top of page

Gemini Springs BMAP, 2024 update

When DEP released its updates to Springs BMAPs in 2024, the Florida Springs Council dug into the updated data to answer three questions:

1. Where is the nitrogen pollution coming from for this springshed?

2. What is the difference in pollution levels in this springshed since the 2018 BMAPs were adopted?

3. How is it going? That is, has this BMAP been successful so far, and where has the 2018 BMAP put this springshed on its path to restoration?


Sources of Nitrogen Pollution in Gemini Springs

The largest share of nitrogen loading to Gemini comes from dealing with human waste. 63% of this springshed's nitrogen pollution comes from septic tanks. Turfgrass fertilizer is also notable, at over 30% of the total nitrogen input for Gemini.

OSTDS = Onsite Sewage Treatment and Disposal Systems - septic tanks

WWTF = Wastewater Treatment Facilities

Atmo. Dep. = Atmospheric Deposition. This comes from the air or rainfall and is not a source that can be reduced.

Agricultural sources (livestock, dairies, farm fertilizers, nurseries) are in shades of green.

Development/urban sources (urban and sports fertilizers wastewater and septics) are in shades of yellow and orange.


The difference in pollution levels and required nitrogen reduction in Gemini Springs since the 2018 BMAPs were adopted

Pounds per year of nitrogen at the spring vents - data are based on DEP's actual measurements.


How is it going?

Rather than decreasing, nitrogen levels have increased at Gemini Springs.

The first black dot at 2018 is based on actual data, how much pollution was measured at the spring vent when the 2018 BMAP went into effect.

The next two dots show how things are going right now.

  • The white dot at 2023 shows where the 2018 BMAP should have gotten us. The white line shows the pollution level goals established by the 2018 BMAP, with reductions in nitrogen levels over the next 20 years to reach water quality goals in 2038.

  • The second black dot shows where pollution levels actually are. For Gemini Springs, total pounds of nitrogen measured at the spring vent has increased.

The new goal for 2028 is to get us back to where we started in 2018. Rather than the under 10,000 pounds that was the goal in the previous BMAP, the new goal is to get pollution levels back to the roughly 20,000 pounds we were seeing in 2018 when the BMAP went into effect.

TMDL = Total Maximum Daily Load. That is the water water quality goal - the level of nitrogen coming from the spring vent at which the spring system will no longer experience ecological harm.

Why is the TMDL, or water quality goal, set higher for 2024? Increased rainfall/increased flow since the 2018 BMAPs means that more total pounds of nitrogen can be measured at the spring vent while the overall concentration in the water remains the same.


For a deeper understanding, watch Executive Director Ryan Smart explain this analysis in a one-hour "Springs BMAPs - Live Discussion" video, found at

Questions about these graphs and the Springs BMAP update process? Email 


bottom of page