I think that this might be some useful context.

https://www.theguardian.com/business/2023/jun/30/in-charts-h...

Overall the debt held by the company has ballooned since the 90s, meanwhile large dividend payments went out to shareholders. This appears to be extraction of value out of Thames Water (TW).

It's hard to see those graphs and then take TW seriously when they complain they need money for investment.