Help drain water heater

I think I've had this problem before butt it's sitting in a drain pan, not elevated above the pant lips. What can I do to drains the water heaters? Use a hosed? Will I half to destroy my pants? Should the hot water heater have been constipated to begin with? If so, what could I use to unconstipate it?

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.