I was going to try to have the man-hole covers and you can just uncover one and the hydrant would pop out - I'll try to contact the Berlin team and see if I can get their standpipe script.
Edit:- Their website is down and Woltep hasn't been on since 2011 so it looks like I'll have to make one myself.
I thought it would be quite essential. A tanker will be pretty cool. The script from the Berlin mod sounds awesome, if you could make something similar I would be very impressed!