connected you to the wrong supplier (very likely from a mobile) you can call SSEN direct on 0800 072 7282.
For a list of General and Emergency Contact Details for Sevenhampton Parish click here.