Spitoon, I know that it is the pilot's responsibility (and Rustle, that the buck stops here), but how am I as the pilot supposed to know in this case what is okay? I suppose in some ways the answer is if you can't be sure then you shouldn't do it, but the very first time I got in a plane I wasn't sure I could get it to take off by going to full throttle and pulling back on the stick when I hit 60knts, but the instructor sitting next to me had told me that I can so I did it and he was right, it worked.
Rustle, good point about the police condoning speeding. They have to give you 10% I believe, due to inaccuracies of your speedo (or is this an urban myth). Certainly I'd drive past a police car quite happily at 80 in good weather and light traffic. But then you can go too far with this stuff - could they bust you for saying "three" instead of "tree", despite it being common practise and not generally taken up on?
I looked in the GetMapping book and it does look like there are places either side of the reservoirs which would make suitable landing spots. South of that though the river looks like the only option to me, though it is hard to tell.
Also, unless I've misunderstood, I think AlanM and the guys issue a VFR clearance, not an SVFR one.