To add to the excellent advice already given


You seem fluent in a lot of the database terminology yet scrambled on the
underlying data organization.

I'd start by shutting off the computer an listing the entities that you want
to track, and the attributes of those entities that you want to record.

Certainly your hydrants are an entity that you are tracking. Locations
might be entities (especially if the same location has many hydrants) or they
might be just attributes of the hydrants.

Any type of attribute where you have that "answer" for nearly every record
(e.g. County) should probably be a field for that record. Where such is
not the case (e.g. stream crossing) such should probably be stuffed into a
more general type field.

Then design your table structure. Don't even think about that other
database stuff (checkboxes, concentating, combo boxes etc. ) until you've
finished that.