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Orange Creek Basin Interagency Working Group MeetingApril 30, 2015Alachua County Environmental Protection DepartmentGainesville, FLMeeting SummaryAttendeesTiffany Busby, Wildwood Consulting for FDEPJim Couillard, Marion CountyJian Di, SJRWMDDan Dorosheff, FWCDoug Dycus, FDOTRobert Freese, SJRWMDSonny Hall, SJRWMDRyan Hamm, FWCBarbara Hatchitt, SJRWMD-ERPStephen (Steve) Hofstetter, ACEPDBruce Jaggers, FWCMark Kuhn, FDOTJames Link, ACPWPatrick McCord, FWCMary Paulic, FDEPDale Smith, SJRWMDAndrew Sutherland, SJRWMDIntroductionsSteve Hofstetter, Alachua County Environmental Protection Division (ACEPD) welcomed everyone to the Alachua County facility and everyone introduced themselves. Orange Lake Management Activities UpdateRyan Hamm, Florida Fish and Wildlife Conservation Commission (FWC), reported that since December 2014, the FWC has been working to maintain lake access at two boat ramps—one on the east side of the lake and one on the west side. The tussocks are being moved around the lake by winds, so they are usually crowded against one lake shore or the other, but not both. The FWC is continuing the effort to shred some of the tussocks at the boat ramp sites.The FWC has also been working on creating moat areas at three sites: Red Bird Island, Bird Island, and Grassy Point. The objective of these efforts is to create bird rookery areas. There was a fourth site that was not improved as winds blew out the tussocks and so intervention was unnecessary.Patrick McCord, FWC, reported that monitoring of bird usage of the three sites is underway. In March, some bird roosting was observed. In April, bird nesting (e.g., anhingas and green herons) was observed on Red Bird Island. Bird Island and Grassy Point have continued bird roosting, but no nesting has yet been documented. Ryan added that the FWC has also planned to shred about five acres of tussock at the Heagy Burry boat ramp. As part of the project, pre-project water quality data were collected. The FWC staff planned to start shredding today (April 30, 2015), but on April 29th, the wind blew about 200 acres of tussocks into the area. This has put the project into a holding pattern while they assess the situation.Bruce Jaggers, FWC, reported there are two issues with the project at the Heagy Burry boat ramp: the first issue is that their permit does not allow shredding of 200 acres of tussock that is now in the area; and the second issue is that shredding a lot more material would be a large increase in the scope of the project. Ryan added that now with around 1,000 acres of tussocks in Orange Lake, the winds blow them around and the frequently create problems. This has been a common situation in the last two to three years. Bruce stated that the lake stage is pretty high right how and water is currently flowing over the weir as a result of recent rains.Patrick commented that during the stakeholder meetings in December 2014, they discussed the on-going efforts in Essen Run. The FWC has now begun the last phase of the project to address 100 acres of tussocks that was partially held in place by willow trees and is therefore a considerable effort to remove. This last phase started on March 10th and is finishing now.Orange Creek BMAP UpdateMary Paulic, Florida Department of Environmental Protection (FDEP), reported that she is setting up technical discussions via conference calls related to the Orange Creek Basin Management Action Plan (BMAP). A call had been scheduled for May 5th, but several people have reported conflicts with the date, so it may be postponed. During these calls, Mary will be vetting ideas and getting more knowledgeable about the issues we face. She is also working on achieving more complete stakeholder representation, particularly from the small municipalities in the basin. Mary mentioned that the concept of doing allocations was discussed at the March 2015 meeting and we need to talk more about how that might work. FDEP needs to look at the nutrient sources to the lakes, especially for Lochloosa Lake, and maybe have some discussions about projects. Mary is also planning for the annual BMAP meeting that is scheduled for August 6, 2015. The technical discussions being scheduled related to the BMAP will not be identical to the Interagency Working Group meetings.Mary added that she met yesterday (April 29, 2015) with the Alachua County Department of Health, University of Florida (UF) and the Paynes Prairie State Park regarding Lake Wauberg. Mary is assessing what is happening out there and what sewage facilities exist. There is a large septic tank system at the UF site and also a septic system at the park. Mary noted that the Lake Wauberg total maximum daily load (TMDL) was adopted in 2003, so she is trying to assess the more current situation. Some of the lake conditions may be natural, especially since the lake bottom sits in the Hawthorn layer, which is a phosphorus source. However, there are increasing chlorophyll-a trends in recent years, so not all the changes can be related to sediment sources. FDEP is looking into conducting a phytoplankton analysis of the species in Lake Wauberg. The lake looked very green during their site visit yesterday. Mary noted that FDEP will continue to work on Lake Wauberg and potential restoration approaches.Mary added that there is a question about whether George’s Pond is connected to Orange Lake and if there are important sources around George’s Pond that are influencing Lake Wauberg. The watershed area defined for Lake Wauberg is quite small for such a large lake. Mary noted that she may need to follow up with Florida Department of Transportation (FDOT) about U.S. Highway 441 and the influence of the roadway on the basin. Doug Dycus, FDOT, responded that George’s Pond is connected to Lake Wauberg. Doug explained that George’s Pond drains south under the county road and then through a culvert under Highway 441. Mary replied that she would like to follow up on the details of this connection. Bruce noted that based on the FWC monitoring, there are often low dissolved oxygen (DO) levels in Orange Lake and asked whether those are being addressed by the BMAP. Mary replied that FDEP does want to see all the DO data loaded into the Storage and Retrieval (STORET) database so that the Department can see what is happening in the lake. FDEP collected some phytoplankton samples in December 2014 and Mary is waiting for the results to come back from the laboratory.Patrick commented that he often thinks of the lake as two systems—an open water system and the perimeter marsh. Over the last two years, the perimeter has been matted out and the lake’s water column has little to no exposure to air. In those areas where there are extensive mats, the DO gets very low, but it is erratic. When the wind shifts the mats around, higher DO concentrations may be observed, but then the concentrations often drop down again.Ryan noted that FWC stocked the lake with about 100,000 large-mouth bass last weekend. In the open water, they often measure DO levels of six to seven milligrams per liter (mg/L). Under the mats, the DO levels are often 0.5 mg/L or 0.0 mg/L. Jian Di, St. Johns River Water Management District (SJRWMD), asked how the fish stocking works under these conditions and if the FWC observes large fish mortality rates. Patrick responded that the FWC has not seen evidence of large fish mortality. There may be micro-refuges where the fish can survive. Ryan added that during the water quality sampling they observed DO levels under the tussocks of 0.5 mg/L; along the edges of the tussocks the DO concentrations were around 1.5 mg/L, and then it goes up from there. In the main part of the lake, DO levels are observed around 6.0 mg/L.Jian asked about measurements toward the bottom of the lake and whether the DO levels drop significantly at depth. He noted that surface DO levels tend to be higher. Patrick replied that they are trying to organize their data. At their tussock shredding sites and at the bird rookery sites, they are taking pre-project, during-project, and post-project water quality samples. It is usual to observe elevated DO levels during the shredding process due to the agitation taking place. However, there appears to be little effect afterwards. The FWC plans to go back quarterly to the same sites to see if DO conditions improve.Mary asked if there had been any follow up on the possibility of hiring UF to perform some water quality studies on different treatment methods. Patrick responded that they had planned to fund a demonstration project that involved herbicide and mechanical harvesting along with water quality sampling. However, there were some projects that were not conducted in this fiscal year that now have to be funded in the next fiscal year, and therefore there may not be enough remaining funds in the next fiscal year to support that project. The project is being reviewed now. Bruce commented that he thought the funding for the project had been eliminated. Patrick replied it was below the funding line but whether it gets funded or not will be based on the carry-over budget. Ryan added that UF has been contracted to assist with the Heagy Burry boat ramp tussock shredding project. UF collected the pre-project samples and is prepared to collect the during-project and post-project samples if the project can proceed after the additional tussock areas that blew in this week.Sonny Hall asked if anyone had tried burning the tussocks. Patrick replied that some burning is being considered but it requires special permits and special training of the staff to conduct. Sonny added that there might be some assistance from the SJRWMD staff that has expertise in controlled burning. Bruce noted that getting the permits for burning is the hardest part, especially due to the lake’s proximity to major roadways including Interstate 75, U.S. 401 and U.S. 301. Smoke interfering with roadway visibility is always an important concern. Patrick commented that we would need the peat soils to be wet in order to prevent fires as well. It is also possible that the soils could release nutrients. Patrick asked if anyone had studied that. Mary encouraged Patrick to keep talking to the FDEP about these issues and concerns.Ryan noted that the FWC has hired a contractor to help with the Orange Lake Management Plan and they are in the process of conducting individual stakeholder interviews. Another public meeting will likely be held in July 2015 which will also be the official start of the habitat management plan process.Agency UpdatesJian noted the he had emailed out some graphs of the lake stage data for everyone’s reference.Jim Couillard, Marion County, noted that the county has been working on road access improvements at the Heagy Burry boat ramp and parking area. Re-grading of the area is underway and should be completed in the next 30 to 45 days. Jim also noted that they have permits in place for an additional project to rebuild the dock and there is funding currently in the next fiscal year’s budget, so if the funding remains the project should begin in October Steve provided an Alachua County update and noted that the Plum Creek (Envision Alachua Sector Plan) application is not in and is expected in June 2015. Steve noted that the Florida Legislature has been considering a sector plan bill that would provide more limited review time for sector permits such as the Big Plum Creek application. Steve was unclear if the bill had passed before the Florida House adjourned under sine die or not. Steve noted that Alachua County has its own annexation process and another bill, if passed, would remove those local provisions. Steve also explained that the annexation rules are related to whether the proposed area of annexation is connected to the current boundary or not; the connection, however, can jump over a waterbody.Bruce asked if there had been community discussion on water and land in the area. Steve responded that Alachua County has an Environmental Protection Advisory Committee who provides guidance to the Board of County Commissioners. The Environmental Protection Advisory Committee has decided to host some workshops related to these issues. Tonight (April 30, 2015) there is a public workshop scheduled on water resources with a panel discussion on the challenges that Alachua County is facing. Doug stated that he did not have any updates from FDOT.Ryan asked Steve how the Environmental Protection Advisory Committee workshops are noticed. Steve responded that the main way they are noticed is via email. Steve added that he could forward the notices of future workshops to this group, in case they are interested. Sonny asked if these workshops are recorded. Steve responded that he wasn’t sure.Tentative Hydrogeology WorkshopMary stated that she had contacted some potential speakers including Harley Means (FGS) and Jeff Davis (SJRWMD), but her other workload had not enabled her to focus on completing the plans for the workshop. She asked for help from the other members. Someone asked what kind of help was needed. Mary responded that a meeting site needs to be secured, the speakers need to be contacted and confirmed for a date that works for all of them, and an agenda needs to be created. Sonny suggested that Sam Upchurch, SDI Global in Tampa, would be an excellent contact or a peer reviewer. Mr. Upchurch has done a lot of work in the Suwannee Basin. Sonny offered to provide Mary the contact information for Sam Upchurch. Bruce noted that the tentative date for the workshop was May 13th and at this point, that is too soon to allow adequate notice. Mary responded that the Silver Springs BMAP has been taking much of her time. Ryan offered to help Mary with the hydrogeology workshop planning and offered to talk to her on Tuesday, May 5th to coordinate efforts. Ryan added that Erich Marzolf (Suwannee River Water Management District) had given a very good, basic presentation on hydrogeology in another setting. Since it is a public workshop, we have to be careful about the level of technicality of the presentations and Erich’s was well-done for a non-technical audience. Mary noted that she is wondering whether the session should be a two-part series with some presentations and then with some field observations. Bruce noted that some of the minimum flows and levels (MFLs) items fit in too. Dale Smith, SJRWMD, noted that the U.S. Geological Survey (USGS) has a new publication available about the hydrogeology of the Southeastern United States, including Florida. Patrick added that it is likely that the public will bring up questions about the weir.MFLs in the Orange Creek BasinRobert Freese, SJRWMD, provided a PowerPoint presentation on the status of the MFLs. Robert reviewed the definitions of the MFLs and the statutory directives. Robert outlined the eight environmental values that are considered when setting MFLs, and particularly those related to lakes and recreational uses. Sonny added that SJRWMD is the only district that defined the environmental values being applied during the MFL process. In larger systems, the District’s contractors evaluated whether the MFL would be protective of these items. During the process of defining the values, SJRWMD conferred with Janet Llewellyn at FDEP. Robert continued to review his slides and noted that the MFL program started in the early 1990s. He showed a map that indicated where MFLs have already been established within the SJRMWD (red triangles) and whether they are underway (orange dots). One of their criteria they use for selecting where MFLs need to be established is in systems where there is strong connection to the Floridan aquifer. Therefore, you see that the MFL areas are in the central portion of the state where the geology provides strong aquifer connections and less in the northeastern part of the state where the aquifer is more isolated from the surface waters.Robert noted that arguably Newnans Lake has less of a direct connection to the Floridan aquifer than some of the other lakes in the area, but since it is part of the system, it was given a high priority for MFL development. Sonny stated that the Orange Lake system is an important regional resource, so the SJRWMD is working on all of the large lakes in the region. They had originally started work on these MFLs but the process was put on hold for a time and re-started again recently. Robert added that these lakes went on the MFL development list in 2013 and they are due in 2018.Robert continued that there are multiple levels of consideration and those are designed to protect the normal ecological functions of lakes that include both flooding and drying cycles. They look at historic events paired with return frequency. They look at hydrologic data for historic recurrences or at reference sites for frequency probabilities, when hydrologic data specific to the lake is lacking. This approach assumes that hydrology is the primary driver.Robert reviewed some examples of MFLs such as the Middle St. Johns River. This example is a river system so the levels are converted to flow. The Middle St. Johns River criteria considered flooding events as well as dewatering events. During dewatering events, they want to prevent the oxidation of organic soils and the dewatering of seasonal wetlands. Robert reviewed the hydrologic models used in the Middle Johns River example. Robert explained how the stages and exceedances are used to interpret at what levels the MFLs are being met. The stage differences help to determine the freeboard available. Robert noted that consumptive uses are evaluated with a regional ground water model. The model allows the prediction of impacts related to cumulative withdrawals. Sonny noted that fern irrigation operations often use direct surface waters for irrigation. The model helps to quantify how much surface water can be used before tripping the MFL.For the MFL process for the Orange Creek Basin lakes, the MFL process for Orange Lake is underway with a target completion date of April 2016. The SJRWMD is working on transects now for Lochloosa Lake with a target completion date of November 2016. The MFL process of Newnans Lake has not yet started and has a target completion date of April 2017.Jian asked what kinds of data the MFL effort is collecting. Robert responded that they collect soil, vegetation, and elevation data. Jian asked how often those data are collected. Robert responded that they usually collect those data one time and look, in particular, at the plant community distribution. Sonny added that the District staff collected data for the Upper St. Johns River over multiple years, but that approach is not common. For lakes, they often focus on one data collection effort. They may monitor the sites over time, but it is hard to tease out water withdrawal effects from the effects from climate and drought cycles. Soon, the SJRWMD will be giving a presentation to the FDEP staff about the wells being used for springs and lakes measurements. The SJRWMD performs a double-mass analysis. By looking at the cumulative spring flow and rainfall levels, they can look at the slope of the well elevation data and determine the anthropogenic effects on the water levels. Jian noted that they could use the slope from historic data as the baseline. Sonny concurred and added that it is a powerful tool. Patrick asked if the analysis of the vegetation along the transects is used as a benchmark. Robert responded that it is if they go back to look at the same transects later. For sand hill lakes where the vegetation isn’t stable, they use other tools. Andrew Sutherland, SJRWMD, added that they monitor some sites and compare the hydrology. Patrick stated that Orange Lake is dynamic and they need to account for woody encroachment and changes that occur through drought, therefore the agencies may need to coordinate. There has been an increase in woody shrub swamp from herbaceous marsh. The FWC has been managing vegetation in some places, and they don’t want to mess up your vegetative transects. Sonny responded that the SJRWMD would be okay if the areas were treated. They want to make sure the “tub” is filled to a high level at a certain frequency. It is possible that the levels may not be high as frequently but they want to get to those high levels often enough that there is no permanent encroachment of upland plant species.Patrick asked if it is possible to perceive the natural conditions versus those conditions that are being actively controlled through management. Robert responded that the encroachment of shrub swamps doesn’t affect the MFLs. Patrick asked about the possible impacts to organic soils. Robert replied that the soil survey indicated some organic soils in the area. However, in the surveying the SJRWMD has performed they have only found some mucky layers and not true organic soils. Lochloosa Lake and Newnans Lake have some organic soils, but not Orange Lake. Ryan asked how organic soils are defined. Robert responded that a true organic soil has at least eight inches of thickness of the organic layer and in Orange Lake; they are only finding a few inches of organic material in the soils. Patrick asked if peat is considered to be a histosol. Robert responded that, yes, but if you see floating mats and other floating materials, they are not considered to be soils. Patrick offered to help identify some sites where there might be some truly organic soils. There are “peat birds” that come up to the surface four to five feet thick sometimes in Orange Lake. Sonny noted that they rely primarily on the soil surveys, so more specific local knowledge is welcome.Orange Lake Weir IssuesSonny Hall, SJRWMD, provided a PowerPoint presentation giving a summary of Publication SJ-97-SP8, Water Management Alternatives: Effects on Lake Levels and Wetlands in the Orange Creek Basin. Sonny noted that Orange Lake has several problems including weirs that have stabilized water levels; excessive growth of nuisance aquatic plants; water quality degradation; increased accumulation of sediments; and declines in recreational fishing. Sonny explained that the SJRWMD completed a study in the late 1990s to evaluate the ecological efficacy of various water management strategies. There was also a Working Group in place at the time to discuss issues and to provide input. Bruce asked what made the Working Group stop meeting. Sonny replied that he wasn’t sure. There was a Section 120 hearing held and they did look at the various management options. There were some fish camps that wanted to manage the sink hole in the lake and that wasn’t a viable project. The main point of public interest was the decline in fishing. At some point, the Working Group stopped meeting.Barbara recalled that Marion County had applied for a permit to plug the sink hole in the lake, and the SJRWMD denied the permit. Bruce added that it isn’t really a single sink hole; it’s a complex of geologic structures. Therefore, plugging one sinkhole would likely have no effect because the water would travel through other structures. Bruce added that we definitely need to cover that item at the public workshop, so the public understands more about this. Sonny agreed that there are many sinkholes in the area and with certain tools you can hear the water running underground. A dye study was also done to define the 1,000 year capture zone for the Silver River. When dye was placed in Orange Lake, it showed up in wells south and southeast of Orange Lake near Reddick within six months, and so the connection was determined to be faster than previously thought. Dale added that UF has been studying the known fractures and how water flows as part of the Silver Springs Initiative.Sonny stated that the studies underway will provide better data. One of the main hurdles right now is the modelling because it is so complicated. Sonny reviewed the study objectives for the previous SJRWMD study of alternative surface water management strategies. Sonny also reviewed how the biohydrologic criteria are developed, noting that lake and wetland ecosystems require a range of surface water fluctuations. High, middle and low water levels are all important and water management options can increase or decrease the range of water level fluctuations.Sonny explained that five criteria were created that promote a range of water levels over time including infrequent highs, frequent highs, middle, frequent lows, and infrequent low water levels. The biohydrologic criterion each describes duration and a recurrence interval. The intervals were formulated by examining the physical and biological features of the wetlands. This approach is supported by scientific literature and SJRWMD research.Sonny provided the example of Newnans Lake and the surface water levels generated by the model called the Streamflow Synthesis and Reservoir Regulation?(SSARR) model. Sonny noted that the hydrologic modelling was performed by Price Robinson who will be retiring from the SJRWMD in May 2015. Price looked at the possible effects of removing the Orange Lake weir; overall it is expected to lower the water levels in the lake. Sonny noted that there had not been a lot of regeneration of trees because it was too wet. There was general agreement at the time that it would be good for the lake to remove the weir to better allow for periodic drying events. Overall, 23 different alternatives were defined including the existing conditions, a new weir, and a low flow notch in the weir with plugs. Ryan asked if the conditions were evaluated after the water reservation. Sonny replied that the alternatives were evaluated before the water reservations (Paynes Prairie) were defined. The water reservations were the next step. Sonny added that an option to plug Alachua Sink was not discussed at the time. Orange Lake and Lake Lochloosa were the main focus of the study.In the meantime, the low-flow notch in the Orange Lake weir was filled; it was never determined who filled the notch as it was not permitted. The study did look at different weir heights and sink hole management alternatives. The sink hole management wasn’t a good option because plugging the sink hole could open other holes elsewhere. Sonny added that the report itself has a lot of information on the model calibration that Price performed. Sonny showed an example of the existing condition versus removing the Orange Lake Weir. Ryan asked for clarification that the alternative to remove the Orange Lake weir was to remove the 160 foot long structure under the bridge. Sonny agreed that, yes, the weir removal alternative evaluated the removal of the entire wall, with lake levels subsequently dropping slightly. Sonny added that the bottom graph in his PowerPoint shows the change (the “delta”) between the two conditions. Steve asked if the model shows the pre-1993 conditions when there was no weir. Sonny responded that the model is calibrated using some data prior to 1993 and the weir. It is helpful that the land uses have not changed much since 1993. Dale added that it is confusing to people sometimes when the SJRWMD explains that they used rainfall records since the 1940s but we use current conditions in the model. Even though historic rainfall data are used to establish the highs and lows in rain, we are predicting future impacts so it is appropriate to use current conditions along with historic rainfall patterns.Mary asked what land use data were used—1990 or 1995. Sonny replied that the land use data were from around that time and it should say in the report exactly what year was used. Sonny added that the SSARR model was originally developed by the U.S. Army Corps of Engineers and since the time the Orange Lake model was developed, the Corps stopped using that model. Now, the SJRWMD uses the hydrologic simulation program-FORTRAN (HSPF) model as the model of choice. Sonny added that any land use changes through 2013 have been incorporated into their model. Sonny explained that most of the adopted MFLs have used the SSARR model, but it is tricky to convert them to a different model platform. It is possible that the SJRWMD will develop an HSPF model for those MFLs where there are significant changes in land use.Mark noted that folks want the weir removed in order for the tussocks to have a chance to exit the lake by flowing out downstream and asked if that is correct. Mark asked if anyone has tried to calculate the displacement volume of the tussocks and whether that is accounted for in the existing model. Dale responded that the displacement volume is not accounted for since the quantity of tussocks is so dynamic. The model is calibrated to the lake stage levels. Sonny showed the elevation-duration curves and that if the weir was removed, you would expect increase water discharges from Orange Lake. Sonny also reviewed a table of the water management alternatives and the fluctuation changes. Removal of the weir is only expected to make a three-tenths of a foot average reduction in lake levels, but overall the lake level would be expected to be lower under average rainfall conditions.Patrick asked if the elevation data are in National Geodetic Vertical Datum (NGVD) 29 units or North American Vertical Datum?(NAVD) 88 units. Sonny replied that they are in NGVD29 units, so that should be considered when reviewing the report and its data. Dale responded that all the older models are in NGD29 and need to be converted to NAVD88. The NAVD88 will be about a foot lower than NGVD29. Sonny showed a graph as well as a table describing the results of various alternatives. Sonny displayed a table showing the changes in acreages predicted as the result of the complete restoration of Paynes Prairie and the largest effect form that project would be higher water levels. By plugging the Orange Lake sink hole, the model predicted that the water levels would rise and flood out riparian wetlands which could increase the amount of tussocks created.Sonny showed a summary table that described the changes in the ranges of surface water levels and the advantages for Orange Lake and Lake Lochloosa. Jian asked if the data show a ten percent change in wetland acres over time. Sonny replied that, yes, it shows the change in the number of days at each level, on average. Mary provided a copy of Sonny’s summary table as a handout.Sonny noted that the full reports are available on request.Steve stated that he would archive copies of both PowerPoints and provide them to FWC and FDEP.Ryan noted that stakeholders are interested in raising the bridge of U.S. 301 so that the tussocks can move out of Orange Lake. Sonny noted that if a cross section could be provided of that alternative, it could be modelled. It was noted that there is also the potential flushing of organic sediments and how much those would flush out of Orange Lake. Raising the bridge would be a large project, but it is unclear if it would result in benefits to the lake.Dale commented that it would be possible to model the water level changes using the current model. To look at how the sediments might move, we would need to build a water quality model such as HSPF, which is not set up. Sonny noted that the railroad grade is also there and needs to be considered. Dale added that the HSPF model works on a grid system. For very detailed information, you would need a different hydrologic model which would also require a lot of data. Dale added that the HSPF model has a tool for “special actions.” Pete Sucsy (SJRWMD) could look at this possibility, but it would be a challenge to model.Andrew commented that if the purpose of the project is to remove tussocks, we should evaluate whether increasing the days with drier conditions (because of lower water levels) we should consider the effects on tussock creation. Sonny agreed that it is possible that removing the weir could be counter-productive if the drier conditions produce more tussocks. Sonny and Dale both agreed that it would be extremely difficult to model tussocks. Bruce noted that if the weir was removed or failed, what impacts would occur to the MFLs. Sonny replied that they would need to factor in the effects on hydrology. The MFLs might still be achievable with the removal of the weir because the difference to lake elevation was predicted to be small. Patrick noted that there is stakeholder perception that there were not always such high water levels and they want the water levels restored more like the way they remember. He asked if that can be modelled, especially since Camps Canal was dug prior to any data collection. Dale responded that the model could be used for that type of exercise; that is a lot of the work that Price performed. Dale added that if you knew what it looked like then, it could be modelled. You could look at the existing grade and with HSPF they use rating curves. You can use the rating curves to reflect more sheet flow instead of the canal flow if you are modelling pre-canal conditions, but you do need a sound basis for what you model.Patrick asked if it would be helpful to understand different scenarios. Dale replied that it is possible in the model to change land use back to the 1940s but before that, it’s fuzzy due to lack of data. Jian asked if there was not the Camps Creek Canal what the lake levels would be because Camp’s Canal diverts water to Paynes Prairie but also Paynes Prairie flows into Orange Lake. Ryan asked how you would calculate sheet flow that occurred from Paynes Prairie to Orange Lake. Sonny replied that the modelers think, historically, those flows were infrequent. Dale added that they think that Paynes Prairie was a sink for water, generally. Sonny noted that there is a water reservation for Paynes Prairie. The structure there is old and may not be able to close. Price looked at if the culverts were open then about 45 percent of the flow goes to Paynes Prairie and the rest goes downstream. Price assumed a 45%/55% split in flows (Paynes Prairie/downstream). Theoretically, they could close the culverts to prevent highway flooding. They started producing baseline conditions on Orange Lake with all the conditions the same as current except that the consumptive uses were eliminated to see what that looked like. Sonny noted that they used the same approach when they modelled the lakes in Clay County using the SSARR model and it showed that the consumptive uses are not the major driver of lake levels there. Sonny added that a separate consultant did his own modelling of the Clay County lakes and he came up with similar results.Bruce noted that there was an engineering report produced in the 1960s where weirs were recommended. Sonny responded that Price reviewed those reports. Bruce added that in the report, 18 fish camps were surveyed on their desired lake levels; there are now two or three fish camps on Orange Lake, so the number of fish camps has significantly declined since the time the survey was done. Steve asked about the possible impacts east of the weir if it was removed. Dale noted that the area is modelled all the way to the St. Johns River outfall, but those downstream effects of weir removal have not been evaluated, so that would need to be done to have those answers. Steve noted that the agencies need to be able to answer that question in order to recommend what to do with the weir.Steve added that the railroad may be a bigger issue than U.S. Highway 301. Mary asked if there had been any concerns raised from the residents downstream of the weir. Steve responded that there are some blueberry farms and other residents there, but they may not be engaged in these discussions and know that there is the possibility that they might be affected. Mary noted that there are other stakeholders besides the fish camps. Sonny stated that the District is willing to consider the question about downstream impacts and moving flows downstream. Dale added that flooding is an important question. Tiffany Busby (Wildwood Consulting) asked how quickly that question could be answered through additional modeling of the downstream areas. Dale responded that the SJRWMD could use the HSPF model to look at changes and to see the initial effects. Sonny added that there is a lot of data that still holds up well because there have not been a lot of land use changes in that area. Steve asked what the next water control structure is downstream. Dale responded that the Rodman reservoir and its dam is the next structure.There was discussion about ecotourism and the shallowness of the waters.Mary noted that there is a Lochloosa Lake TMDL as well which is based on the HSPF model developed by SJRWMD. The TMDL model has a water quality component. Dale added that the SJRWMD model could likely be extended to Lochloosa Lake because it is a good base and has been peer reviewed.Mary noted the Paynes Prairie sheet flow restoration project and the development of a level II water quality-based effluent limit (WQBEL). The Department has not seen the results of the WQBEL yet, but it is supposed to provide evidence that the TMDL for Alachua Sink will be met. Steve noted that as a result of the Paynes Prairie project, there should be more water being discharged at the south end of Paynes Prairie. Sonny noted that the area looks great now, especially the vegetation. Ryan noted that aerial spraying has been conducted.Sonny offered to come back to another meeting to present some of this information in more detail or to present other topics of interest. He noted that the SJRWMD is using the models to tease apart the water uses impacts versus the climate effects on water levels. Steve asked if the report still reflects a reasonable assessment. Sonny replied that the analyses are still viable and now there will be another tool as well with a longer period of record with the revised ground water model. Dale added that there is no direct link with the ground water model but their model will take the ground water model’s outputs and use those data as well as hind cast; there will be a constant comparison between the two models. Sonny noted that their tools keep getting better.Ryan asked when the new analyses will be available. Dale responded that the MFL work will proceed as scheduled, but additional work to answer management questions would need to be requested from Sonny’s group and accounted for in their DAPTIVE management software for scheduling staff time. There was discussion of the work order process.Tiffany asked for clarification on which model was being extended now; it sounded like the environmental fluid dynamics code (EFDC) hydrodynamic model was the one being extended by Pete Sucsy. Dale confirmed the EFDC model is the one being extended into additional basins and the HSPF model is already set up for the Orange Creek Basin, except for the Paynes Prairie area.Patrick asked if there is interest in the impacts from the Upper Ocklawaha and Moss Bluff. Patrick also asked if there is any regulation of those discharges/ Sonny responded that the SJRWMD will probably do an MFL for that area and that there is an existing HSPF model for that area. Patrick noted that there has been loss of habitat along the river and it may be due to hydrology. Dale commented that there are EFDC models for the Ocklawaha and the St. Johns River, but they run as separate modules.Mary noted that the next Orange Creek BMAP meeting is scheduled for June 4th and she will consider what information to present related to these discussions and may follow up with both speakers and group members. Sonny responded that he will be out of the office May 21-27, but is around in early June.Dale showed a graph of the historical record and a red line that showed the well levels. The graph demonstrates that Orange Lake and the Floridan aquifer are highly connected. The SJRWMD is doing a better job at linking the two during their MFL work than they were able to do during the water supply impact study (WSIS) when fewer tools were available.Sonny commented that they are going coast to coast on the ground water model so the tools are getting better. Those models can also evaluate the wells that are going deeper to pump water. Mary commented on the Orange Lake hydrograph and that in the last 20 to 25 years there has been drier conditions than historically. Overall, the water trend is going down and they are seeing similar trends in the Silver Springs analyses.Sonny offered to send the graph from the Atlantic Multidecadal Oscillation (AMO) climate model to Mary, so it could be shared with the group. Sonny also offered to share some National Geographic articles from 2005 and 2006 about storm patterns; these show the contrast in tropical weather. The next meeting of the Orange Creek Basin Interagency Working Group was targeted for early August. Tiffany noted that the annual BMAP meeting for Orange Creek is scheduled for the afternoon of August 6th, so a time near (but not overlapping) to that date would minimize travel for Mary coming from Tallahassee. It was suggested that Richard Hamann could provide some good input at the discussions. Tiffany and Steve offered to coordinate on the production of the meeting notes. Patrick asked about possible failure of the weir and follow up. Steve noted that it would be unlikely the weir could be actively removed before understanding better what the downstream impacts might be. Sonny commented that the model will be ready in the next year. Tiffany noted that a service request is still necessary to schedule District staff time to address some of these questions. Sonny responded that Mary, as an FDEP representative, could make a service request. There was discussion about the lead agency for the weir since the previous lead agency no longer exists. AdjournmentThe meeting adjourned at 12:44 PM.Action ItemsDoug explained that George’s Pond drains south under the county road and then through a culvert under Highway 441 to Lake Wauberg. Mary replied that she would like to follow up on the details of this connection. (Completed--Material was forwarded to Mary.)Steve offered to forward the notices of future Alachua County Environmental Protection Advisory Committee public workshops to this group, in case they are interested. (Completed—the April 2015 workshop information was forwarded. Future meeting information can be found at )Sonny offered to provide Mary the contact information for Sam Upchurch. (Completed.)Ryan offered to help Mary with the hydrogeology workshop planning and offered to talk to her on Tuesday, May 5th to coordinate efforts.Patrick offered to help identify some Orange Lake sites for Robert where there might be some truly organic soils.Steve stated that he would archive copies of both PowerPoints and provide them to FWC and FDEP. (Completed.)Sonny offered to send the graph from the Atlantic Multidecadal Oscillation (AMO) climate model to Mary, so it could be shared with the group. Sonny also offered to share some National Geographic articles from 2005 and 2006 about storm patterns; these show the contrast in tropical weather. (Partially completed--Received from Sonny.)Mary stated that the next Orange Creek BMAP meeting is scheduled for June 4th; she will consider what information to present related to these discussions and may follow up with both speakers and group members. Sonny responded that he will be out of the office May 21-27, but is around in early June.Tiffany and Steve--Coordinate on the production of the meeting notes. ................
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