How can they assume it it Merseyside that is polluting this bay? It mentions tidal, that means seawater from the oceans could be mixing in with the Mersey and causing this. How then can they prove it is the Mersey that is causing the pollution. Sea containers, trawlers and ships from around the world travel through this area, so I think they should investigate if the damage to the ocean comes from these first. We have high enough water bills without the excess added. Britain is an island, surrounded by water.
Considering how much they seem to be spending on this investigation, I'm pretty sure that they'll be taking that into account. What I'd be more interested to know, is whether the nutrification is man made or natural. If it's natural, why should we by trying to change it? If it's not, then why not pass on any fines and costs to the prople that are causing it? At the end of the day, if the water board or private businesses are polluting it and get fined as a result, their profits should bear the cost, not the customers.