Hydrologic data collection program and reports

Controlled water level information for selected areas of the Upper St. Johns River and Upper Ocklawaha River basins is accessible via the links below.

To comply with federal mandates and to ensure consistency with other state and local governments, the district is in the process of converting how it measures and reports elevation data. The former system, known as “mean sea level,” is officially known as the National Geodetic Vertical Datum of 1929 (NGVD 29). The new system is known as the North American Vertical Datum of 1988 (NAVD 88).

About springs discharge data

The St. Johns River Water Management District develops stage discharge ratings for springs from graphical analysis of current-meter discharge measurements from various monitoring stations on vary­ing schedules and made over a range of stages and discharges. Shifts in measure­ments can be short- or long-term and can be caused by changes in the streambed, vegetation growth, backwater conditions and other variables. Archived data pro­vided are shift corrected, incorporating the mathematical adjust­ments for rating. The shift adjust­ments are applied to the individual ratings as measured data be­comes available, resulting in an adjusted rating. Flow data posted as part of the springs stage dis­charges page is provis­ional and subject to change.