Thread by @cammaynard

Penetrating the Murk – update 🧵 on how Cllrs Arciszewska, Maynard and Smith and WODC officers have been working with @thameswater over the last 12 months to improve our sewage situation.
🧵1/13

TW uses four key inputs to calculate required Sewage Treatment Works (“STWs”) capacity:
2/13

i) Population – after pressure, TW has now stopped using their highly inaccurate forecast data. TW and WODC have worked together to generate a more accurate picture of forecast population.
3/13

ii) Consumption – TW have agreed to accelerate their smart meter roll-out in West Oxfordshire. TW believe this will reduce water use by 12%. Good news. Trust but verify.
4/13

iii) EA’s multiplier – the EA recommends 3.0x. However, TW is using multipliers as low as 2.4x, despite TW’s appalling track record. TW has now agreed to apply 3.0x to all planned works.
5/13

iv) Infiltration - 47% of STW flows are from ground & surface water infiltration. Fixing this is a huge task. We’re working to agree on metrics which will track progress. 6/13

Fixing the above inputs will result in larger capacity increases being factored in when TW upgrade STWs. 7/13

TW has agreed to accelerate its works upgrade plan. More data is now on thameswater.co.uk/edm-map re what works TW is planning where. Some look good. However, some aren’t large enough or lack info. We remain on the case.
8/13

TW will be launching a “fix my sewer” equivalent to “fix my street”. This will cut the hours wasted reporting problems by phone.
9/13

We’ve changed WODC’s planning checklist so it is always clear at the start of a planning application whether the relevant STW has sufficient capacity to accommodate more homes.
10/13

WODC can now add a clause into planning apps requiring TW to increase the capacity of failing STWs prior to the new homes being occupied. Potential buyers will be informed.
11/13

TW has agreed to work on their responses to planning applications. Their response is still too often “no problem” when there are obvious problems that they should be highlighting.
12/13

@WodcNews, @thameswater, @WindrushWasp, @Feargal_Sharkey, @sandralaville, @gillplimmer1, #sewage,
13/13