If the equipment is going to be based off of the same ceiling level, then you should use the same Reference Plane (or Level) to host them both. As I mentioned previously, Ducts must be associated with a Level, not a Reference Plane.
River Itchen. The River Itchen is a beautiful chalk stream which flows for approximately 28 miles from mid-Hampshire to Southampton.he source of the Itchen is situated in Cheriton, near Alresford, and flows down to the historic city of Winchester passing through nature reserve Winnall Moors, and Winchester City Mill.
Report Abuse. The source of the Mississippi River is Lake Itasca (which is 1,475 ft above sea level) in Itasca State Park located in Clearwater County, Minnesota. It ends in southeast Louisiana. However, through a natural process known as delta switching the end of the Mississippi River has shifted its final course to the mouth of the Gulf of Mexico every thousand years or so.