Smithsonian Marine Station at Fort Pierce

Website Search Box

Advanced Search

The Indian River Lagoon (IRL) (Fig. 1 & 8) is one of the most biodiverse estuaries in the United States and directly impacts all of us who live within its watershed on a daily basis. Critical to IRL’s remarkable biodiversity is its water quality. Why is water quality so important? Maintaining high standards of water quality, among other things, supports healthy seagrass beds. Seagrasses serve a vital role in the ecology of the IRL. Not only do healthy seagrass beds oxygenate the water column and stabilize sediments, but perhaps most importantly, they also provide a critical nursery and refuge area for juvenile fish and invertebrates, many of which are commercially important. Seagrasses also serve as a food source for many IRL inhabitants either directly (e.g., Thalassia testudinum consumed by sea turtles) or indirectly (epiphytes living on seagrass blades consumed by small fish and invertebrates).

Negative impacts of poor water quality include declining seagrass beds and shellfish harvests as well as an increase in harmful algal blooms and fish kills. Keep in mind that if your home occurs within the IRL watershed (see Fig. 2), you have a direct effect on its water quality.


Fig. 1. Early morning on the Indian River Lagoon, Sebastian, FL. Photograph by J. Reed


Fig. 2. The Indian River Lagoon watershed (defined by purple outline). Graphic courtesy of Florida Department of Environmental Protection.

Putting a dollar value on the importance of maintaining a healthy IRL ecosystem, we need to consider the following. Seventy percent of Florida’s economy is directly linked to its coastlines. The Indian River Lagoon runs approximately 156 miles spanning one third of Florida’s east coast. In 2007, the estimated economic value of the Indian River Lagoon was $3.7 billion dollars. The estimated 2007 economic value of the IRL’s 72,400 acres of seagrass supporting recreational and commercial fisheries was valued at $ 329 million dollars per year (or $4,600 per year per acre of seagrass).

Below are five pro-active ways in which we all can help to effectively improve water quality in the IRL thereby enhancing its biodiversity, economic value and aesthetic appeal:


1. REDUCE FERTILIZER USE

2. SEND ONLY RAIN DOWN STORM DRAINS

3. PICK UP AFTER OUR PETS

4. USE THE RIGHT PLANT IN THE RIGHT PLACE

5. LEAVE ONLY FOOTPRINTS


Let’s take a few minutes to learn why these measures are important and what we can do to improve water quality in the IRL. We will all benefit from these actions!


Indiscriminate use of fertilizers results in deteriorating water quality in the Indian River Lagoon as well as waterways everywhere. Fertilizers are composed primarily of nitrogen, phosphorus and potassium which are the major components required for plant growth. These chemicals, when improperly used, can have significant adverse effects on the environment.

Although fertilizers can temporarily make a lawn look greener, they are far too often applied incorrectly. Instead of being incorporated into plant tissue, excess nutrients work their way into the lagoon directly through stormwater runoff or indirectly by seeping through the soil into groundwater. When in the lagoon, these nutrients stimulate blooms of micro-algae (i.e., phytoplankton) as well as the proliferation of other aquatic plants. Blooms of certain species of phytoplankton can create what are known as harmful algal blooms, i.e., "HABs". HABs can produce potent toxins that can have negative health consequences for both humans as well as marine organisms.

Eutrophication is a process in aquatic systems that describes the subsequent decay of rapidly growing plant material consuming available oxygen, thus creating hypoxic conditions that threaten other plants and animals in the ecosystem. Larval and juvenile stages of fish and invertebrates can be particularly sensitive to eutrophication. This decaying organic material eventually settles to the bottom and, along with fine particles of silt and clay, creates a low oxygen (hypoxic) layer often called muck. Hypoxic conditions can affect biodiversity by causing the demise of species normally found in an area while promoting the growth of opportunistic species that thrive in low oxygen environments. Muck can easily be resuspended and further affect water quality and clarity. Dense phytoplankton blooms (harmful or otherwise) can also physically decrease the amount of light penetrating the water column and thus pose as an additional threat to healthy seagrass growth.

Fig. 3.

How We Can Minimize the Adverse Effects of Fertilizer

Become familiar with the Florida Yards & Neighborhoods (FYN) Homeowner program, sponsored by the University of Florida (UF) Cooperative Extension service and supported by UF/Institute of Food and Agricultural Sciences (IFAS). This program educates homeowners about the design, installation, and maintenance of healthy landscapes that use a minimum of water, fertilizer, and pesticides with the hope of preventing residential yards from becoming a source of groundwater pollution. Among the nine principles outlined in The Florida Yards & Neighborhoods Handbook, 4th ed., http://fyn.ifas.ufl.edu/materials/FYN_Handbook_vSept09.pdf, number three addresses appropriate use of fertilizers and recommends the following:

  • Fertilize according to UF/IFAS recommended rates and application timings to prevent leaching. Please see the following website for FAQ’s and recommended dosages(http://edis.ifas.ufl.edu/wq143). Also visit http://www.swfwmd.state.fl.us/yards/fertilizing/ for tips on Florida friendly fertilizing and download a free publication: A Do-It-Yourself Guide to Florida-Friendly Fertilizing.
  • Look for fertilizers with slow-release nitrogen and little or no phosphorus. In Florida, phosphorus, occurring as phosphate, is abundantly and naturally available in sedimentary rocks and soil.
  • Never fertilize within 10 feet of any water body.
  • Do not fertilize before a heavy rain. Sarasota and Lee Counties have banned the application of fertilizer during the rainy (summer) season (1 June – 30 September) and Sarasota County goes further by prohibiting the sale of fertilizer during the summer.
  • Sweep up spilled fertilizer and return to original package.
  • Use iron supplements (ferrous sulfate or chelated iron) on turf instead of nitrogen fertilizer to achieve a quick summer green-up.
  • Avoid “weed and feed” products that contain both fertilizers and herbicides, these can damage some plants.
  • Always follow directions on the fertilizer label (Fig. 3).
  • If reclaimed water is used for irrigation, be aware that it does contain some nutrients. Adjust the amount of fertilizer accordingly.

The majority of rainwater from impervious surfaces such as paved streets, parking lots, sidewalks and rooftops as well as from saturated fields and slopes lacking vegetation, is collected by storm drains, swales (shallow, grassy channels that collect stormwater from streets and sidewalks) and retention ponds. This stormwater runoff often enters canals and tributaries that drain directly into the Indian River Lagoon (Fig. 4). For example, it is estimated that 75 billion gallons of stormwater runoff in Brevard County makes its way into the IRL annually. Carried with this runoff are pollutants such as heavy metals, fertilizers, sediments, animal wastes, oil and grease from roadways ,anti-freeze, pesticides, household chemicals, bacteria, and an array of organic and inorganic material.

In the IRL, these materials threaten water column and bottom dwelling organisms, promote excessive algal growth, and can smother seagrasses. This “non-point” pollution is the primary source of pollution in the IRL today and poses the biggest threat to its water quality. A common misconception hindering individual efforts to lessen the effects of this pollution source is that many of us think that water entering storm drains is initially directed to wastewater facilities for treatment. This is not the case.

Fig. 4. Posted signs such as this remind us why it is important to keep stormwater runoff clean (with permission, D. Wilson, Indian River County)

To help keep sediment, leaves, yard clippings, and floating litter that would normally reach the IRL via storm drains, many local governments as well as the Indian River Lagoon National Estuary Program have been instrumental in installing a number of stormwater treatment devices known as baffle boxes throughout the IRL. Although baffle boxes do not remove dissolved nutrients, this inexpensive, relatively simple technology has been tremendously successful in preventing much solid material from entering the lagoon.

Despite these efforts, we still need to do more as individuals to keep stormwater runoff as pollutant free as possible.

How We Can Help Keep Stormwater Runoff Clean:

  • Use fertilizers (see above) and pesticides according to the directions on the label. Pesticides that eradicate terrestrial insects often adversely affect aquatic crustaceans (e.g., copepods ,shrimps, lobsters and crabs), particularly larval stages. After all, they are all arthropods!
  • Dispose of used motor oil, paint, and other chemicals at designated locations. Never let these materials enter storm drains.
  • Dispose of animal wastes properly (see below).
  • Dispose of garbage in proper receptacles.
  • Use native Florida plants in landscaping (see below) to minimize irrigation, reduce use of fertilizers and pesticides, and to avoid proliferation of non-native, invasive species.
  • Recycle or properly dispose of yard wastes (leaves, pine needles, grass cuttings, etc.)
  • Use rainbarrels and rain gardens to capture stormwater runoff from roofs, etc.
  • Wash your car at a commercial car wash or on your lawn – never in the driveway.
  • Report runoff from construction sites and illegal dumping and discharging to the appropriate stormwater agency in your county.
  • Keep neighborhood storm drains free of debris. Participate in approved storm drain marking projects in your municipality.

We all love our pets and treat them like family members. If we do not pick up after our pets, we are doing a disservice to them, ourselves, our neighbors and the environment. Neglected pet waste poses a major bacterial pollution threat to the Indian River Lagoon when it enters local waterways and works its way into the IRL via stormwater runoff.

The Humane Society of the United States estimates that 39% of all households own at least one dog. Based on this national trend, it is estimated that in Brevard County alone, there are approximately 104,832 dogs. Dogs produce about one pound of waste per day. This material contains fecal coliform bacteria (one gram of dog waste contains about 23 million coliform bacteria) including salmonella. This material may also contain viruses and parasites such as roundworms, hookworms and tapeworms. Many of these organisms present a potential human health hazard and can cause severe cramping and diarrhea, particularly in children and the elderly. These organisms can linger in the soil for years if associated animal waste is not disposed of properly. In urban areas, dog waste is also a potential source of food for mice and rats. Rodents can carry a host of harmful bacteria and be a source of ticks and fleas.

Some people are reluctant to pick up after their pets for a variety of reasons: inconvenience; unsightliness; odor, etc. Although more than 60 % of dog owners do pick up after their four-legged friends, it is estimated that in the five county region surrounding the Indian River Lagoon, every day, as much as 167,530 pounds (84 tons) of dog feces is left on the ground in backyards, sidewalks and streets. In addition, some misinformed citizens will dispose of animal waste directly into waterways and/or storm drains. Since most stormwater is not treated before flowing into canals and local waterways, bacteria and other organisms in neglected or improperly disposed of pet waste can directly threaten commercial and recreational fishing, shellfishing, boating, and swimming in the Indian River Lagoon. Nutrients associated with pet waste can also cause the proliferation of phytoplankton and macro-algae with additional, adverse effects on the IRL ecosystem (see above).

Fig. 5. Picking up after our pets can significantly reduce bacterial pollution in the IRL. Photograph (A) by A. Dubin. Pet sanitation station (B) at a St. Lucie County dog park.

What We Can Do As Responsible Pet Owners

  • Don’t leave pet waste in your yard to become a health problem.
  • Pick up dog waste preferably in a biodegradable bag. Many area dog parks are equipped with sanitation stations that dispense dog bags (Fig. 5 B). This material may then be disposed of in the trash, flushed down the toilet or buried in a hole approximately six inches deep.
  • Dispose of cat waste and litter properly: carefully remove solid waste from the litter box and flush down the toilet; bag used litter and dispose of in the trash
  • Clean up any waste near storm drains, ditches, wells and waterways.
  • Avoid letting your pet defecate near waterways that drain into the IRL.
  • Do not compost pet wastes because of potential human health threats.
  • Use a commercial sanitation service if you do not want to pick up after your pet.

Most of us take pride in creating and maintaining the landscape surrounding our homes. Landscaping increases the aesthetic and curb appeal of our dwellings and enhances property value. Florida’s nursery and landscaping industry is big business, significantly affecting Florida’s economy by creating thousands of jobs and impacting labor income. In 2005, landscape sales topped $5.25 billion and sales from retail garden centers were estimated at $6.97 billion.  The practice of planting the right plant in the right place can be consistent with promoting these economic benefits.

The idea behind using the right plant in the right place is to choose landscaping plants that fit best into existing site conditions, thus minimizing the use of fertilizers, pesticides, irrigation and labor. When these commonly used “backyard chemicals” are eliminated, or applied at minimal rates, and less water is used for irrigation (waterwise landscaping), the likelihood of these chemicals reaching the Indian River Lagoon through stormwater runoff and adversely affecting IRL water quality decreases.

In fact, one of the biggest uses of water in Florida is for lawn and landscape irrigation. Because of ever changing cycles in Florida’s natural water supply, water conservation through waterwise landscaping in conjunction with prudent use of fertilizers and pesticides is something we should all strive to achieve.

Florida Friendly LandscapingTM, http://fyn.ifas.ufl.edu/, a University of Florida IFAS extension website, advocates nine principles to encourage and promote environmentally sustainable landscaping practices. First on the list is RIGHT PLANT, RIGHT PLACE.

Fig. 6. Native Florida Plants: (A) Climbing aster, Aster carolinianus, with great southern white butterfly, Ascia monuste.Photograph by V. Lamb; (B) Sea ox-eye daisy, Borrichia arborescens, a carefree, drought and salt tolerant shrub. Photograph by C. Deschene. Note bee in inset. Photograph by K. Skurtu.

How We Can Choose the Right Plant for the Right Place:

Before choosing specific plants, a few general landscaping principles to keep in mind, detailed in the Florida Friendly Yard handbook available at http://fyn.ifas.ufl.edu/materials/FYN_Handbook_2015_web.pdf include:

  • Choose low maintenance plants (Fig. 6 B).
  • Choose flowering and fruiting plants that attract wildlife (Fig. 6 A).
  • Plant for visual impact by grouping plants together.
  • Do not choose and/or eliminate non-native, invasive plants in your yard.
  • Choose healthy looking plants.
  • Consider the size of a plant or tree when fully matured, not when it is purchased.
  • Choose a diverse array of plants, shrubs, trees, etc. A diverse plant community is less susceptible to disease and insects.
  • Consider groundcovers as opposed to grass on slopes for easier maintenance.
  • Avoid “Quick Fixes”. Slow growing as opposed to fast growing plants will take longer to fill your landscape, but they will last longer and require less maintenance.
  • Consider the wind. Certain species of trees are more susceptible to strong winds.
  • Consider upkeep and realistically determine how much time you would like to, or be able to spend in the garden!

When you are ready to choose specific trees/plants for your individual landscape, there are several resources that are particularly helpful:

  • The Florida Friendly Landscaping website, http://www.floridayards.org/ , consists of four components, including a searchable plant database, to encourage and enhance low impact Florida landscaping.
  • The following website, published by St. Johns River Water Management District, http://publicserver2.sjrwmd.com/waterwise/search.jsp, allows one to choose specific plants and trees by common or scientific name based on desired height, flower color, soil moisture, pH, light regime, salt tolerance and growth rate. One can download the website on a smart phone at the nursery, plug in values for the above parameters, and determine the appropriate plant.

The Indian River Lagoon is renowned for its natural beauty and array of habitats, offering residents and visitors alike a host of opportunities for engaging in outdoor, recreational activities (Fig. 7). Fishing, boating, kayaking, canoeing, hiking, camping, sightseeing, wildlife viewing, and photography are some of the fun, adventurous activities we all enjoy on the waterways of one of America’s most biodiverse estuaries.  

In 2007, recreational expenditures related to the Indian River Lagoon by residents and visitors were valued at $1.3 billion. Recreational use value, i.e., the amount of money people would be willing to spend to recreate on the lagoon, in addition to recreational expenditures, was valued at $762 million (http://floridaswater.com/indianriverlagoon/pdfs/IRL_Economic_Assessment_2007.pdf).

In order to preserve and maintain the biodiversity and integrity of the IRL for ourselves and future generations to enjoy, let us now become better stewards of the lagoon. Let us give more thought as to how we can reduce our impact on, and respect the IRL ecosystem during our outdoor activities on the lagoon by “leaving only footprints”.

Fig. 7. Recreational opportunities abound on the Indian River Lagoon. Photograph by P. Lilienthal.


Leave Only Footprints - What We Can Do:

Leave No Trace (http://www.lnt.org/programs/index.php) is a website dedicated to educate outdoor enthusiasts on how to minimize their impacts on the environment. Visit the website for scientifically based, common sense, ideas on how to maximize enjoyment of your outdoor outing while protecting the environment. Their principles, bulleted below, are adaptable and applicable to Indian River Lagoon adventurers.

  • Plan ahead and prepare.
  • Respect wildlife.
  • Leave what you find.
  • Dispose of wastes properly - “pack it in, pack it out”.
  • Be considerate of other visitors, present and future.
  • Travel and camp on established trails and campsites.
  • Minimize campfire impacts.
Fig. 8. Indian River Lagoon sunrise. Photograph by E. Comes.

We all have a vested interest in the Indian River Lagoon. Let us all become more aware that our environmentally responsible actions taken today, individually and collectively, can and will make a big difference in preserving this national treasure for ourselves and future generations.


[ TOP ]