Question
I am planning to use lake water to use in a lawn sprinkling system.  Where the pump will be located is about 3 feet above the lake water line.

The furthest sprinkler head will be 200 feet away but is approximately 50 feet above the pump.  There is 230 volts available at the pumping staton.  

What size pump will I need to lift the water out of the lake and push it uphill to the furthest spray head.

Answer
A lot depends on the amount of water that will be required by each irrigation zone.  If you have only a small amout of water going out, then you can get by with a smaller pump.  But if your system is going to have a lot of output, you will need to have a larger one.  I would not go less than 1.5 HP for your purpose.  But if you get too large a pump, it can be damaged if the output is too small.