National Wildlife Refuge System

Scenic view of Chassahowitzka Scenic view of Chassahowitzka Scenic view of Chassahowitzka Scenic view of Chassahowitzka

Chassahowitzka National Wildlife Refuge


About Chassahowitzka National Wildlife Refuge


Chassahowitzka NWR
Chassahowitzka National Wildlife Refuge

Chassahowitzka National Wildlife Refuge (NWR) was established in 1941 to provide habitat for migratory waterfowl and other birds. It provides a habitat and protection for threatened and endangered species such as manatees, sea turtles, and whooping cranes. The 31,000 acre refuge is located along the coast of the Gulf of Mexico just north of Tampa, Florida, as shown in green in the map to the right.


Refuge Area and Class I Designation

  • In 1976, Congress designated 23,578 acres of Chassahowitzka National Wildlife Refuge as a wilderness area, declaring that the area should remain undeveloped and "unimpaired" for future generations.
  • In 1977, Congress acknowledged the uniqueness of the Chassahowitzka Wilderness Area by designating it as a Class I air quality area. As a wilderness area it is afforded special protection under the Clean Air Act.
  • Congress gave the U.S. Fish and Wildlife Service (FWS), as the Federal Land Manager (FLM) of the Chassahowitzka Wilderness Area, the responsibility to protect the air quality and natural resources from man-made air pollution. Despite this protection, many sources of man-made air pollution affect Chassahowitzka, including power plants, phosphate fertilizer production facilities, cement kilns, other industry, automobiles, and other mobile sources.
  • The FWS Air Quality Branch actively participates in the review of permits for new or modified air pollution sources, and has been successful in obtaining emissions reductions from many facilities. However, because of continued and sustained growth in the area, the maximum allowable increase (known as "increment" as mandated by the Clean Air Act) of sulfur dioxide may be exceeded at Chassahowitzka.
  • The FWS and the Florida Department of Environmental Protection (FDEP) are cooperatively studying the incremental status using computer models. If the increment is shown to be exceeded, FDEP will evaluate what remedial action can be taken to address the problem. This includes requiring additional pollution reductions at certain facilities.
  • If the Chassahowitzka Wilderness Area is not protected, unique wildlife and scenic values could be threatened or lost. The FWS hopes to preserve and protect this special area of wilderness for future generations.


Learn more about the air quality at the Chassahowitzka Wilderness Area


FWS monitors air quality at Chassahowitzka in partnership with three national programs: atmospheric pollutants found in rain are analyzed as part of the National Atmospheric Deposition Program (NADP - the "acid rain" program); mercury in rain is analyzed as part of the Mercury Deposition Network Program; fine particles responsible for visibility impairment are measured as part of the Interagency Monitoring of Protected Visual Environments (IMPROVE) program. An automatic camera records visibility conditions.

Monitoring has documented visibility impairment ("haze") at Chassahowitzka NWR. As is found in much of the eastern U.S., visual range in Chassahowitzka is approximately one-fifth of what it would be in the absence of human-caused air pollution. Most people are accustomed to this "haze" and consider it to be a natural effect of humidity. Although humidity exacerbates haze, humidity by itself does not cause haze. Sulfates from sulfur dioxide emissions, nitrates (from nitrogen oxides), and particulate matter all contribute to the haze.

Potential effects of air pollution include vegetation injury and water quality degradation. Several plant species in Chassahowitzka are known to be sensitive to ozone pollution. Field surveys are needed to verify effects to vegetation. Within this web site are the resources to discover why air pollution poses a threat to Chassahowitzka NWR and what the FWS is doing to prevent the deterioration of this pristine area:

  • Learn the basics of air quality - Air Quality
  • Understand what are the air quality related values - AQRV
  • Learn about how air quality can affect natural and scenic resources - Impacts
  • Find real time monitoring data and studies being performed at the refuge - Studies & Monitoring



Additional Information:
Regional Air Quality Information (as provided by NPS)
Chassahowitzka NWR Website
Chassahowitzka NWR 300km Radius Map (PDF 467KB)

Last updated: November 13, 2012