As South Florida trends towards embracing greater environmental stewardship, there is a need to look beyond just energy and carbon intensity. Addressing the problem of water scarcity is, perhaps, even more of a priority in both the long and short term. Fortunately, there are a number of strategies that are easy to employ and may even lower water bills if properly implemented. In this post the team at Building Center No. 3 gathered some of the research on the topic as it applies to Florida and our region in order to identify trends and problems. Subsequent posts will focus on actual strategies for water conservation as it applies to irrigation.
Seasonally, the region undergoes water use restrictions enforced at the county level that are intended to preserve supplies of potable water. The restriction typically limits irrigation to twice a week for a ten minute duration.Though the rates for water supply in Miami Dade are relatively affordable compared with other cities around the State and across the country , the need to manage expenses has remained a priority in this economy. Miami Dade Water and Sewer Department charges $2.24 for every 749 gallons of water (within the usage range of 4500 – 6700 gallons) .
Sources of Freshwater
There are two sources of freshwater: groundwater and surface water. In 2005, when the most current data was available , Florida sourced 61% of its freshwater from groundwater supplies. There are four groundwater aquifer systems in the State and Miami Dade and Broward withdraw from the Biscayne Aquifer that spans from the southern most tip up of Miami Dade to a southern portion of Palm Beach County.
Water use in the State is organized by:
- public supply (which includes residential)
- commercial-industrial self-supplied
- power generation
- domestic self-supplied
- recreational irrigation (golf courses and parks)
- agricultural self-supplied
In the State of Florida 60% of the public supply is used for domestic ends with Miami Dade as its largest consumer and trends show that the consumption rate (correlated with population growth) is increasing.
Some studies have shown that in Florida irrigation represents 60% of domestic water use for a single family home. The Alliance for Water Efficiency estimated that, nationally, the remaining 40% is typically used for various indoor household uses such as flushing, dish washing, bathing and even unrepaired leaks .
Inefficient Use of Irrigation
Research in Florida has shown that homes using the ubiquitous above-ground sprinkler systems on timers generally over-irrigated their landscape by 2.4 times the calculated irrigation need . With irrigation at 60% of total water use, eliminating over-irrigation could represent a modest cost savings in addition to the environmental stewardship that good water conservation practices engenders.The next post will focus on available residential sources of water for irrigation in order to reduce the consumption of freshwater.
1 Miami Dade County WASD Rate Comparison Accessed May 30th, 2011 http://www.miamidade.gov/wasd/rate-compare.asp
2 Miami Dade County WASD Rates, Accessed May 30th, 2011 http://www.miamidade.gov/wasd/rates.asp
3 Water Withdrawals, Use, and Trends in Florida, 2005; Richard Marella; USGS
4 Alliance for Water Efficiency, Accessed May 30th, 2011 http://www.allianceforwaterefficiency.org/residential-end-uses-of-water-study-1999.aspx
5 Residential Irrigation Water Use in Central Florida, Journal of Irrigation and Drainage Engineering, 2007. Melissa Haley, et. al.