The Southwest Florida Water Management District is proposing new minimum levels for Pierce Lake, and held a meeting in Land O’ Lakes recently to explain the changes and accept public comment.
Minimum levels are established to protect lakes and wetlands, according to district experts. The minimum level is the limit at which further water withdrawals will cause significant harm to the water resources, and/or the environment.
Pierce Lake is southwest of the intersection, between State Road 52 and U.S. 41. It lies within the Gowers Corner Slough basin.
Pierce Lake has no significant inflow other than overland flow, and at stages above 72.6 feet, it discharges through a ditch at its southern end across a field, according to materials prepared by the water management district.
Both outflows enter the same wetland to the lake’s southwest, the technical report says. It also notes that the topography is flat, and flows are often negligible.
Pierce Lake was selected for reevaluation based on development of modeling tools used to simulate nature water level fluctuations in lake basins that were not available when the current minimum lake levels for the lake were developed, the report adds.
“The review process does take a very holistic look the way this lake’s levels interact with all various different uses and indicators,” Joel Brown, government affairs manager for the water management district, told those gathered.
Such factors taken into consideration include acreage, species in or around the lake, recreational activities and water quality.
Minimum and guidance levels for Pierce were first approved in November 2006 and later implemented in 2008.
These levels are categorized into four parts, each providing a guideline for what healthy water elevation should look like for any given lake.
Environmental scientist David Carr and hydrogeologist Cortney Cameron provided a presentation, detailing how Pierce Lake’s lake levels have varied since 1981.
Cameron, who has studied the lake site for reevaluation, explained how Pierce Lake’s level has varied over decades, plus what it would look like without regional ground pumping.
“Pierce can fluctuate quite a bit,” she said, during her presentation. “Our records show that it’s fluctuated 8 feet in about two years.”
This two-year window occurred from 1998, when records showed elevation at its highest, to 2000, when it was at its lowest. Since then, levels have not varied significantly.
The North Pasco well field was Pierce’s closest water source until it was discontinued earlier this year. The nearest well field is now at Cross Bar Ranch, running at 12,500 acres in North-Central Pasco.
From 1981 to 2003, it was steadily pumping about 25 million gallons of water a day. In the past 15 years, it has cut down to 12 million gallons.
Studies show the correlation between a decline in pumping and the gradual rise of Pierce Lake’s elevation.
Attendees at the workshop did not express major concerns.
The scientists also noted that the elevation growth has not been substantial.
“It’s not the highest it’s ever been and not the highest it’s ever going to be,” Carr said.
The proposed level guidelines for Pierce are not substantially different from the ones adopted in 2008.
The recommended high guidance level is 72.7 feet, which is the same as the previously adopted level.
The recommended high minimum lake level is 71.9 feet, which is slightly less than the previously adopted level of 72.2 feet.
The recommended minimum lake level is 69.8 feet, which is slightly less than the previously adopted level of 70.5 feet.
The recommended low guidance level is 68.5 feet, which is slightly less than the previously adopted 68.9 feet.
The water management district’s governing board is set to make its ruling in November.
A draft report for Pierce Lake’s minimum levels can be found at WaterMatters.org/mflreports.
For additional information, contact David Carr at (800) 423-1476, ext. 4246, or at .
Published October 10, 2018
