AUGUST 2016 LAKE REPORT UPDATE

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1 AUGUST 2016 LAKE REPORT UPDATE As a continuing effort to ensure SPOA members are informed of activities in which the Board has engaged within our community and to provide additional information for future decisions that may require membership vote, this Newsletter is being posted. Sundowner Lake Water Quality As you will recall from the July 2016 SPOA Newsletter Update, we indicated that we had contacted Clear Water Consulting out of Magnolia, Texas, and shipped to them three water samples taken from different areas of the lake for laboratory analysis. Knowing the levels of contaminants that may be contributing to the algae problem will help us understand what would comprise an effective control plan. We have received the laboratory report (see water analysis report next page) and discussed the results with Clear Water consultants. Clear Water indicated that for the most part, the water parameters analyzed were within acceptable limits. The ph tested slightly acidic (5.54 versus an optimum 6.9 for healthy fish populations), but that is what would be expected after the heavy rains we received earlier this year. Normal rainwater has a ph of 5.6 (slightly acidic). This is because it is exposed to the carbon dioxide in the atmosphere. The carbon dioxide gets dissolved in the rainwater and forms carbonic acid (H{-2}CO{-3}). Rainwater with ph value below 5.6 is considered as acid rain. Water hardness was also noted to be limiting in the lab report, indicating a hardness level of 1 grain of Calcium Carbonate (CaCO3)/gallon, or 22 parts per million (ppm) CaCo3. Grains per gallon (gpg) is a unit of water hardness defined as 1 grain (64.8 milligrams) of calcium carbonate dissolved in 1 US gallon of water ( L). It translates into 1 part in about 58,000 parts of water or 17.1 parts per million ((1 mg/l (ppm) = grains per US gallon)). Calcium and magnesium ions present as sulfates, chlorides, carbonates and bicarbonates cause water to be hard. Water chemists measure water impurities in parts per million (ppm). For understandability, hardness ordinarily is expressed in grains of hardness per gallon of water (gpg). According to the Water Quality Association, water hardness is considered to be the following: soft: grains per gallon (gpg), moderate: gpg, hard: gpg, and very hard: over 10.5 gpg Basically, we have soft water and that relates to the ph as the level of CaCo3 in the water. Soft water lakes and ponds seldom support abundant fish or plankton populations. Plankton, the basis of the food chain, often is limited in acidic waters with low alkalinities. Surface waters with low alkalinities typically are acidic and infertile; few dissolved nutrients are present and most nutrients are locked onto acidic bottom muds. Limestone neutralizes acidic bottom mud (i.e., increases soil ph) and promotes the release of phosphorus and other limiting nutrients needed for photosynthesis by green plants.

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3 Liming surface waters neutralizes acidity and increases ph, alkalinity, and hardness to levels that encourage plankton and sport fish growth. Liming not only adds calcium, but releases absorbed elements (phosphorus and carbon) important to the growth and support of aquatic life. The ph and hardness of our lake could be raised by adding agricultural lime (finely ground aglime - CaCo3) to the lake. Although aglime is relatively inexpensive (Internet quotes for bulk aglime range from $60 to >$100/ton depending upon transportation costs), the downside is that the typical application rate for acidic waters is 1-2 tons of aglime per surface acre for initial liming. That would equate roughly to 50 to 100 tons of aglime initially for our 85 surface acre lake. Calculating exactly how much limestone to add to neutralize an acidic lake is complicated by many factors, including: existing ph, alkalinity, and hardness acidity and chemistry of lake bottom mud water quality and temperature desired ph and target water quality density and types of aquatic plants type, purity, and particle size of the limestone volume and flushing rate Product cost of $3,000 to $10,000 would not include application. Buying bagged, granulated or pelletized lime for local application by SPOA volunteers would triple the product cost. Liming is recommended to be conducted in late August. Typically, a barge of sufficient displacement is used to move the lime into position where is shoveled or washed off into the lake. Clear Water Consulting indicated that they had all such application equipment for $2,200/day plus travel mileage. This is not, in our opinion, an inexpensive venture and because every lake is different, we may want to consider the services of a local consultant as discussed later in this report before any actions are undertaken. Regarding volume, retention and flushing rates, another downside to liming is the very real possibility of needing to relime. If we have another year of heavy rains like we did from December through April and experience high levels of flushing (spillways), we will likely be back to square one regarding lake acidity. Lyngbya (Filamentous) Alga We are all aware of the recurring alga that currently plagues our shoreline. We won t belabor the scientific descriptions in this update except to briefly state that Lyngbya is not a plant, fungi, bacteria or a true alga. It is actually a primitive form of life called Cyanobacteria, a blue-green algae capable of photosynthesis even in low light conditions. Lyngbya lives in both saltwater and freshwater. It forms long filamentous hair-like strands that mat together in thick layers along the bottom of waters, sometimes as much as 5 feet thick. It can rise feet from the water s bottom up to the surface. It is slimy to touch because of the mucus-like coating it produces. Large floating mats of lyngbya rise to the surface because of the gases released by the bacteria that live inside the mats that deplete oxygen from the water. Reproduction occurs by the formation of hormogonia, a portion of filament that detaches and reproduces by simple cell division. Lyngbya is a worldwide problem with no simple solution for permanent removal. There is much information available on the Internet regarding methods of controlling lyngbya, albeit none conclusive or universally applicable to individual lake or river conditions. As discussed in the July Newsletter Update, previous attempts SPOA August 2016 Lake Report Update Page 3

4 by SPOA to spray the alga with copper sulfate solutions (most common form of chemical control), including repeated applications over a two year period by a Board member around his dock, produced disappointing results. As we indicated, there is no simple, universally applicable or inexpensive solution for controlling the lyngbya. Clear Water Consultants indicated that they would use enzyme enriched, copper sulfate granules or solution, with initial shoreline and secondary spraying if needed for about $10,000. This would most likely turn into an annual expense. Organic control, i.e., introduction of grass carp and/or Mozambique Tilapia, is expensive, not guaranteed and would also become an annual expense as tilapia would have to be restocked after cold weather fish kill. Recommended quantities vary between pounds per lake surface acre. At 2-3 tilapia/pound and at a cost of $8-12/pound, the effort would present an expensive option with no guarantee of success. In response to our July Newsletter talking about reported successes with tilapia at Lake Greenbriar (Holly Lake Ranch), we received this from Mr. M. G, Johnson Jr.: Hi, I suspect I might have been the one that was alluded to in the latest report that said tilapia had worked at Lake Greenbriar in Holly Lake Ranch. My son and I both have lots at Sundowner and used to come over regularly. However, since I bought a lot and had a dock built on Lake Greenbriar I and my son do not come as often. I own the blue boat behind the little pavilion next to the dock. I have owned the lot at HLR since the fall of The lyngbya algae seemed to major in my end and side of the lake. It was awful and really hopeless to do anything with. The depth of water near my dock seemed just right for it. I had lobbied the fishing club since 2009 when I bought a house to see about getting some tilapia since I knew they apparently had been successful at Lake Lydia. Lake Lydia also had some grass carp which were huge the last time I saw them. Lake Lydia is a very clean lake. The golf course is very important to some at HLR and when the lyngbya got into one of the golf course ponds they decided to put some tilapia in. Well they cleaned the thing out. At some point this year tilapia were introduced into the 330 acre lake. It was not announced for some reason. All I know is one weekend I walked out on my dock and there was no more lyngbya. It had been stated they were to be introduced but I did not know they were in yet. However, I figured that was where the lyngbya had gone. I have been told they will also eat the muck on the bottom but I think they have to run out of other things to eat. In throwing some catfish pellets out for sunfish I noticed a bunch of swarming fish I had never seen before. Tilapia seem to love catfish pellets and they are very aggressive feeding. At the point a few months ago when I noticed them they were probably less than 0.5 pounds. In a month or two they have really grown. I caught one that was 0.75 pounds. They are very fat. You can catch them on worms but the sunfish get to the worms first although my wife caught one on a worm. One can catch them on catfish pellets fished at the surface. It is tricky since if the pellets are very dry they are hard to get on the hook but manageable with a small hook. I obviously throw the things back but some day if they are threatened by cold water then there can be a tilapia harvest. I believe that is what Lake Lydia used to do when they got lethargic and came to the surface. I doubt if HLR put 20 pounds of fish per acre into Greenbriar although they may have. I guess someone can call the HLR office and talk to the manager and see what they did do. Lake Lydia has a lake manager and someone could call him and see what their experience is. SPOA August 2016 Lake Report Update Page 4

5 Although I do not think tilapia really do much to control lily pads they do seem to eat the buds. I and some others noticed flowers missing and that may be why there was not a big announcement of their going into the lake. Some may like their lily pad blooms. My lily pads do not seem to have been trimmed back although they may not be spreading. M. G. Johnson, Jr. Upon receipt of Mr. Johnson s , we contacted Mr. Jim Horn, General Manager, Holly Lake Ranch. Jim had very positive things to say about the introduction of tilapia for control of the alga. He stated that they first introduced tilapia into the golf course water hazards that had developed lyngbya growth, and after success with controlling those ponds, introduced tilapia into Lake Greenbriar. When asked about specifics, Jim said that one of the local residents made all arrangements, was out of town until the end of August, but remembered writing a check for $5,000 to cover the cost. Jim also stated that after the fall/winter fish kill, the dead tilapia had to be harvested from the lake with boats and nets. Opinions of effectiveness also vary. We also contacted Mr. Lawrence Terry, Lake Manager, Lake Lydia, Inc. As you will recall, Mr. Terry prepared a pro bono report with some maintenance recommendations for our dam following the heavy rains earlier this year. In an effort to provide SPOA members with as much information as we have collected thus far, Mr. Terry s rather detailed history of Lake Lydia management is presented below: Mr. Stewart, Thank you for your response, I hope my short report helped in clarifying some issues in need of attention on the dam. Regarding using Tilapia to control Lyngbya (AKA: Filamentous) Alga, I have mixed opinions on the issue because of unforeseen consequences during and after the time we stocked Tilapia. For many years before 2008, we had been using Biologist Stan Smith of Tyler, who owns Aquatic Management Services (AMS), for completing a survey of our lake's water quality and aquatic weeds and establishing fish population ratios by electro-shock means every 4 th year. With his recommendations, our fishing and the relative-weights of our game fish have increased greatly and our eco-system has never been better. Biologist Stan Smith has 40+ years of experience and works as a research Biologist with the Texas Parks and Wildlife on many studies, including ways and means of combating and controlling Lyngbya, in which they have had very little luck and success after many years of studies. As you may know, once you have Lyngbya it is all but impossible to get rid of without the repeated use of copper-sulfate in liquid, crystal or pellet form but because of its cost makes it's all but impossible for use by small lakes, secondly, if not used as recommended, it can be very harmful to fish populations. This link has useful information and links to the permit needed for Triploid Grass Carp. ( In 2008, a Lake Committee Chairman we had at the time, chose to disregard the recommendations of Biologist Stan Smith and had a different lake management company from south Texas come in and complete what turned out to be a half-hearted survey. In that survey, they recommended the use of 15 to 20 pounds of Tilapia per surface acre to control Lyngbya Algae and 10 to 20 Triploid Grass Carp per acre to control the Hydrilla in our 94 surface acre lake, of course, to be purchased from their fisheries. The south Texas company's recommendations were instituted by that Lake Committee Chairperson 04/01/2008 through 03/01/2010, against my repeated objections and in short, it all but ruined our lake and fish populations. During that time period, nearly $ 26,000 was spent on over 3,000 pounds of Tilapia and $3,800 on 500 Triploid Grass Carp, with the Carp stocking being half (500) of the 1,000 recommended because of my constant objections. As a result, these were the most obvious effects and ramifications to the lake: (1) The most obvious ramification of Tilapia use, was in the fall of each year the Tilapia died off, most floated to SPOA August 2016 Lake Report Update Page 5

6 the surface, created smelly mats of fish along the shorelines, then ended up in our spillway intake channel where we had to use half, 55 gallon barrels to collect and carry them away; (2) The use of Tilapia had almost no noticeable effect on our Lyngbya problem which we believe was due to the abundance of other food sources. We still had a large amount of Lyngbya mats along the shorelines even during the years stocked; (3) The other unforeseen ramification of Tilapia use, an unmentioned by the south Texas company, for using of Tilapia was that their secondary source of food (which we found was actually their first food choice in our lake) was mosquitoes and mosquito larva, which is a good thing, however, they also consumed other larva, microorganisms, small minnows, tadpoles and frogs; (4) On the stocking of 500 of the recommended 1,000 Triploid Grass Carp in 2008, they did bring the Hydrilla under control within two (2) years, but with drastic consequences to other beneficial aquatic plants. On item #3, where the Tilapia consumed other larva, micro-organisms, small minnows, tadpoles and frogs, this devastated the base of our food chain in the lake, plus we had almost no frogs in the lake until just last year when they started making a comeback. In the years 2011 and 2012 we had large Catfish and numerous Bass floating up dead from starvation because the base of the food chain had been destroyed, thus destroying other forage fish populations such as Bream and Shad. On item #4, after the Triploid Grass Carp brought the Hydrilla under control, they turned to consuming almost every submerged plant and some emergent aquatic plants, including Maiden-Cane and other very beneficial grasses which enhanced fishing along the shorelines. Now some seven (7) or eight (8) years later with their eating habits being retarded due to age, we are just now getting the beneficial plants back and the fishing has improved greatly. That said however, the Carp have made a huge difference in our Lyngbya problem which has also been under control for the last two (2) years, with very few matting problems. We have been back on Stan Smith's recommendations since 2010 and with proper lake fertilization applications our food chain has been re-established, aquatic plants on the comeback, our frogs and shad at sustainable and reproductive levels, with fish population ratios back to normal, the results speak for themselves. The average Bass catch is back to 3 to 6 pounds with about 8 or 10 Bass caught in the past 12 months that were 10 pounds or larger, with the largest being 10.10, and another at These were our experiences with Tilapia use but given that each lake's eco-system is different in their own unique ways, I would recommend the use of a tenured Biologist such as Stan Smith to determine what your lake needs. Many Biologists recommend the use of Tilapia and Triploid Grass Carp, but based on our experiences with Tilapia, I will fight tooth-and-nail to make sure they never get reintroduced to our eco-system and make sure that the next Carp stocking is smaller than the last. If it will help, I monitor and maintain our lake's aquatic plants for invasive plants and the spraying of them when necessary and I will be glad to come back and check your aquatic plant status to see if there is anything I can recommend until you research your options. If I do, a boat will be needed for rake drags. This Texas A&M link can be very useful Should you have any questions, feel free to contact me. Thanks Lawrence Terry Lake Manager Lake Lydia, Inc. SPOA August 2016 Lake Report Update Page 6

7 There are, of course, other options to reduce the cost of tilapia introduction if that turns out to be a recommended and viable option. A SPOA resident provided us with the telephone contact for a local bait fish farmer, Mr. Richard Doss. Although Mr. Doss said that he no longer raises exotics like tilapia or grass carp, he has contacts in the East Texas area and suggested buying smaller fingerlings, raising them in floating cages until they are large enough to be released into the lake. He said several lakes have used this method to control costs. If this method was to be used, however, it would require someone to conduct daily feeding for about 45 days until the tilapia become large enough to release. Tilapias are mouth brooders and would likely miss one spawning cycle if this method were used. In summary, the purpose of this Lake Report is to explore options that are available to us and solicit your thoughts, comments and priorities regarding lake maintenance. Every lake is unique with its own ecosystem and issues. What works in one location may not be appropriate or effective for another. There is no easy or inexpensive solution to our lyngbya problem. SPOA-generated revenue this year has been allocated primarily to road maintenance, particularly because we were not able to conduct needed maintenance during At minimum, however, we believe we should reach out to Biologist Stan Smith of Tyler for professional review and input as suggested by Mr. Lawrence Terry. Sincerely, SPOA Board SPOA August 2016 Lake Report Update Page 7