The City of Stuart has one of the most comprehensive watershed improvement programs in Florida, if not the nation. Among its many benefits are water quality improvements, upland and wetland preserve areas, wildlife habitat, groundwater recharge, passive recreation, and urban open space.
The City receives an average of 60 inches of rain each year. Rain can percolate into the ground, evaporate back into the atmosphere, or become stormwater runoff. Historically in Stuart, stormwater runoff was directed to the St. Lucie River as fast as possible via ditches and underground pipes, to obtain good drainage at the least cost.
By the 1970’s, scientists began to recognize stormwater runoff was a significant source of pollution to lakes and streams. Stormwater accumulates nutrients, sediments, oil, grease, trash, etc. as it runs over the land, all of which is flushed into the St. Lucie River that surrounds Stuart on all sides. Polluted stormwater runoff is called “non-point source” pollution to distinguish it from “point sources” of pollution such as sewage treatment plants and factories.
By the 1990’s, the St. Lucie River was in serious decline due to non-point source pollution from its entire watershed, which is much larger than the City of Stuart, and includes a canal (C-44) that connects the South Fork of the St. Lucie River to Lake Okeechobee, enabling Lake O to be a dangerous source of pollution to the St. Lucie River when it discharges via C-44.
The City has long supported efforts to clean up non-point source pollution of the St. Lucie River, and committed to doing what it could to improve the quality of stormwater runoff within its jurisdiction. Stuart adopted a Stormwater Utility in 1994 to fund these efforts locally, one of the first such programs in Florida.
In 2000, the City adopted a Watershed Map. Each watershed comprises a unique area that drains stormwater within its boundaries to one or more points of discharge to tide (either via local creeks to the River, or via pipes directly to the River itself). Each watershed was studied for opportunities to improve stormwater management within its boundaries. This program became the City Watersheds Project.
The old way to manage stormwater was to drain the land as quickly as possible, with ditches and pipes straight to the Creeks and River. The City, being surrounded by the St. Lucie River at tidal elevations, and having a number of tidal creeks to drain to from mostly well-drained sandy soils at fairly high elevations, was easy to drain.
The new way is to conserve as much stormwater as possible within each watershed, holding it back with retention areas and weirs (little dams), cleaning it of pollution and releasing it slowly to tide when necessary. The new way not only cleans up stormwater before it reaches the River, it recharges the shallow aquifer from which the City derives its drinking water supply. The annual cycle of wet and dry seasons in South Florida helps, since by the end of the dry season, groundwater levels have fallen, and wet season stormwater runoff can be stored in the ground as well as in surface waters, reducing the total rainfall runoff from the land to the River.
The City’s watershed projects actually store much more stormwater in the ground than in surface waters. The same physical, chemical and biological processes that transform septic tank effluent into clean groundwater via drainfields work just as well or better for stormwater stored at the top of the groundwater table.
Surface waters are also a key element of watershed improvement projects, becoming attractive urban water features such as Frazier Lake, freshwater wetlands and wildlife habitats (Haney and Poppleton), tidal tributaries cleaned of muck sediments (Krueger, Frazier, and Poppleton Creeks), and public passive recreation trails (Haney, Frazier and soon, Poppleton). Conserved surface water can be used in many different ways to improve and beautify our environment, while improving water quality at the same time.
South Florida Water Management District has collected water quality data from 48 tributaries to the St. Lucie River since 2001, at least four of which represent City watershed project tributaries. The City has also collected water quality data. So far, the City watershed projects appear to be producing water meeting the most stringent quality standards proposed by the Florida Department of Environmental Protection and EPA.
The City’s Stormwater Improvement Program also includes recurring street sweeping in areas like old downtown where there is no room for more extensive projects, and vacuuming baffle boxes of accumulated sediments captured from stormwater at outfalls to the River and Creeks. Baffle boxes are underground concrete boxes with multiple chambers that catch trash, debris and sediments. The City has retrofit baffle boxes to every outfall, all 34 pipes, that convey stormwater from City jurisdiction directly from uplands to tide.