We are doing a renovation on a hospital in Las Vegas NV. The hospital has two very small patches of landscape that use what we believe to be an efficient irrigation system. To fill out the form on LEEDonline.com, we need to fill in an 'irrigation baseline case' and an 'irrigation design case'. I've been told to fill out what exists at the hospital for the design case, and what "conventional practice" for the area is in the baseline case. How do I figure out what the exact numbers would be for 'conventional practice'?