Rainfall in October slightly below average Districtwide

PALATKA, Fla., Nov. 9, 2021 — While it is still storm season around the St. Johns River Water Management District, October brought rainfall well below the long-term average.

A map illustrates rainfall conditions in October across the St. Johns River Water Management District.

A full report outlining October’s hydrologic conditions was presented at the District’s Governing Board meeting Tuesday. Highlights include:

Rainfall

• Districtwide, October rainfall averaged 2.63 inches, which is 1.38 inches below the long-term average for the month.
• Many counties only received roughly half the normal October rainfall, including Clay, St. Johns, Flagler, Putnam, Brevard and Indian River.
• The County with the highest rainfall totals was Volusia, with 3.3 inches of rain.
• The counties with the least rainfall in October were Clay, with only 1.6”, followed by Putnam and Flagler (1.9”), and St. Johns (2.0”).
• Districtwide, the cumulative rainfall total for the past 12 months is 50.92 inches, which is 0.09 inches below the long-term average.

Groundwater 

• Upper Floridan aquifer conditions (groundwater levels) at the end of October were either in the high or normal range throughout the District. Water levels in many of the wells used for this report decreased more than 10 percentile points during the month.
• Groundwater levels are at the 82nd percentile Districtwide. This means that since 1980, aquifer levels have been higher than they currently are about 18 percent of the time.

Surface water flows

• On Nov. 1, flow in most stations across the District was in the average range. The exception was the St. Johns River at Melbourne station, which had flows in the low range, and the Econlockhatchee River at Chulota station which exhibited high flow on Nov. 1.
• On Nov. 1, flow in the St. Johns River’s headwaters at the Melbourne station was 184 million gallons per day (mgd) (24th percentile).
• Flows in the Econlockhatchee River near Chuluota were in the high range at 278 mgd (86th percentile).
• Flows in the Wekiva River near Sanford were in the average range at 180 mgd (73rd percentile).
• Flows at the DeLand station were in the average range at 3,004 mgd (54th percentile).
• Flows in the Ocklawaha River, the largest tributary to the St. Johns River, were in the average range at 587 mgd (57th percentile).
• Flows at the St. Johns River near Satsuma station were in the average range at 3,845 mgd (38th percentile).
• Flows in the St. Marys River near Macclenny were in the average range at 159 mgd (75th percentile).

Lake levels

• Lake Brooklyn water levels decreased 0.1 foot to 101.0 feet in October.
• Lake Weir decreased by 0.2 foot to 53.6 feet.
• Lake Apopka decreased by 0.1 foot to 65.5 feet.
• Blue Cypress Lake levels increased to 22.7 feet, slightly below the regulation schedule for this time of year. Blue Cypress is also part of a system with water control structures that are operated by the District. During April and May, the regulation schedule levels drop in preparation for the summer wet season.

Spring flows

• The mean monthly flow at Silver Springs increased to 821 cubic feet per second (cfs), or 531 mgd, which is a 18 cfs increase from September’s mean.
• At the Blue Spring station in Volusia County, the mean monthly flow was 150 cfs, or 97 mgd.
• At Rock Springs, the monthly mean flow decreased 1 cfs to 64 cfs (41 mgd), which is in the high range for October.
• Mean monthly flow at Wekiwa Springs decreased slightly to 66 cfs (43 mgd), which is in the normal range for the time of year.

To learn more about rainfall totals and other hydrologic data collected, visit sjrwmd.com.

Visit WaterLessFlorida.com for tips to help landscapes thrive while saving water and money. Watch the weather and wait to water during Florida’s summer rainy season. Follow the water conservation conversation at #sjrwmd #waterconservation #savewater.