Kansas Geological Survey is a wealth of data and information about water in Kansas. Of particular note is the Geohydrogeology Section found under the first link on their webpage called simply "Water".
Need information about bedrock depths, or saturated thickness, or water levels? These pages have it. Need information about the Ogallala? The KGS has an entire atlas dedicated to the High Plains Aquifer - with maps, graphs and links galore. I find myself referring questions I get to these pages many times. This site is also my starting point for most research I do regarding groundwater.
KGS also interfaces with the Division of Water Resources Water Rights Information System (WRIS) and offers the Water Information Management and Analysis System (WIMAS). This daily updated data base contains all the public information on every water right in Kansas.
Most of the KGS offerings are utilitarian as well - providing searching, sorting, mapping, statistical and analytical capabilities. These pages are well worth the time to get familiar with if you need Kansas water or water rights data.