Excerpted from TBO.com Published: June 16, 2011
January 2010 The Southwest Florida Water Management District (Swiftmud (SWFWMD) reported that Strawberry farmers in 11 days to protect their berries from freezing pumped millions upon millions for water on their berries.
The farmers lowered the aquifer so much that it also dried up 750 residential wells, besides causing 140 sinkholes, in Hillsborough County/Dover/Plant City.
Therefore, Swiftmud implemented new rules:
New water pumping rules for farmers take effect today, 16/Jun/2011
There is now a 256 sq mile water-use caution area, and Swiftmud has awarded $1,900,000 in cold protection alternatives to help five area strawberry farms reduce their groundwater consumption, particularly for freeze protection. This measure will help reduce groundwater withdrawals in eastern Hillsborough County by 550,000 gallons per day on average, and the additional 18,000,000 million gallons on days when water is needed for frost/freeze protection.
Swiftmud is paying up to 75 percent of the cost for such water-conserving measures as creating ponds that will collect water that drains from farms so it can be used for irrigation.
Farm ponds can significantly offset farmers reliance on purchased water (or cost of permits).
Example: One calculation in Pennsylvania showed that a 2-acre clay-lined pond with an average depth of 7 feet will provide roughly 10 acre-feet of irrigation water, accounting for loss to seepage and evaporation. For a vegetable crop that requires 4 inches of irrigation water, this 2-acre pond will irrigate 30 acres of crop.
Ponds also present an opportunity to store water in ways that can have other beneficial effects on water supply for farmers, fire protection, and as well, the environment. For example, seepage from ponds can recharge groundwater and help to offset pumping from groundwater basins. Irrigation in its self also recharges the Aquifer. In this sense, ponds act to slow the flow of water through the basin reducing flooding, allowing more of it to be retained for use. In a clay soil-lined pond, seepage of only 500 gallons/day is considered excellent and 1,000 gallons/day good, so even in these cases the ponds will augment groundwater supplies throughout the year.
However, in Florida due to the soil types in these areas would require more prudent pond linings. Due to the lack of clay in Florida soils there are catalysts that can be engineered into the compacted soils lining the pond. For instance; Bentonite can be added to engineered soils for pond lining in areas which never dry out.
Using waterproof linings is another method of reducing excessive seepage in both coarse-grained and fine grained soils. Polyethylene, vinyl, butyl-rubber membranes, and asphalt-sealed fabric liners are gaining wide acceptance as linings for ponds because they virtually eliminate seepage if properly installed.
For purposes of comprehension of magnatudes:
The average in-ground swimming pool volume; 16x34x5’ uses 20,400 Gallons 2727 cubic feet of water or 0.063 acre feet
(In-ground pool estimated costs are $7,000,00-$16,000 for a vinyl-lined model, $15,000-$25,000 for a fiberglass shell and $170-$45,000 for concrete or gunite.)
(Cost estimates unknown)
Relating to the text above: 1 acre = 43560sq ft x 2 acres = 93120sq ft x 7 deep = 651840 cubic feet, 651840 cubic feet = 15 acre feet (theoretically, 5 acre feet loss due to seepage and evaporation.)
550000 gal = 1.688 acre feet
11 days x 18,000,000 gallons = 198,000,000 or 608 acre feet of water to save the Strawberries.
This all relates to Rain Water Harvesting, but in a massive scale! It can also provide a lot of wildlife habitat resources, fishing resources, and other recreational job resources.