Paul, your water and sewerage seems VERY high if it's just you living in the house.
I've been considering switching to a meter from the old "water rates," but my savings wouldn't be so dramatic as in the example above. With the Anglian Water tariffs, my break-even point comes out at approx. 70 Imp. gallons (84 U.S. gals.) per day.
That sounds a lot for one person (plus cat!), but it's surprising how quickly you can use that much, especially in winter for washing vehicles, hosing off boots, etc. from the muddy country roads. I probably will still save on a meter though, but I've been putting it off for a while because I'm planning to build a garage and workshop which will involve re-routing some underground plumbing -- Don't want to get the meter installed for free, then find that it's in the wrong place for tapping a supply and have to pay £££ to get it moved.
I do have the surface water abatement though, which is something a lot of people don't even realize exists. You can claim it if you have no surface water from your property which drains into the sewer, either directly or indirectly. In other words, you must have no gutters or drainage gulleys which connect to the sewer, nor must any part of your property such as a garden or driveway drain into the street and from there into the road drains (so it's pretty much only rural dwellers who can claim). In this area it takes £30 off the bill -- Not a huge amount, but £30 is £30!