TOOLS FOR CLEANER WATER AT MIRA LAGO

The Mira Lago community in Sarasota was built in 1991 with 183 residences housing a population of approximately 320 residents. The community has four stormwater detention ponds, Crane, Egret, Heron and Spoonbill.

In 2017 Mira Lago was hit hard during Hurricane Irma and water quality in their ponds deteriorated significantly. Seeking help, acting President Carol Auricchio applied for a grant from the Gulf of Mexico Alliance (GOMA) and received $7,000 to install BeeMats’ floating islands with aquatic plants to help reduce excess nitrogen that feeds algal growth. The floating islands did a reasonable job improving the clarity of their pond water, but ultimately proved to be too expensive to maintain and were removed. To further enhance their ponds, Carol initiated No Mow Zones around their ponds and the planting of the littoral shelves and shores with native aquatic plants.

By 2018 Mira Lago began facing some complaints from residents about the weedy/swampy look of the plants along the shoreline that didn’t look like the lakes they knew up north. Most Healthy Pond Communities have had to deal with initial resistance to the appearance of the No Mow Zone and aquatic plants in the littoral zone. However, the effort to win community acceptance at Mira Lago was particularly difficult because their ponds were plagued with unsightly algal blooms and an invasion of invasive species like torpedo grass and alligator weed on their littoral shelves.

In 2019 Carol formed the Lake Committee to help manage the pond program and deal with the community’s reservations about the aesthetic appearance of their ponds. Several different strategic approaches were employed to help change public opinion. First of all, they changed the identification of the four ponds from a bland 1,2,3 and 4 numbering system to the names of popular local bird species, Crane, Egret, Heron and Spoonbill. The new names were accompanied with educational signage placed in conspicuous viewing locations and informational events were held with local experts on pond and habitat health. Soon the ponds began attracting more birds and wildlife that helped persuade the residents that their program was on the right track. The effort also got a valuable assist from realtor, Cindy Taliaferro, who assured the residents that maintaining clear, healthy stormwater ponds is a major factor in enhancing property values.

By the end of 2019 the new healthy pond program had improved both the aesthetic look and efficiency of the ponds to such an extent that Mira Lago was selected by Sarasota County as one of four communities to be a Water Quality Champion. There was a write-up in the local press and a video on the Green Living Tool Kit highlighting their healthy pond program.

From May 2019 to May of 2020 Spoonbill Lake, one of Mira Lago’s ponds, was monitored for excess nutrients by the University of Florida’s Lakewatch program. Since the introduction of a No Mow Zone and the installation of native aquatic plants in the littoral zone, nitrogen was reduced by 23%, phosphorus was down by 26% and chlorophyll dropped by 74%.

In 2020, Charles Reith, a START Board member, took over the reins of the Lake Committee and hired Beautiful Ponds to service Mira Lago’s ponds. To fight the lingering algae problem, they recommended the use of pond dye, a blue/black dye that restricts algal growth by reducing the sunlight that algae needs to grow. This proved to be an effective approach in reducing algal blooms. The Lake Committee is also pleased with the improved water clarity as a result of their aeration system.

As is often the case with ponds over 30 years old, the ponds at Mira Lago began facing a sizeable buildup of bottom sediment or “muck” from eroded soil and plant detritus. This can be a serious problem as too much “muck” will reduce the holding capacity of the pond leading to flooding during rain events. Excess “muck” can also provide a breeding ground for various forms of unwanted algae and other aquatic invasive blooms. To reduce the sediment problem, Nathan Hoffman of Beautiful Ponds recommended the use of bioremediation, a process that uses microbes to consume the organic portion of “muck” at the bottom of a pond. This process requires an expenditure that is a fraction of the cost of mechanical dredging, is not disruptive to the pond or its banks, lowers the amount of nitrogen in the water column and significantly reduces pond sediment. The process was applied in Heron Lake and it lowered the “muck” level by an impressive 9 to10 inches in just six months. Peter Bass is now leading the work of the Lake Committee for the spring planting season.

At the end of the day the essence of the story of the successful pond enhancements at Mira Lago is that there is no one silver bullet to create a healthy stormwater pond. Rather, it is the result of a multi-pronged approach using a variety of tools to deal with a variety of situations and conditions. This includes repeated plantings in the littoral shelves and shores to maintain plant density that maximizes nitrogen absorption and provides a buffer to reduce erosion, a well maintained No Mow Zone to keep heavy lawnmowers off the banks to guard against erosion, the close monitoring of fertilizer levels to reduce the amount of nutrients running into ponds, the use of more sustainable chemical treatments to deal with algae like pond dye and, when needed, a sediment removal program to protect the holding capacity of the pond.

To learn more about how to create and sustain a healthy stormwater detention pond and to qualify for a grant to help cover the cost of the aquatic plants needed for a successful pond enhancement, contact START’s Lonnie Ready at laready@earthlink.net.

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