The Kansas City area has a ton of great trails for running, hiking and biking. There is a lot of variety if you get out and explore a little, some are more hidden than others. It's great to have options in all sections of Kansas City since we are such a spread out area. But apparently trails don't build or maintain themselves. There is a lot that goes into planning, building and maintaining the area trails all done by volunteers.
The Urban Trail Co was created to help build funding for trail building, maintenance and to promote healthy use of the trail systems. Their twitter feed is a great go to source to check if a trail is open or closed. Traffic on muddy trails in the area can cause damage and a lot more work to maintain. It's always good to check before you go since in years like this they can be closed quite frequently.