Last issue we talked about the components that make up our watershed; The Gulf of Mexico, Lee County Bays and Estuaries, The Caloosahatchee River and Estuary and Lake Okeechobee and we discussed the problems; Blue-green Algae, Red Tide, Red Drift Algae and Aquatic Plant Overgrowth.
This week we will discuss the causes for these problems we are facing!
The water quality issues that we are experiencing, originate from a variety of causes.
Urban storm-water runoff is one of the primary sources of pollution and it may carry fertilizers and pet waste, among other things. Agriculture run-off, aged and leaky septic tanks and releases from Lake Okeechobee are some of the more well-known causes of pollution in our waterways, but there are other sources that contribute as well, like reuse irrigation water, trash and atmospheric deposition (particles from the atmosphere).
Urban storm-water runoff
Storm-water runoff is rainfall that flows over land or impervious surfaces, such as paved streets, parking lots, and building rooftops, and does not soak into the ground.
The runoff picks up pollutants like trash, chemicals, oils, and dirt/sediment that can harm our rivers, streams, lakes, and coastal waters.
There are two types of runoff: rural and urban.
Both types of runoff can be managed through engineered structures and/or the implementation of Best Management Practices (BMP). Releases from Lake Okeechobee
Lake Okeechobee historically overflowed its natural banks, sending a sheet flow of water south through the Everglades.
Since 1928, in the aftermath of the infamous storm that drowned thousands of people, the hydrology of the lake has been changed for safety reasons, with the construction of dikes, culverts, locks and levees.
When the Caloosahatchee River became the Okeechobee Waterway, the flows to the estuary were forever altered.
The resulting nutrient rich releases have the potential to cause environmental issues and aesthetic changes in the waterways and estuary.
Septic systems, also called on-site sewage treatment and disposal systems (OSTDS), include a septic tank solid settlement and a drain field for the liquid to be dispersed into the soil for natural treatment. Solids are removed in the septic tank by settlement, and the effluent is discharged underground, where natural biological processes provide treatment in the soil.
It is important that adequate depth of dry soil not connected to the groundwater table be available for the percolation and treatment. Per Department of Health (DOH) requirements, the minimum depth is 3 feet, and without proper soil depth, the effluent would immediately impact the local groundwater.
While functioning septic systems effectively remove bacteria and reduce the water's biological oxygen demand, there is limited nitrogen and phosphorous removal. These nutrients eventually transport into surficial groundwater and have been found to migrate into nearby water bodies in coastal areas. Other Causes of Pollution
Common trash from consumer goods pollutes our waterways and oceans, threatening aquatic life and altering all types of aquatic habitats. Many items, like plastics, can persist in the aquatic ecosystems affecting the environment, wildlife, and human health.
All waste that isn’t properly disposed of has the potential to cause
Next issue.... In Part III of this series we will discuss 'What is Lee County Doing About It?'
Meanwhile check out www.facebook.com/FloridaForCleanWater
and get involved in the "hand written letter campaign."