[skj]

The pressure in the pipe is the same as the pressure in the pool. Additionally, the meter^3/minute is the same in the pool in the pipe, but the with the pipe, the meter^2 is much smaller. So, to keep the same rate of fluid, the meter/minute (speed) has to be much higher.

[billly]

http://en.wikipedia.org/wiki/Bernoulli's_principle Where velocity increases, pressure decreases.