Summer Rain in the Florida Panhandle
ARTICLE BY DR. MATT DEITCH; water quality specialist – University of Florida Milton
Summer is a great time for weather-watching in the Florida panhandle. Powerful thunderstorms appear out of nowhere, and can pour inches of rain in an area in a single afternoon. Our bridges, bluffs, and coastline allow us to watch them develop from a distance. Yet as they come closer, it is important to recognize the potential danger they pose—lightning from these storms can strike anywhere nearby, and can cause fatality for a person who is struck. Nine people were killed by lightning strike in Florida in 2016 alone, more than in any other state. Because of the risk posed by lightning, my family and I enjoy these storms up-close from indoors.
A fraction of the rain that falls during these storms is delivered to our bays, bayous, and estuaries through a drainage network of creeks and rivers. This streamflow serves several important ecological functions, including preventing vegetation encroachment and maintaining habitat features for fish and amphibians through scouring the streambed. High flows also deposit fine sediment on the floodplain, helping to replenish nutrients to floodplain soil. On average, only about one-third of the water that falls as rain (on average, more than 60 inches per year!) turns into streamflow. The rest may either infiltrate soil and percolate into groundwater; or be consumed and transpired by plants; or evaporate off vegetation, from the soil, or the ground surface before reaching the soil. Evaporation and transpiration play an especially large role in the water cycle during summer: on average, most of the rain that falls in the Panhandle occurs during summer, but most stream discharge occurs during winter.
The water that flows in streams carries with it many substances that accumulate in the landscape. These substances—which include pollutants we commonly think of, such as excessive nutrients comprised of nitrogen and phosphorus, as well as silt, oil, grease, bacteria, and trash—are especially abundant when streamflow is high, typically during and following storm events. Oil, grease, bacteria, and trash are especially common in urban areas. The United States EPA and Florida Department of Environmental Protection have listed parts of the Choctawhatchee, St. Andrew, Perdido, and Pensacola Bays as impaired for nutrients and coliform bacteria. Pollution issues are not exclusive to the Panhandle: some states (such as Maryland and California) have even developed regulatory guidelines in streams (TMDLs) for trash!
Many local and grassroots organizations are taking the lead on efforts to reduce pollution. Some municipalities have recently publicized efforts to enforce laws on picking up pet waste, which is considered a potential source of coliform bacteria in some places. Some conservation groups in the panhandle organize stream debris pick-up days from local streams, and others organize volunteer citizens to monitor water quality in streams and the bays where they discharge. Together, these efforts can help to keep track of pollution levels, demonstrate whether restoration efforts have improved water quality, and maintain healthy beaches and waterways we rely on and value in the Florida Panhandle.