Simplify the following text for a Grade 8 native English-speaking person.
Original: In 2001 â `` 2002 , 52 % of the Murray and Murrumbidgee water runoff was diverted , 77 % of which was used for irrigation .
Simplified: In 2001 â `` 2002 , 52 % of the Murray and Murrumbidgee water was taken , with 77 % of that water used for irrigation .