I'll ignore the tongue in cheek bit, because you were born and bred in Four Oaks but now live in Redditch, so to a slightly less extent it's the same thing. (Tounge in cheek). But yes to a great extent it does come down to immigration. You can't have a huge increase in the population in a short period of time and not notice the effects. The pollution of our rivers is in a large part down to run off from farms from fertilizer and slurry, waste water and sewage from water companies. The farmers are trying to feed a growing population and the water companies are trying to deal with the end product of a growing population . Yes they care more about their shareholders and profits, than the supply of water and repairing infrastructure.
Everything you mentioned has increased stress put upon it when the population increases. It's a numbers thing. Have the government been slow to react, yes of course they have. As you rightly say with regards to the water companies, dereliction of duty,presided over by the government. But I think I'm correct in saying that Thatcher privatized both water and railways, followed by three terms of a Labour government who did absolutely nothing to reverse those very recently privatized companies despite a lot of hot air from Blair in the run up to the first of his terms in office.
Have the Tories allowed big business to "get away with it" absolutely they have. But to come back to the original point, mass immigration, has societal effects, and if you are going to allow it , then you have to build the infrastructure, housing, schools, hospitals, sewage and water supply etc to cope.
This country needs immigration, but it needs to be managed, not a free for all.