Lake Health - Johns Lake Association

April 1, 2019February 19, 2022

Lakefront Berms and Swales

April 1, 2019

Lakefront Berms and Swales

Rick Stuebing

Background

As more and more development occurs around Johns Lake, it is imperative that residents understand that we can have a significant effect on water quality. If we want to minimize hydrilla infestation, other invasive plants, algae blooms and pollution, we need to adhere to a few simple guidelines that will help immensely. This includes the proper use of berms and swales.

Purpose

“A berm and swale is a low hill and associated depression incorporated into the landscape, typically parallel to the shoreline. This area slows and captures runoff and allows water and pollutants to percolate into the ground. This prevents pollutants and excess nutrients from entering the lake from your yard.”

Shown below is a fairly typical depiction of a berm and swale configuration:

Here are some of the main benefits of the “berm and swale” system:

Provide a drainage path for rain and storm water runoff
Act as a filter between the water and chemicals that have detrimental effects on the lake (e.g. fertilizer, pesticides, etc.)
Provide a buffer between the lake and residential/commercial sites that have septic tanks or other potential pollutants, even drainage from swimming pools.

In order to preserve the water quality of Johns Lake we need to be responsible. Homeowners should feel a responsibility to the environment to do their part to keep the lake as pristine as possible. There are really only a few precautions and actions needed to accomplish this:

Do’s

Reduce Chemicals. Minimize herbicide, pesticide and fertilizer use. Never apply these chemicals before heavy rains. Spread mulch to prevent weeds and erosion. Identify pests before spraying and use the least-toxic pesticide available. Follow label directions for all pesticide, herbicides, and fertilizers.

Manage Yard Waste. Never blow lawn clippings into streets, lakes, or storm drains. Use leaves and pine needles as mulch. Compost yard waste and kitchen scraps. Pick up trash, litter and pet waste.

Conserve Water. Plant native or Florida-friendly plants. Turn off irrigation systems during the rainy season (June 1 – Sept. 30) or make sure your rain gauge is working properly. Install a moisture sensor on old irrigation systems, or make sure your sensors are working correctly. Direct sprinkler heads toward the landscape, away from pavement. Inspect sprinkler heads often and repair when needed.

Obtain Permits. If you plan to change anything on your lakefront like removing or planting vegetation or changing some aspect of the berm or swale, permitting will ensure it’s done properly and within guidelines. It only requires filling out a form and paying a small fee and it is the proper way to conserve our water quality.

Don’ts

Modify a Berm or Swale. Lakefront home owners should never fill in a swale and remove or relocate a berm. These features are not designed for individual properties, in nearly all cases, berms and swales are tied into adjacent properties, sometimes through whole subdivisions and for miles in some instances. Any changes made to them can negatively affect other berms and pollute the lake. Also, modifying the berm can start the process of erosion which will eventually make the berm ineffective.

Dump Chemicals in Berm or Swale. Do not dump anything hazardous into the vicinity of the berm system since this defeats its purpose. Automotive fluids, petroleum products and even drainage from a swimming pool are harmful. You should drain swimming pools slowly, on your land, and not into the berm and swale system or anywhere near the lake.

Plant Any Unapproved Vegetation in Berm or Swale. The lakeside of the berm is very important and presents the “filtered” side of runoff and drainage to the lake. Planting anything on that side of the berm that requires fertilizer or pesticide should be avoided and completely defeats the purpose of the berm and swale feature.

Never Place Anything in the Swale Do not put yard waste trash, clippings or leaves in the swale. This impedes storm water runoff and increases the amount of pollutants that would flow into the lake.

Additional Information

The berm and swale system are actually living ecosystems. As water is directed into the feature, micro-organisms thrive and support vegetation which make the berm largely self-maintaining and create a water reservoir in the system.

It may be alarming to see standing water in the swale at times (particularly after heavy rains), but this is how it is designed. The swale collects water and temporarily holds it so that any pollutants, sediments, etc. will take longer to be processed by the vegetation and soil. Water may pond in the swale for 24 to 36 hours. This is perfectly normal gives the swale more time to percolate and cleanse the runoff.

Conclusion

The picture below is a good illustration of good practices in maintaining the quality and function of a berm and swale system. No fertilizers or pesticides should be used on the lake side of the berm and eco-friendly vegetation should be maintained along the shoreline.

Older subdivisions around Johns Lake have street-side storm water drains and retention ponds that drain directly into Johns Lake. The same precautions should be used for these features as well.

Subdivisions developed after 1985 have storm water permits with SJWMD which establish an obligation to maintain the berms and swales and ensure their proper function. So, HOAs (Homeowner’s Associations) and homeowners have a duty beyond just “good practices” to keep these important features intact and unspoiled…

Sadly, some lakefront property owners are unaware of, or just disregard, the environmental standards that are the reasons behind the berms and swales. There have been instances where residents have tried to backfill the swales and/or remove the berms, or, relocate them.

If homeowner’s have any questions about regulations concerning permitting or maintaining their lakefront berms and swales they can contact

SJWMD (Saint John’s Water Management District) Customer Service during business hours at:

386-329-4570

Together, we can maintain the high quality of life we now enjoy!

February 25, 2019February 19, 2022

Invasive Plants 2019

February 25, 2019

Invasive Plants 2019

John Schmidt

The lake was treated by FWC for Hydrilla during the week of December 13th. They applied herbicide to treat some areas but did not treat the entire lake. Some hydrilla helps water clarity. They plan to use a mix of herbicides and grass carp to keep in in check. This past summer the high-water levels kept FWC from treatments. FWC is on a pause right now pending upcoming public hearings on herbicide application.

In April of 2019 FWC plans to stock approximately 1,000 sterile grass carp. Grass carp stocked into Johns Lake that would still be alive in 2019; 1,000 stocked April/May 2015, 750 stocked Feb 2016. There is no way to accurately say exactly how many of those carp stocked are alive because we don’t have perfect numbers for stocking mortality (predation by largemouth bass when they are young, etc.). We are working to get better numbers on the natural grass carp mortality curve. From what some have observed, you start to lose 10-20% per year after age 6 or so. Most do not live past age 10-12.

FWC agreed to stock an additional 1,000 carp this winter because of the way the hydrilla expanded so quickly in September. When you get the right numbers in a system you shouldn’t have to treat 1,000 acres at a time like we did in December 2018. This is no one’s fault. All systems are different, weather patterns are different, and the stocking of carp should always be in conjunction with small, sometimes frequent, herbicide treatments.

From an FWC perspective the lake looks great. We have good coverage of submersed vegetation. Water clarity is good. We are seeing an upward trend in our largemouth bass quality and noticing more ducks as well.

Some hydrilla comments:

In general, the target is 5 carp per acre of hydrilla we want to control.
FWC doesn’t want/recommend we control all of it.
There is a huge down side to too many carp because it only requires low numbers of carp to control hydrilla, if you add too many carp, they will eat all of the hydrilla and other plant species that are important to maintain optimal water quality.
There are mechanical options for removal, but they are either too expensive, ineffective, or detrimental to the native plants.

In addition, FWC was treating the oxycaryum cubense or Cuban bulrush along the shoreline around the lake where they found it during the same timeframe. Other known problem plants are Torpedo Grass.

February 25, 2019February 19, 2022

Algae

February 25, 2019

Algae

John Schmidt

You may have noticed that in some parts of the lake we have an unusual algae bloom that has many of us concerned. We’ve reached out to Orange County EPD and FWC for input/feedback. Jim Sweatman from FWC, toured the lake and on February 11 and 12 to evaluate the issue.

He was on Johns Lake Monday doing creel and Tuesday electrofishing for bass. He did notice the algae bloom in the area we reported. They did not see that type of algae bloom anywhere else on the lake and in fact, the west side of Deer Isle that hooks up to the boat ramp cove did not have a noticeable bloom, nor did the north shoreline east of Johns Cove. They reported that they had a similar winter bloom on the west side of Clear Lake last year. It took a few weeks, but it eventually went away.

When we first mentioned algae they thought we meant filamentous algae. Filamentous algae are colonies of microscopic plants that link together to form threads or mesh-like filaments. While they did notice some filamentous algae in Johns Cove and in a few places around the lake, it was not at nuisance levels.

Julie Bortles, OC Regulatory Compliance Program Coordinator has confirmed that OC does sample Johns Lake on a quarterly basis throughout the year. The last visit to the lake was February 14 and we typically sample the east and west main lobes. They will be looking at sources of nutrient pollution this year into the lake. You may want to visit the Orange County Water Atlas to look at historic trends in the lake. Overall, the nutrient pollutants look like they are trending down in a good way.

As mentioned, the areas north of Deer Island and south of Johns Cove appeared to the worst area. The rest of the lake is not impacted as much. Several comments at this point:

The areas that are the most stagnant are more vulnerable.
Many other lakes in Orange and Lake County are seeing the same thing right now.
The recent treatment of Hydrilla and the resulting vegetation decay may have added to the issue by increasing nutrient levels.
The water levels are unusually high for “dry season”.
Water Quality test results show the lake overall to be in good health.
Warmer winter water temperatures could also contribute to the additional algae.

February 25, 2019February 19, 2022

Lake Levels

February 25, 2019

Lake Levels

John Schmidt

The official recorded lake level as of January 2nd was 96.42

This is less than one foot below Normal High-Water Elevation. As you are aware this is pretty high for “dry season.”

As we’ve mentioned in prior newsletters, the outfall from the lake goes to Lake Apopka and the pathway is critical to control lake level. On one hand changes in elevation are very good for the health of the lake and fish habitat.

However, since this 39 square mile drainage basin must be capable of getting water out in periods of extreme weather, there might be some conditions that have changed that we are working to re-evaluate. On 2/19 we had a meeting with OC Commissioner Betsey VanderLey, Michael Drozeck Public Works Manager, Jeff Charles Drainage Project Manager, Mike Parker Town of Oakland Public Works Director, Steve Koontz Town of Oakland Manager and John Schmidt JLIA President to prioritize some of the issues we face on about the lake. We agreed that there is a need to update the Storm Water Drainage Basin data and particularly the flow rates. Some of the other issues we face are dependent on the results of this work and we cannot wait several years to get it done. Mike Drozeck will move this work up on the schedule and provide a timeline.

There is a Joint Planning Agreement that was signed in 2016 between Orange County and the Town of Oakland that also needs to be further developed around the “outfall ditch” to lake Apopka. The details around the specifics of who will handle the work, how easements will be obtained, who pays for the costs and so on were supposed to be worked out in three years. We are working with the various agencies to make sure our interests are taken in to account. This work is complex, will take some time, has budgetary concerns, and requires the updated study information already mentioned to be completed.

October 1, 2018April 2, 2022

Johns Lake Water Level Story

October 1, 2018

Johns Lake Water Level Story

John Schmidt

In the previous article (August 2018 Cattales), it was reported that the lake level was 99.36
NAVD88. This is incorrect due to an error in a survey benchmark used to take the reading. The correct level was 97.33 NAVD88 on September 7, 2018. Since that time, we have discovered that Orange County Survey Department takes lake elevation surveys monthly and records the official levels for all the lakes in the county. During periods of high-water, they take the readings daily. For any of you that have “stream gauges” or lake level markers you can “calibrate” your high water mark this year so far with this corrected level. JLIA is on the distribution list for these readings from now on. Sorry for any confusion.

October 1, 2018April 2, 2022

Johns Lake Tussock Issues

October 1, 2018

Johns Lake Tussock Issues

John Schmidt

A.K.A. – The Floating Islands

In April 2017, FWC toured Johns Lake with Habitat and Species personnel to see if associated marshes near the turnpike could be enhanced to increase their fishery value. On May 2, sites in the northeast side of the lake were picked for a vegetation shredding project with funding available in the FWC budget. At the end of May 2018, an FWC habitat biologist out of Eustis (Steve Crawford) contracted a company to open areas that had previously been too dense for fish habitat. The contractor used “barge-like” boats driven by paddle wheels. Attached to the boats were large metal circular “cookie cutter” blades that chopped the vegetation into fine particles that could be quickly broken down by bacteria. That project is now complete.

This project activity coupled with the high-water levels and storm winds, created a situation where some of these areas of vegetation (tussocks or floating islands) had broken free and had been floating around the lake. During the week of 10/8, FWC came back out into the lake with the “cookie cutter machine,” air boats and personnel to round up and get rid of many of these nuisance tussocks.

Next year, they hope to open areas on the south shore of the lake that have been “choked out” with the exotic torpedo grass. However, the FWC state budget next year is challenged by several projects in the southern part of the state that will take a large portion of their funding to complete. We will update the plans as more detail is available.

August 1, 2018April 5, 2022

Johns Lake Water Level

August 1, 2018

Johns Lake Water Level

John Schmidt

It’s High!

Stormwater Drainage Area, Outflow and Lake Levels

Johns Lake is located in west Orange County and east Lake County. The lake level is dependent on rainfall in an area (basin) comprised of 26 square miles. No streams or springs are known to enter the lake. This basin is located south of Lake Apopka as shown on the following maps outlined in red. The watershed includes fourteen contributing lake systems located primarily to the east of Johns Lake. Surface flow moves generally from east to west through the interconnected lake systems and associated wetlands sloughs. Discharge from Johns Lake is conveyed north to Lake Apopka through a series of cross culverts and open ditch segments. Some of the lakes that flow directly into Johns Lake are, Black Lake, Lake Tilden, and Lake Yarbo. Water levels in these lakes is generally consistent with Johns Lake.

The lake level is not controlled by any agency or group. During periods ofhigh water, the water will flow northward into Lake Apopka. (See the blue line in the current & next map) During the dry season water flow stops for the most part. The water level of Lake Apopka is on average approximately 20 feet lower than Johns Lake. Lake Apopka lake level is controlled via a series of locks and dams by St Johns River Water Management District. While they are interested in the amount of flow from the Johns Lake Drainage Area, they do not monitor it, nor the lake level.

The lake level as of 8/4/2018 was approximately 99.36 NAVD88. ( North American Vertical Datum of 1988 is the vertical control datum, or base measurement point established for surveying elevations .) The FEMA base 100 year flood elevation for the entire basin is determined to be 99.7 NAVD88. See the map below – you can use the URL listed to look at the flood elevation at your location.

Water is currently flowing about as fast as it can through the various culverts as depicted in the pictures on the following pages. One concern is that very little of the outfall canal/pathway is deeded to preserve integrity of hydraulic flow capacity and maintenance. The City of Oakland has maintained the pathway from Hwy 50 to Lake Apopka, but the pathway from Johns Lake to Hwy 50 crosses two privately owned parcels.

This is the view from the south Turnpike culvert, looking south toward Johns Lake, very over-grown.

This is the south Turnpike culvert structure. Johns Lake to the right, Turnpike to the left.

This is the view from the north Turnpike culvert, looking north toward Hwy 50, very over-grown.

This is the north Turnpike culvert structure. Turnpike and Johns Lake are to the right.

Due to recent high water, many docks are either underwater or very close. High water has created danger of submerged docks and posts. Boat wakes cause damage to structures at or nearly under water and cause boards to break free. This is costly for the dock owners and it creates a significant safety concern. Boat wakes are also causing lakeshore erosion in areas where owners have removed all vegetation, and have not planted desirable vegetation. Please be considerate, slow down and use caution as floating boards have already been spotted.

The high water is also causing vegetation to break away and create floating islands that could cause harm to boaters at night. The canal between Johns Lake and Black lake is navigable to the Greenspace Park, recently created off Avalon Road. During Hurricane Irma this canal became blocked to boat traffic with vegetation, so we worked with Orange County to get it cleared. Recently this canal became obstructed again but has been reopened. FWC (Florida Fish and Wildlife Conservation Commission) was out on the lake this weekend to survey the islands and determine the best way to remove them. If we get an update, we will be certain to update you all.

The high-water situation is unlikely to change anytime soon, and with more rainy months ahead, it will likely worsen. Looking ahead: we are in hurricane season and tropical storms could amplify the problems.

Johns Lake Water Level Fluctuations Illustrated

In a previous edition of Cattales, the variability of the water level on Johns Lake was discussed. In that article, we talked about the fact that every approximately 20 to 30 years, extreme drought conditions cause the lake level to drop precipitously and expose large areas of the lake bottom to the drying elements of sun and wind. While this has a temporary but profound dampening effect on the recreational use of the lake, it affords the lake bottom the opportunity to naturally rid itself of accumulated muck and organic materials that may have gradually accumulated over the preceding years. After a period of time the drought conditions lessen, the rains return and the lake levels are restored …but with significantly less muck and organic material on the lake bottom and a much healthier lake. The following two aerial photos were taken in 2001 and illustrate this dramatic phenomenon.

November 1, 2017April 2, 2022

Johns Lake Vegetation Mapping

November 1, 2017

Johns Lake Vegetation Mapping

John Schmidt

The vegetation in Johns Lake has been studied to understand native growth and invasive species progression and overall health. The work is conducted by Florida Fish and Wildlife Commission (FWC),
managed out of the Northeast Regional Office, under the direction of Lake County Regional Biologist, Nathalie Visscher (Nathalie.visscher@myfwc.com). FWC used to conduct the study about every
five years, using outside contractors. With recent budget changes, they now conduct a mapping study
every year with internal staff. Since Johns Lake is in Lake and Orange Counties, Lake County takes
the lead.
In late May of this year, FWC sent teams to complete the mapping for 2017. The data gathering typically takes anywhere from three to five 5 days. They utilize as many as four boats at a time, using
GPS locations, probe poles, depth soundings, and visual observation to collect the information about
the current status of the vegetation growth or decline. They will compile the data into a detailed map
to show the vegetation changes from year to year. The results should be published soon and when it
is available, we will provide a link or copy for your review

November 1, 2017April 2, 2022

Brevard County’s Indian River Lagoon

November 1, 2017

Brevard County’s Indian River Lagoon

J. Martin Davis, P.E.

….. Is it the ghost of Christmas Future for Johns Lake?

In November 2016 voters in Brevard County, by a margin of over 63 percent, approved a half-cent sales tax to provide $302 million over a 10 year period to clean up the increasingly polluted waters of the Indian River Lagoon. This water body has been increasingly threatened over the past 5 years by fish kills, algae blooms and increasing levels of nitrogen and phosphorous. About two-thirds of the money will go toward removing muck from the bottom of the lagoon, estimated to be just under 5 million cubic yards. Another $62 million will be spent for septic system removal and sewer plant upgrades to supplement the loss of the septic systems.

At the risk of being overly alarmist, could there be parallels between the Indian River lagoon and Johns Lake? Population growth and the unending appeal of living on a body of water insures that development will continue on every available developable parcel on Johns Lake, just as it is occurring on the Indian River Lagoon. And, as we’ve explored in past Cattales issues (June 2016), several of the older communities on Johns Lake are on septic tanks, albeit the more recent development have been on sewer systems. We’ve also looked at the water quality parameters published by Florida Lakewatch since water sampling for Johns Lake began in 1989. This data indicated that the water quality parameters, including the all important nitrogen and phosphorous levels, have remained relatively stable.

A clue to this serendipity may lie on the graph of Johns Lake historical water levels, included below, which was also included in the last issue of Cattales.

Johns Lake Levels 1959-2016

You will note that lake levels appear to reach very low levels at approximately 20 to 25 year intervals, as evidenced by the low lake levels that occurred in 1980 and 2001 where the low water levels were around elevation 86 or less. It’s difficult to visualize the impact of this lake level until one sees, as is shown by the included aerial photo of Johns Lake, circa 2002, just how much of the lake bottom is exposed by these drought events.

But this fluctuation of water level in Johns Lake is actually a very beneficial and helpful attribute of our lake. See, Johns Lake does not have springs or streams that provide a constant source of water into the lake. Rather our lake relies on rainfall, runoff and groundwater levels to replenish and maintain lake water levels. As such, our lake water levels are quite variable, as variable as the Florida weather.

But this is actually a major benefit in terms of maintaining water quality. During these periodic dry spells and the ensuing drop in water levels, large swaths of the lake bottom are exposed to the drying effects of sun and wind on any accumulated muck that may have been deposited on the lake bottom, drying out and blowing away the muck that otherwise might remain and accumulate indefinitely. If the Indian River Lagoon had these fluctuating water levels, it is unlikely $200 million would now be spent on muck removal.
So, we’re golden, right. With this built-in environmental lake bottom vacuum cleaner we’ve got, we’re good
to go …right? I think not so fast. 50 years ago the environmental pollutants that now affect the Indian River
Lagoon were by and large unidentified, or at least ignored. Let’s keep our collective heads up lest we suffer
the same fate.