Drove up to Blackwool for a look when I was in the area, I wasn’t that impressed, seemed a bit untidy, messy like. No one was around to have a chat with either.
I'll suggest another place then Snag, and I'll promise it will be better than Chalk Springs!
You wont find the same number of monsters in here though, but there are a sprinkling of doubles, peace and quiet, secluded, mid week you can sometimes get the place to yourself, nice stocking of rainbows and some lovely all wild browns, nice bailiff, lovely "old gentleman’s style" lodge, cheap, and its not too big to be daunting either.
So have a look here
http://www.hastingsflyfishers.co.uk/index.html
If you Google earth the location, you will see that it’s in the middle of nowhere! And I recommend a boat to make the most of it. Only issue, if the wife comes, she will be bored stiff, unless she fishes of course!
Just a suggestion for your birthday, and you may well have fished it already!!