Ive been up a few times as a none member, I tend to go early sunday morning. There is usually a chap ther who opens up, as generally on alternative weekends they have yatchs then ic next weekend, but dont start till 10.00. I always ask if its ok, and am always made to feel welcome, but always leave before 9.45am. In summer I also did the odd sat morning, or if off work the lake is free every weekday.
If going early, I would not use ic, as the lake is very close to residential area, and is bordered one side by trees, so the noise can be a bit loud in the direction of the houses, so it might not be very welcome early sunday!
I live local to this lake, and will make no apologies for the warning, there are a lot of kids about when sometimes they should be at school, try not to go alone if at evening or saturdays, and dont leave ANYTHING unattended, one gate in, one gate out, and before sailing if its something fast, have a look at the lake fro any debris that might have been thrown in! Take old boots, loads of duck crap around the side, but no duck problem if sailing!
.Saying all that, its a fantastic boating lake, very big, rectangular, accessible with waders if required so not too deep, short walk from car even if car park is locked, Access all around, no reeds or trees, and quite sheltered