INTRODUCTION

The 1993 legislature was being pressured by Governor Chiles to destroy Rodman Reservoir in order to restore the lower Ocklawaha River. The legislature felt there was too much unknown about the Rodman environment and Rodman's economic impact on the State of Florida to arbitrarily destroy the reservoir until many questions were answered. They reserved the right to make a final decision on Rodman at a later date and allocated $900,000 for the environmental and economic study of Rodman Reservoir. The Florida Department of Environmental protection (DEP) was given the job of performing the studies. They in turn, contracted with the SJRWMD to conduct the environmental portion of the studies.

The purpose of the studies was NOT to make a decision on Rodman's fate, but to gather information. The SJRWMD was directed to address four possible scenarios. The official title was "Environmental Studies Concerning Four Alternatives for Rodman Reservoir and the Lower Ocklawaha River" (commonly referred to as the "1994 studies"). The four alternatives were:

Complete restoration was defined to be a condition where everything was put back as near as possible to the way it was before construction began. Partial restoration would only breech the dam and allow the river to return to its original channel with minimal work necessary to achieve this goal. Total retention would change nothing, while partial retention would lower the water level from a nominal 18 feet to a lesser value. The two water level values investigated were 14 feet and 12 feet.

The study as released by the SJRWMD was big and wordy. It contained twenty volumes and when stacked one on top of the other, the stack was over a foot high. We have attempted to write a short synopsis of each chapter without omitting anything important or altering the content. If any opinions are added the word (COMMENT) appears prior to the addition.

There are 20 volumes in the study. Volume 1 is the summary and the information presented here is from this summary.

(COMMENT): The first 12 volumes describe, after 27 years of existence, a healthy lake, low in toxicity and sediment. The only problem is excessive aquatic plant growth. Excessive plant growth control is available through periodic draw downs at no cost, see volume 16. Volumes 13 through 20 deal with the rest of Rodman's environment, the "critters" that live there and what might happen under the four different scenarios.

RIVER TRANSECT SURVEYING

Maps of 35 cross sections were prepared and submitted as the final products of this study. Due to the nature of the study, no written report was required, nor were impacts of the four alternatives considered

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VOLUME 3:

BATHYMETRIC AND SEDIMENT THICKNESS MAPPING

The old channel of the Ocklawaha River and the dredged channel of the Barge Canal are the prominent features on the depth maps; minor features are the old channels of tributaries to the Ocklawaha River, such as Orange Creek, Deep Creek, and Blue Springs Run. The 5,980 acres of the reservoir studied within the two zones at the normal elevation of 18 ft. had an average depth of approximately 8.4 ft., with a maximum depth of 31 ft., and contained about 16.4 billion gallons. A 50 percent removal of water would mean an elevation drop in the reservoir surface of 4.7 ft., while a 1 ft. drop in elevation would decrease the surface area by 4.7 percent and volume by 11.4 percent.

Soft sediments cover about 5,136 acres of the reservoir bottom (85.9 percent) with 844 acres having no measurable soft sediment. Where soft sediment existed, it averaged about 1 ft. thick, with an estimated volume of 240 million cubic feet. About 43 percent of the reservoir has sediments over 1 ft. thick, while only 3.6 percent of the bottom has sediments over 2 ft. thick.

(comment) Considering the richness of the environment, these sediment measurements after 27 years of existence indicate Rodman has many years of life to live before sediment build-up becomes a problem.

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VOLUME 4:

ANALYSES OF SOME SEDIMENTARY PROPERTIES AND ERODIBILITY

CHARACTERISTICS OF BOTTOM SEDIMENTS

The surficial bottom sediment is composed of gray to dark gray lumpy or fluffy masses of organic matter and well sorted sand. The organic matter decreases with depth below the surface of the bottom such that, at 1meter into the bottom, there is almost no organic matter. The material is layered so that the grain size increases from the surface of the bottom to the bottom of the 1m core samples. The pore fluids are slightly acidic.

The sediments are highly erodible. Critical shear stress or susceptibility to erosion is measured in units of pressure, (pounds per square inch or metric Pascals (Pa). The critical shear stress for the samples was on the order of 0.1 Pa.( clay's shear is 0.6 to 1.0 Pa. while sand's is 10.0 Pa.) The higher the critical shear stress value, the lower the susceptibility to erosion. The small grain-sized material in the upper portion of the core samples is more susceptible to erosion then the larger material near the bottom. Therefore, the top 1 ft. of the material is most susceptible to erosion. When erosion occurs , sorting also occurs and the organic materials at the surface of the reservoir would be first to erode.

This study pertains only to river restoration

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VOLUME 5:

The sediment yield analysis indicates that the erosion rates are within the tolerance limits for maintaining the top soil layer, that is, the potential for soil erosion is low. The mild slopes and existing land uses (forest, range land and swamps) provide good land cover that further reduces the possibility of soil erosion. Modeling results of sediment transport following dam breach indicated that total accumulated sediment outflows would be higher then inflows. Disposition usually occurs immediately downstream of a scour hole. The analysis indicated that sediments probably would deposit in the flood plain of the lower Ocklawaha and St. John's within 7 hours.

Based on the above findings, the following recommendations for the full and partial restoration alternatives are:

1. To maintain tributary inflows into the natural channel, selected sections of the existing barge canal should be filled to divert water flow to the river and not the canal.

2. The down draw of the reservoir should be implemented over several years to assure that vegetation on the river banks has adequate time to establish.

This study pertains only to the restoration alternatives

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VOLUME 6:

ESTIMATES OF SEDIMENT RE-SUSPENSION DUE TO WIND

Re-suspension of sediments in the floodplain of the reservoir are governed by wind waves. Because of the restricted fetch of the reservoir and the shallow depth, a fairly high wind speed is required to initiate re-suspension of sediments. The critical wind speeds in the floodplain are 15, 23, and 30 mph for reservoir depths of 0.5, 1.5 and 3.5meters (m) respectively. The minimum critical wind speed required to initiate re-suspension for all reservoir depths above 0.5m (1.6 ft.) is 15 mph, which is fairly high, probably occurring less than 30% of the time.

At mean depth of 2.5m (8 ft.), a wind speed of 25 mph is required to produce significant re-suspension. Because of fetch conditions, the shallow areas of the eastern portion of the reservoir are most susceptible to sediment re-suspension, especially in the presence of westerly wind. Re-suspension potential-in the channel is less than in the shallows

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VOLUME 7:

SEDIMENT CHARACTERISTICS, TOXIC ANALYSIS, AND SEEDBACK

The sediment evaluation indicated the accumulated sediments were high in water content (above 80 % by weight), were high in volatile solids (37% of the solids), and had densities only slightly greater than water (specific gravity of 1.16). The thickness of these sediments averaged about 1 ft. The sediments in the swamp and pool zones were similar; however the total organic carbon content was higher in the pool. The mean dry weight of the organic carbon in the swamp was 21.8 grams per kilogram, whereas in the pool, total organic carbon was 27.5 grams per kilogram ( 26% higher). The overall mean dry weight of Kijeldahl nitrogen and phosphorus was 13.3 and 0.8 grams per kilogram respectively.

A conservative, worst case scenario was developed in which the metals in 10% of the sediments were released by a severe storm. The analysis showed none of the parameters would exceed acute aquatic toxicity thresholds; only lead and silver would exceed Florida Class III water quality standards and then only slightly. In addition, current recommendations are to cease drawdown during storms. No reservoir water would be discharged and downstream waters would not be impacted. The concentrations of the various metals were compared with criteria established by State and Federal agencies, and did not exceed any established guidelines for any of the metals. Therefore, these comparisons indicate a minimal risk from toxic metals.

Sediment samples were kept in a moist condition for 124 days to enhance germination and growth. The majority of the seedlings that emerged were AQUATIC WEEDS ,primarily hydrilla and water lettuce. Several unidentified sedges and a monocot were transplanted to large containers and are being grown for taxonomis identification. NO TREE SPECIES WERE FOUND OR IDENTIFIED.

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VOLUME 8:

RODMAN FLOODPLAIN CHARACTERISTICS

Rodman contains about 8,500 acres. About 1/4 of the total area of the reservoir was cleared with a tree crusher. Clearing and grubbing (stump and root removal) was conducted on about 1/20 of the area along the canal route. A distance of 55 to 110 ft. on either side of the canal was cleared but not grubbed for a total width cleared of 400 ft. The total area cleared and cleaned up within the reservoir (excluding that done along the canal) was 3,400 acres (40% of the area). Where clearing was not performed, timber was left standing ,mostly on either side of the canal, but not necessarily in continuous stands. About 1,900 acres (1/5) of the forested area was left. Portions of the shore line, the river channel, and the proposed boat trail were cleared and snagged. An effort was made to identify spoil banks. Spoil-like features identified from aerial photographs include the canal berm on either side of the canal; the berm extends from the point where the canal enters the reservoir to just west of Kenwood. Dredging was halted just west of Kenwood. Another feature seen on the maps are berm-like mounds from just south of Orange Springs to Payne's Landing. These are dikes, constructed to allow heavy equipment to operate. This area was cleared and grubbed but not dredged. There are 7 other features that extend laterally from the dikes, eastward toward the river channel and westward toward the shore. They are drainage ditches. Submerged roads were hard to locate. The most notable were the Orange Springs ferry crossing road and southern tip of the Kenwood road. High Resolution Bathymetric data was collected to characterize cross sections of the river channel. The bottom ranged from 14 to 25 ft. deep relative to the normal reservoir depth of 18 ft. Channel widths ranged from 110 to 260 ft. and sediment thickness in the channel from 0 to 5.2 ft. although typically less than 2 ft.

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VOLUME 9:

SEDIMENT LOADING OF THE OCKLAWAHA RIVER BELOW RODMAN DAM

Under the retention alternatives, it is expected that the primary cause of sediment transport will be movement of river channel sediments during 25 year or stronger storms or re-suspension of sediments during strong winds. Strong winds would result in less than 10% of the sediments being transported out of the reservoir.

Under the restoration alternatives, it is expected sediments in the river channel will be transported downstream under normal river flow velocities. Re-suspension of sediments during the restoration down draw would not be expected to occur except during strong winds. Bottom velocities during calm periods are not expected to be sufficient to cause bed erosion.

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VOLUME 10:

HYDRAULIC AND HYDROLOGIC EVALUATIONS OF VARIOUS ALTERNATIVES

The 60-year average discharges obtained by computer simulation for Rodman dam varied from 1,674 cubic feet per second (cfs) for full retention to 1,736 cfs for full restoration. These values closely agree with the 47-year average discharge of 1,706 cfs. The following conclusions can be made:

1. Full retention allows 3.6% less flow than full restoration, with 3.1% and 2.5% for partial retention. The reduction in flow can be attributed to evaporation loss.
2. The median discharges for the retention alternatives do not differ greatly from full restoration, but the low flows and the high flows vary by a wide margin. This variation is caused by regulation of flows to maintain the reservoir at a constant level and indicates that the reservoir does not act as a flood control structure.
3. Discharges for major floods would be similar for all retention alternatives. Therefore, flooding below the dam would be the same with or without the dam.

Conclusions concerning the length of the river under various retention alternatives.

As the pool elevation is reduced the effect of the dam becomes less pronounced over a stretch of river, that is, the depth of water above the full restoration condition decreases.

Under existing conditions, biological observations indicate trees and some vegetation begin to show signs of significant stress (SS) at a distance of 3.9 miles downstream from Eureka Dam and no stress (NS) at a distance of 1.2 miles. Stress is the lack of good health caused by persistent flooding. Starting from Eureka dam, trees exhibit more stress as one moves downstream. Stress submergence depths are; 0.3 feet for NS and 1.8 feet for SS. These submergence depths were used to establish the points of NS and SS along the river for the alternatives using the backwater profiles. River restoration lengths were based on the location of the NS and SS points. The floodplain forest between the NS and SS points is considered partially stressed

1. The lengths of the river which are expected to be fully restored for partial retention are:

2. The partial retention alternative with a 14 ft. pool would offer optimal restoration benefits. The incremental lengths restored with further pool elevation reduction would be relative low.

3. The partial retention alternatives also contribute to converting large areas of SS areas into partially stressed areas. The total length of the river under partial and NS conditions would increase from 2 2/3 miles under full retention to 7.9 and 9.7 miles under partial retention alternatives of 14 and 12 ft. pool elevations respectively. Before construction of Rodman dam a 3,500 to 5,000 ft.-wide floodplain existed from Orange creek to the dam, therefore a large area upstream of the dam was already flooded. This study evaluated the total areas and depths of flooding between Rodman and Eureka dams and the areas that would be restored. Conclusions:

4. Between Rodman and Orange creek the flooded area with a depth greater than 6 ft. =

18 ft. pool - 4,240 acres.

14 ft. pool - 2,290 acres.

restoration - 380 acres.

As the pool elevation is reduced, the area of river restored increases at a greater rate up to a 14 ft. pool and then the incremental benefits with each foot of reduction in pool elevation become less. The partial retention alternative with a 14 ft. pool offers optimal benefits with respect to area restored.

Long term runs using the sediment transport model showed some inorganic (sand) buildup in the river channel midway between Orange creek and Eureka with full retention, but no unusual problems are anticipated. For partial retention, sand buildup shifts more downstream with each drop in pool elevation. For a 14 ft. pool, sand buildup is concentrated 2 miles upstream and downstream of Orange creek. No unusual sedimentation problems are anticipated.

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VOLUME 11:

SURFACE WATER QUALITY AND ALTERNATIVES ANALYSIS

Dissolved oxygen (DO) is the most important water quality parameter studied because it (1) indicates the overall health of the water; (2) fish rely on DO for survival, and (3) historically, there have been problems with low DO concentrations in the reservoir. The class III standard for DO in fresh water is "not less than 5 mg/L. The frequency of DO concentrations less then 5mg/L for the following zones were:

The median values for dissolved nitrate + nitrite decreased from an average 0.825 mg/L just downstream of the Silver River to 0.077 mg/L downstream of Rodman dam. This represents a 90% reduction in nitrate + nitrite. It is apparent that the reservoir's aquatic weeds are acting as a nutrient scrubber. Dissolved phosphorus concentrations also decrease as one moves downstream, but to a lesser degree from 0.42 mg/L to 0.013 mg/L ( a 66% decrease).

Concerning historic trends of the parameters examined, only nitrate + nitrite exhibited a trend. Upstream of Eureka dam and in the swamp zone of the reservoir, the trend was toward increasing concentrations, while downstream of Rodman dam the trend was toward decreasing concentrations.

The results of the QUAL2E model indicated that no restoration alternative will have significant effects on DO in the river because this zone will experience few hydrologic changes. However, in the swamp and pool zones restoration alternatives tend to increase the DO concentrations because of higher flow velocities, thus a higher rate of re-aeration. DO is highest in all zones under full river restoration.

Using a mass balance approach and knowing the concentrations of nutrients and flows into and out of the reservoir, the amount of nutrients lost to the reservoir living organisms and sediments were calculated. Given that 341 kg/Day of dissolved nitrate + nitrite and 46 kg/Day of phosphorus go through Rodman dam, it is determined that 2,405 kg/D of nitrate + nitrite and 82 kg/D of dissolved phosphorus are lost to the reservoir. Assuming partial retention and full restoration represent 57 and 0 % of total retention nutrient removal capacity, the impact for each of these alternatives was calculated:

An estimate was made on water quality resulting from erosion of soft sediments in the inundated river channel if river hydrology was restored. In a worse case scenario, all the soft sediments would be eroded over a 2-month period and all trapped nutrients released. With an average river discharge of 1,300 cfs, total suspended solids would increase 353 mg/L and total Kjeldahl nitrogen would increase 4.14 mg/L (a 10 fold increase). The re-suspension of phosphorus would increase the concentration to 0.23 mg/L for a 2 month period (a 12 fold increase). These increases are temporary. Nutrients would not necessarily be immediately available to plants.

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VOLUME 12:

THE IMPACT OF THE DRAWDOWNS OF RODMAN RESERVOIR ON THE SURFICIAL AND THE FLORIDA AQUIFERS (Wells)

All three methods used indicate there would be no significant effects of the Florida aquifer by the drawdown alternatives. However the MODFLOW model and convolution methods demonstrated the potential for effects to water table elevations in the surficial aquifer. These findings are based on limited data and simple analytical approaches. (comment; THEY GUESSED) To obtain more accurate predictions, a surficial aquifer monitoring and data collection program would have to be implemented. Once the required data are available, a more sophisticated ground water model could be constructed to more adequately predict the relationship between reservoir stage and water levels in the surficial aquifer. However, it is likely that the cost to replace the approximately 9 surficial aquifer wells in the Rodman reservoir area would be less than the cost to obtain more accurate predictions.

(COMMENT: They didn't even try! There are a lot more than 9 surficial aquifer wells in the area. The south bluff of the pool has about 200 parcels of private property within 1/4 mile of the lake, many of them with wells around 80 to 90 feet deep, that's about the same as the height from the lake's surface to the top of the bluff. Almost all of these wells would be affected and many would require re-drilling.)

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VOLUME 13:

CURRENT STATUS OF THE BLUENOSE SHINER AND TESSELLATED DARTER

No blue nosed shiners were collected at any of the test sites. Four specimens of the southern tessellated darter were collected during two visits to Orange creek at the SR 315 site. The results of this sample study are entirely consistent with previous systematic sampling in the river system. Restoration of the river hydrology through river restoration could potentially benefit these two species by increasing the availability of suitable habitat. It was suggested that a reintroduction program for the bluenose shiner might be necessary even if the river were restored.

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VOLUME 14:

OCKLAWAHA RIVER MIGRATORY FISH ASSESSMENT

No migratory shad, sturgeon, striped bass, or adult eels were collected from the river (one immature eel was collected). Forty nine striped bass were collected from the barge canal. 7 channel catfish were collected above the dam and 1 below. 7 channel catfish were collected in the barge cannel. The presence of striped mullet, striped bass and channel catfish above the dam indicates that some migratory fish are passing through the lock. Gizzard shad were the most abundant species taken in the sampling, being more abundant immediately below the dam and in the barge canal. The numbers below the dam appear to be due to the species normal movement toward swift water.

Commercial fishermen revealed that striped bass were common to abundant in the Ocklawaha up to Moss Bluff Dam, while anadromous shad were common but did not spawn in the river. Adult American eel were historically more abundant, but have undergone a decline in the river and throughout the St. Johns River. These observations support the historical information on migratory fish usage of the river. It appears that Rodman Dam poses a barrier to the spread of a variety of migratory fish.

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VOLUME 15:

FISH POPULATIONS IN RODMAN AND THE LOWER OCKLAWAHA RIVER

Fish populations in the lake and river were described using data collected during l992 to l994. These data revealed 42 species from 18 families. Dominate species in each area were:

Historical data for the river and lake produced a list of 69 species from 22 families. Several species have not been recorded from the reservoir since 1971, including such rare species as dusky and blue nosed shiners, southern tessalated darter and snail bullhead. This is probably due to habitat change from a river to a lake.

There have been shifts in abundance of some species since the creation of the reservoir. From 1968 to 1985, seven game fish, including largemouth bass, compromised 66.7% of the lake fish. From 1986 to 1994 this group compromised 16.2%. Analysis of the Ocklawaha River and the river zone of the lake revealed few changes among the time periods. Total lake biomass (weight per unit of area) was quite similar from 1968 until l985, averaging about 124 kilograms per hectare (kg/ha). From l986 to l994 it increased to 151.9 kg/ha. This increase was the result of proliferation of non-game fish, game fish levels remained uniform. Swamp biomass decreased from 138.5 kg/ha in 1968 to 99.4 kg/ha in 1994 and is now dominated by red ear sunfish.

Two major fish kills occurred in Rodman; in August l985, an estimated 8.5 million fish died, and in Oct. 1988 an estimated 2.5 million. Both kills occurred when dissolved oxygen levels dropped below 1 part/million. Decomposition of excess organic matter from surrounding landscape plus low flow and high turbidity were thought responsible.

If the reservoir is maintained in its present state, future fish kills are likely. Under "full retention" the reservoir should be managed for sport fishing. A sound management system should address the causes of low oxygen. Management strategies should include mechanical weed control, water level manipulation, and monitoring. A partial retention scenario involving a 17% reduction of surface area would not affect a significant change in assemblage patterns. In a restored river , many species now living in the lake would decrease in abundance while others would increase. Fish diversity would increase. Fish densities (numbers and biomass) would be lower in a restored river than in a retained reservoir.

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VOLUME 16:

AQUATIC PLANTS OF RODMAN RESERVOIR, l969-1994

50 species of aquatic plants, covering 60% of Rodman Reservoir ,have been recorded between l982 and 1994. The nonnative, highly invasive plants, water hyacinth, water lettuce, and hydrilla are the most intensively managed species. The ability to conduct drawdowns of the reservoir has been an important tool in weed management. The drawdowns that occurred have demonstrated, in combination with other aquatic plant managing techniques, control of these plants can be achieved while at the same time enhancing fish and wildlife habitat. The average annual cost to manage unwanted weeds for the past 25 years has been about $31,000, whereas the 22 year average drops to $14,000.

Of the four alternatives, weed management under partial retention will be the least advantageous and most demanding. A large part of the reservoir will likely be inaccessible to plant control crews. The full retention alternative will only be successful if regular drawdowns are incorporated into the plan. The cost of managing the understudy plants, during the restoration alternatives, until a mature floodplain forest canopy develops is likely to be SUBSTANTIAL.

(comment) It was determined that the "Partial Retention" scenario would be unworkable because there would not be enough water depth remaining even with a 14 foot water level to have an effective plant control drawdown and that plant control would be practically impossible.

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VOLUME 17:

FOREST SUCCESSION IN RODMAN RESERVOIR DURING RESTORATION

To provide predictions of floodplain forest successional stages, computer models using different planting scenarios with output time periods of 0, 10, 20, 50, 100, and 200 years were produced. Nineteen species of trees that produce dominant and subdominant canopy (greater the 10 inches diameter at breast height, DBH) and under story species (less than 10" DBH) were used. 267 simulations were run.

In locations that were constantly flooded, no new trees started, only existing trees that could tolerate flooding survived. Trees became fewer and larger over time as the forest matured.

After 200 years it appeared that planting scenarios did not alter the species dominating the area. No new seedlings appeared in flooded areas even with seed disbursal. In these areas, forestation could only result from planting water tolerant saplings.

In all scenarios where trees existed, the community type was floodplain swamp which was dominated by cypress, tupelo, popash, ash and maple. An alternate community type possible would be hydric hammack, characterized by the dominance of laural oak, water oak, sable palm, ironwood elm, and hackberry. Although these species occurred occasionally, they were not sufficient to reclassify the community type.

(COMMENT: If you visit Silver Springs, they will tell you bald cypress grows at a rate of 1 1/4 inch per 47 years. Probably, this is a little slow. Our research indicates a growth rate of closer to 1/10 inch per year. The 10" cypress trees talked about would take 376 years to grow using the Silver Springs figure or 100 years using ours. In any event, a canopy would not develop for at least 100 years.

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VOLUME 18:

THREATENED AND ENDANGERED SPECIES

PLANTS - Only three of the 25 subject plants were found: CHAEMACYPARIS THYOIDES, BUCKTHORN, AND ARNOGLOSSUM DIVERSIFOLOUM in the swamp forest along deep creek. Buckthorn was also found in the swamp forest of Rodman and downstream of Eureka dam but upstream of the Rodman backwater.

ROUND TAILED MUSKRATS - 72 round tailed muskrat houses were found in the reservoir. 14 of the 20 houses examined contained fresh green vegetation, indicating they had been recently used.

MANATEES - Within the past few years manatees have been observed in the Rodman Reservoir, the Ocklawaha River, and the Silver River. Based on state records, from 1976 to 1991, seven manatees were crushed or drowned at Buckman lock and Rodman dam. Devices have been added to the lock and dam to prevent such accidents.

BLACK BEARS -Black bears are able to move to and from the Ocala National Forest by going around the reservoir.

FLA. PANTHERS - The Ocala National Forest and Ocala river area are not considered potential panther reintroduction areas by the Florida game and Fresh Water Commission due to the density of human development.

BIRDS - Twelve species of birds occurring commonly in the study area include Limpkin, Little Blue Heron, Snowy Egret, Tricolor Heron, White Ibis and Bald Eagle.

FISH - Southern tessellated darters were found only in Orange Creek.

REPTILES -American alligators use the Ocklawaha River, but more are found in the reservoir. Eastern indigo snakes occur in the Ocala N.F. and the river floodplain provides suitable habitat for them. The Ocala River drainage in Putnam County appears to be an important area for the spotted turtle. The natural range of the Sewanee cooter is rivers , springs and associated impoundments that drain into the Gulf of Mexico. Sewanee cooters are in Rodman Reservoir, the Ocklawaha River and the Silver River.

Under the restoration alternatives the dam will be removed or breached and the river floodplain swamp eventually restored. Habitat for species inhabiting floodplain swamp forests will increase as marsh and aquatic habitats within the reservoir are converted to shrub swamp and eventually into floodplain swamp. A plant that will benefit is buckthorn. Several springs that existed between Eureka and Rodman Dams may be restored. It is possible that the area around the restored springs could support some of the species associated with atlantic white cedar swamp community similar to those along Deep Creek. Habitat for eastern indigo snakes would be increased. The presence of manatee bones in the Ocklawaha River support the theory----- that a restored Ocklawaha might provide suitable habitat for manatees. (Comment - Manatees now utilize Rodman. If they wanted to go upstream into the Ocklawaha River, they could.) Swamp forest provides excellent habitat for black bears, restoration of the hardwood swamps would increase their habitat. (Comment - The FWC has stated only enough bear habitat would be created to accommodate two black bears.) Restoration of the river, small creeks, and springs may increase suitable habitat for the southern tessellated darter (Comment - only if artificially introduced), the bluenose shiner and the spotted turtle. Negative effects of this alternative would be felt by round tailed muskrats and some bird species. As marsh is converted into shrub swamp, round tailed muskrats would decline and eventually be lost to the area. Birds species that would likely decline include Limpkins, Little Blue Herons, Snowy Egrets, Tricolor Herons. White ibis, and Bald Eagle. Although alligators would continue to habitat the river and floodplain, densities would decrease.

Under partial retention some flooded swamp forest would be drained and restored into seasonally flooded forest. Some floodplain swamp would be created. Floodplain swamp species such as buckthorn would benefit. Some springs that exist between Eureka and Rodman dams may be restored. Suitable bear and indigo snake habitat would increase. Suitable habitat for southern tessellated darters, bluenose shiners, and spotted turtles may increase ,but the presence of the reservoir would prevent flowing streams from being reconnected with the river. The amount of shallow water habitat would increase favoring marsh development, and may benefit round tailed muskrats and bird species including Herons, Egrets, and Ibis. Alligators may decline, but the conversion of deeper water to shallow water may benefit them.

Under full retention, the level of the reservoir would remain at 18 ft. NGVD. Marsh and aquatic habitats will continue to exist for many years, providing habitat for round-tailed muskrats, alligators and various birds that are listed as threatened or species of special concern. Southern tessellated darters should continue to exist within Orange Creek. Changes will occur under this alternative, as some trees in permanently flooded forests eventually die without replacement. Some of these areas are heavily used by Limpkins, which may decline in the distant future.

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VOLUME 19:

BIRDS OF RODMAN RESERVOIR AND THE LOWER OCKLAWAHA.

Results of the relative abundance and species richness calculations show that the greatest biological diversity occurs within habitat that contains both marsh and forest. These habitat types include edges of the reservoir, the river channel within the reservoir and those containing trees with aquatic vegetation underneath.

Under full and partial restoration the reservoir would be drained. The topography and the floodplain function would eventually return to pre-construction conditions. Aquatic habitats would be replaced by shrub communities and by floodplain swamp. This alternative would result in declines in the populations of open water and marsh dwelling species including herons, egrets, ospreys, ducks, rails, and limpkin. Increases would occur in the populations of forest birds such as warblers, viros, wrens, cardinals, and owls. (Comment - With the Ocala National Forest abutting Rodman, there is no shortage of nesting sites for forest dwelling birds, but Florida is loosing its wetlands at an alarming rate.) No threatened species is likely to be favorably affected by this alternative, but several Species of Special Concern, including three species of herons and limpkin, would be negatively impacted

Under partial retention, part of the reservoir would be retained. If the reservoir is maintained at 14 ft., areas that are currently continuously flooded would become only seasonally flooded and would succeed to floodplain swamp. Some areas that are currently marsh would become forested, and some areas of open water would become marsh. With a partially retained reservoir at 14 ft., a net increase in marsh is expected. This will enhance populations of the marsh-dwelling species listed under Full retention.

Under full retention, the level of the reservoir and the degree of flooding of the floodplain swamp downstream from Eureka would remain the same as it is now. All stressed trees would eventually disappear, resulting in fewer nesting areas for Ospreys, Cormorants, Great Blue Herons, and perhaps Limpkins. No species are expected to increase in population over current levels. (COMMENT: There are always the trees around the edges to nest in. The numbers may not be expected to go up, but they are not expected to go down either as they are in the restoration alternatives.)

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VOLUME 20:

HABITATS IN RODMAN RESERVOIR AND THE LOWER OCKLAWAHA

Data indicates the areas currently inundated by the reservoir was primarily hardwood swamp within the old river floodplain and is referred to here as floodplain swamp. Prior to the creation of the reservoir, several springs existed between Eureka and Rodman Dams. A paper dated 1971, describes 20 springs that existed before the reservoir was created. Some or all of these springs may be restored under partial river restoration.

Two types of forested communities occurred within the natural river floodplain: floodplain swamp and hydric hammock. The reservoir can be divided into three main parts: (1) pool, (2) swamp, and (3) river channel. The pool section is characterized by large areas of submerged and emergent (rooted in the bottom but grows to the surface) aquatic vegetation, standing dead trees and submerged logs and trees. The river channel resembles the natural river floodplain. However, up to a point approximately 1.2 miles downstream of Eureka Dam, the forests are permanently flooded as a result of Rodman Dam. The habitat types within the reservoir include; shallow marsh, mixed marsh, open water, floating marsh, berms, reservoir edges, shrub swamp, stressed cypress swamp, and floodplain swamp.

(Comment: It is easy to see that Rodman provides a more diversified selection of available habitats then a restored river thus accommodating a greater number of wildlife species.)

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