Butterflies of Warren County
- Presents photos and species accounts of butterflies found within the county.
- http://www.butterfliesandmoths.org/map?dc=407&_dcc=1&si=36

Warren County Environmental Data
- Index to program areas, educational information, newsletters and events available through Ohio State University Extension.
- http://warren.osu.edu/

Warren County Solid Waste Management District
- Implements and administers solid waste and recycling programs for residents and businesses in the county. Includes list of recycling centers.
- http://www.co.warren.oh.us/solidwaste/

Warren Soil and Water Conservation District
- Agency responsible for the protection of natural resources within the county that assists landowners in planning and applying conservation practices on their land.
- http://www.warrenswcd.com/

Warren County Ground-Water Resources
- Factsheet providing information on ground-water resources in the county.
- http://ohioline.osu.edu/aex-fact/0490_83.html

Water Resources of Warren County
- Factsheet providing information on water resources and drinking-water quality in the county.
- http://ohioline.osu.edu/aex-fact/0480_83.html