2010 Dry Wells, Sinkholes Drive New Water Rules for Freeze Management

Hoping to avoid a repeat of last year’s spread of sinkholes, the Southwest Florida Water Management District (SWFWMD) has issued new rules for existing and future water-use permit holders with crops that require frost and freeze protection.

The Dover/Plant City Freeze Management Plan took effect June 16 for a 256-square-mile "water-use caution area" in Eastern Hillsborough County.

District officials developed the rules in response to the 11-day freeze in January 2010 that resulted in dry wells and sinkholes throughout Eastern Hillsborough.

The 13-member SWFWMD governing board approved the rules at its December meeting; the governor’s office signed off on the rules last month.

Robyn Felix, spokesperson for SWFWMD, said more than 140 skinholes and 750 dry wells occurred in Dover and Plant City during the January 2010 freeze as a result of agricultural pumping to protect crops.

“After that happened," she added, "we said we would go back and look at all our procedures in order to see where we could make changes so this never happens again.”

The review included public workshops and consultation with local government agricultural community representatives.

“These changes are the result of that review,” Felix said.  

The  new rules, as posted on the SWFWMD Website:

• Establish a Minimum Aquifer Level and Minimum Aquifer Level Protection Zone. A minimum aquifer level is the level at which further withdrawals will cause significant harm. The Minimum Aquifer Level Protection Zone is the area where the greatest concentration of withdrawal impacts -- such as well complaints and sinkholes -- have occurred. The proposed minimum aquifer level has been set at 10 feet above sea level at the District’s DV-1 monitor well.
• Require automatic meter-reading devices. Flow meters and automatic meter-reading devices are required on all withdrawal points, such as wells and reservoirs, for all permits with crops that utilize frost/freeze protection quantities. This will provide accurate real-time meter readings and freeze temperatures. The District will provide funding for flow meters and installation for existing permit holders not previously required to have flow meters. Permit holders will be responsible for any maintenance or replacement of these meters. The SWFWMD plans to implement the flow meters and automatic meter-reading equipment within the next five years.

The SWFWMD also has created a new process for determining  who is responsible for responding to dry-well complaints caused by freezes. Permit holders will be assigned a "relative responsibility" based on the volume of groundwater allowed for crop protection and their proximity to the complainant’s well.

A recovery strategy aimed to meet the Minimum Aquifer Level has been established to reduce groundwater pumping for freeze protection by 20 percent within 10 years. It’s expected that such reductions would keep groundwater levels above the Minimum Aquifer Level and avoid or minimize significant impacts. District officials hope to achieve the 20 percent goal by offering financial incentives for alternative freeze-protection methods, such as tailwater recovery ponds and the use of crop covers.