December brought average rainfall to the region with most of the activity occurring along the central coastline.
A full report outlining December’s hydrologic conditions was presented at the District’s Governing Board meeting Tuesday. Highlights include:
Rainfall
- Districtwide, December rainfall averaged 2.54 inches, which is average for the month.
- The county with the highest rainfall total was Brevard, which received 4.7” rain.
- The county with the least rainfall in December was Indian River, which received only 0.88”.
- Districtwide, the cumulative rainfall total for the past 12 months is 51.91 inches, which is 0.90 inches above the long-term average.
Groundwater
- Upper Floridan aquifer conditions (groundwater levels) at the end of December were in the high range across most of the District with the exception of St. Johns and Volusia counties and portions of Duval, Orange and Lake, which all fell within the normal range. Water levels in many of the wells used for this report remained consistent with November’s levels.
- 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 Jan. 1, flow in most stations across the District was in the average range. The exception was the Econlockhatchee River at Chuluota station and the St. Johns River near DeLand, which exhibited high flow on Jan. 1.
- On Jan. 1, flow in the St. Johns River’s headwaters at the Melbourne station was 231 million gallons per day (mgd) (59th percentile).
- Flow in the Econlockhatchee River near Chuluota was in the high range at 176 mgd (87th percentile).
- Flow in the Wekiva River near Sanford was in the average range at 142 mgd (30th percentile).
- Flow at the St. Johns River DeLand station was in the high range at 2,864 mgd (84th percentile).
- Flow in the Ocklawaha River, the largest tributary to the St. Johns River, was in the average range at 590 mgd (58th percentile).
- Flow at the St. Johns River near Satsuma station was in the average range at 2,902 mgd (42nd percentile).
- Flow in the St. Marys River near Macclenny was in the average range at 246 mgd (70th percentile).
Lake levels
- Lake Brooklyn water levels decreased 0.1 foot to 100.7 feet in December.
- Lake Weir water levels did not change last month.
- Lake Apopka water levels also did not change in December. Lake Apopka is part of a system with water control structures that are operated by the District.
- Blue Cypress Lake levels decreased to 22.7 feet. 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 decreased to 758 cubic feet per second (cfs), or 490 mgd, which is a 31 cfs decrease from November’s mean.
- At the Blue Spring station in Volusia County, the mean monthly flow was 146 cfs, or 94 mgd.
- At Rock Springs, the monthly mean flow decreased 1 cfs to 62 cfs (40 mgd), which is in the high range for December.
- Mean monthly flow at Wekiwa Springs decreased slightly to 64 cfs (41 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.
