New report sounds alarm on SW Florida water quality. Manatee County has the worst outlook

Booming population growth. Rapidly accelerating development. Way too much fecal matter.

Those are just a few of the major threats to Southwest Florida’s water quality that are underscored in a new analysis from environmental group Calusa Waterkeeper.

All of those sources of pollution and more can be found in Manatee County, which topped a nine-county list for worst overall water quality outlook in the non-profit’s study released last month.

The report used data collected by the Florida Department of Environmental Protection between 2018 and 2020 to gauge factors that impact water quality in nine counties in the Southwest Florida region. It tracked increases in the number of contaminated water bodies as well as pollutants like metals, fecal matter and excess nutrients.

It also measured contributing factors to pollution over time such as population growth, agriculture and new development. The counties were then ranked based on trends towards poorer water quality.

Of all nine counties, Manatee County stacked up the highest threat-level to water quality.

“Manatee County had a combination of impairment sources, with significant influence by both agriculture and urban development which contributed to its first-place rank in overall impairment status,” the report states.

In the development category, Manatee County saw the biggest increases in developed area and impervious area (human-made surfaces that contribute to stormwater runoff) of any county between 2001 and 2016. Manatee also ranked third for land area dedicated to agriculture, which the report notes “is often the dominant source of nutrient pollution in many areas and to downstream counties.”

Other factors contributing to the worsening water quality outlook for Manatee County included increases in fecal bacteria and nutrient pollution in area waterways, as well as accelerated population growth.

In the study, the three counties with the highest population growth (Lee, Collier and Manatee) also saw the highest net increase in impaired water bodies.

And, as the report only tracked instances of water quality impairment currently verified by the state, Calusa Waterkeeper notes that it may just be “the tip of the iceberg” in regard to the true status of Southwest Florida’s water quality.

The study’s county-by-county breakdown was designed to be useful, the author notes, because it often falls to local government to implement water quality restoration efforts.

“Understanding factors contributing to water quality impairment in Florida is important for determining sources and eventual restoration planning,” said ecologist and Calusa Waterkeeper John Cassani, the primary author of the report.

Some other key takeaways from the report:

• About 36% of Manatee County water bodies had some level of documented impairment as of 2020.

• There was an 11% increase in impairments to Manatee County water bodies during the three-year window of the study.

• Of the nine counties, Manatee ranked: First for overall trend toward water quality impairment; first for increased development; first for increased impervious cover; second for percent population increase; and sixth for overall number of impairments to water bodies.

The entire report is available to read at calusawaterkeeper.org/swfl-water-quality-report.

This story was originally published April 2, 2021 at 5:00 AM.