Citation
Post-Restoration Analysis of the Planform and Bed Morphology of the Lower Kissimmee River, Florida

Material Information

Title:
Post-Restoration Analysis of the Planform and Bed Morphology of the Lower Kissimmee River, Florida
Creator:
Black, Megan Mary
Place of Publication:
[Gainesville, Fla.]
Florida
Publisher:
University of Florida
Publication Date:
Language:
english
Physical Description:
1 online resource (62 p.)

Thesis/Dissertation Information

Degree:
Master's ( M.S.)
Degree Grantor:
University of Florida
Degree Disciplines:
Geography
Committee Chair:
Mossa,Joann
Committee Co-Chair:
Waylen,Peter Robert
Committee Members:
Walker,Robert T
Graduation Date:
12/13/2019

Subjects

Subjects / Keywords:
channelization -- connectivity -- everglades -- floodplain -- florida -- fluvial -- geomorphology -- hydrology -- kissimmee -- morphology -- nutrients -- okeechobee -- planform -- river -- water
Geography -- Dissertations, Academic -- UF
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bibliography ( marcgt )
theses ( marcgt )
government publication (state, provincial, terriorial, dependent) ( marcgt )
born-digital ( sobekcm )
Electronic Thesis or Dissertation
Geography thesis, M.S.

Notes

Abstract:
The Lower Kissimmee River is one of the most heavily altered rivers in the world. It was first completely channelized from Lake Kissimmee to Lake Okeechobee in the 1960s, leading to a collapse of the diverse aquatic system and floodplain. One year post-channelization, a restoration project began to formulate. A middle section of river was chosen for restoration and backfilling of the canal began in 1999 with the first section being completed in 2001. The restoration of the river is slated for completion in 2020. This study examines the recovery of the riverbed morphological features post-restoration by comparing historic data derived from 1901 Army Corps of Engineers Maps with bed elevation data of the modern restored river section collected by sonar, in addition to planform changes. In most undisturbed river systems, pool-to-pool spacing is five to seven times the average width of the pool channel section, and this study aims to determine whether the historic and post-restoration data meet these conditions. River depths were collected through a sonar survey of the restored section of river and exported to ArcMap for analysis. The results of the modern river data showed positive geomorphic recovery of riffles and pools for each of the river sections that were studied. The historic data did not meet the criteria of five to seven times the average width of the channel. This is likely because the depths recorded in 1901 were not thalweg depths, but centerline depths. Anthropogenic features in the floodplain may influence the current bed morphology. By comparing the bed morphology data to historic maps, historic aerial imagery, and modern imagery and LiDAR, we discuss anthropogenic and natural planform changes pre-channelization and post-restoration and the relationship between the modern planform and bed morphology. ( en )
General Note:
In the series University of Florida Digital Collections.
General Note:
Includes vita.
Bibliography:
Includes bibliographical references.
Source of Description:
Description based on online resource; title from PDF title page.
Source of Description:
This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Thesis:
Thesis (M.S.)--University of Florida, 2019.
Local:
Adviser: Mossa,Joann.
Local:
Co-adviser: Waylen,Peter Robert.
Statement of Responsibility:
by Megan Mary Black.

Record Information

Source Institution:
UFRGP
Rights Management:
Applicable rights reserved.
Classification:
LD1780 2019 ( lcc )

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POST RESTORATION ANALYSIS OF THE PLANFORM AND BED MORPHOLOGY OF THE LOWER KISSIMMEE RIVER, FLORIDA By MARY MEGAN BLACK A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE UNIVERSITY OF FLORIDA 2019

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© 2019 Mary Megan Black

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To Dutch

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4 ACKNOWLEDGMENTS Special thanks to my ad vi sor, Dr. Joann Mossa for your continued support through the completion of this thesis and the inspiration to work on the Kissimmee River. Thank you to Dr. Peter Waylen and Dr. Robert Walker for your support as my committee members. An additional gratuito us thank you to everyone in the University of Florida Geography Department for your c ama raderie through the year s of my undergraduate and graduate studies.

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5 TABLE OF CONTENTS P age ACKNOWLEDGMENTS ................................ ................................ ................................ .. 4 LIST OF TABLES ................................ ................................ ................................ ............ 6 LIST OF FIGURES ................................ ................................ ................................ .......... 7 LIST OF ABBREVIATIONS ................................ ................................ ............................. 8 ABSTRACT ................................ ................................ ................................ ................... 10 CHAPTER 1 INTRODUCTION AND BACKGROUND ................................ ................................ . 1 2 1. 1 Introductory R emarks ................................ ................................ ........................ 1 2 1. 2 R iffle A nd P ool M orphology ................................ ................................ .............. 14 2 STUDY AREA, ENVIRONMENTAL ISSUES, AND METHODS .............................. 1 7 2. 1 Study O bjectives ................................ ................................ ............................... 1 7 2. 2 Pre R estoration G eomorphology ................................ ................................ ...... 2 2 2.3 O bjectives ................................ ................................ ................................ ......... 25 2.4 Study A rea ................................ ................................ ................................ ........ 25 2.5 Geospatial A nd F ield D ata C ollection ................................ ............................... 2 5 3 RESULTS AND DISCUSSION ................................ ................................ ............... 33 3. 1 Immediate F indings ................................ ................................ ........................... 33 3.2 Anthropogenic F eatures ................................ ................................ .................... 34 3.3 Planform C hanges ................................ ................................ ............................ 35 3.4 Conclusion ................................ ................................ ................................ ........ 37 REFERENCES ................................ ................................ ................................ .............. 5 7 BIOGRAPHICAL SKETCH ................................ ................................ ............................ 6 2

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6 LIST OF TABLES Table P age 2 1 Data table. ................................ ................................ ................................ .......... 29 3 1 Bedform result table. ................................ ................................ .......................... 3 9

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7 LIST OF FIGURES Figure P age 1 1 Riffle and pool sequencing . ................................ ................................ ................ 16 2 1 Kissimmee River basin flow direction . ................................ ................................ 28 2 2 Dimensionless flow curve . ................................ ................................ .................. 2 9 2 3 Pre and post channelization flood events . ................................ .......................... 30 2 4 Study area . ................................ ................................ ................................ ......... 31 2 5 Bed differencing technique . ................................ ................................ ................ 3 2 3 1 2019 longitudinal profile . ................................ ................................ ..................... 39 3 2 2019 bedform spacing . ................................ ................................ ....................... 40 3 3 1901 longitudinal profile . ................................ ................................ ..................... 40 3 4 1901 bedform spacing. ................................ ................................ ....................... 41 3 5 Atypical pool map 1. ................................ ................................ ........................... 42 3 6 Atypical pool map 2 . ................................ ................................ ........................... 43 3 7 Atypical pool map 3 . ................................ ................................ ........................... 44 3 8 Atypical pool map 4 . ................................ ................................ ........................... 45 3 9 Atypical pool map 5 . ................................ ................................ ........................... 4 6 3 10 Atypical pool map 6 . ................................ ................................ ........................... 4 7 3 11 Atypical pool map 7. ................................ ................................ ........................... 4 8 3 12 Map of meander scars. ................................ ................................ ....................... 4 9 3 13 Map of Disston cutoffs. ................................ ................................ ....................... 50 3 14 Map of planform changes 1. ................................ ................................ ............... 51 3 15 Map of planform changes 2. ................................ ................................ ............... 52 3 16 Map of planform changes 3. ................................ ................................ ............... 5 3 3 17 Map of early cutoffs 1. ................................ ................................ ........................ 5 4

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8 3 18 Map of early cutoffs 2. ................................ ................................ ........................ 5 5 3 19 Map of early cutoffs 3. ................................ ................................ ........................ 5 6

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9 LIST OF ABBREVIATIONS DO Dissolved oxygen: Amount of oxygen dissolved (and hence available to sustain marine life) in a body of water such as a lake, river, or stream. DO is the most important indicator of the health of a water body and its capacity to support a balanced aquatic ecosystem of plants and anima ls. Wastewater containing organic (oxygen consuming) pollutants depletes the dissolved oxygen and may lead to the death of marine organisms. ha Hectares km KOE KRRP m Kilometers Kissimmee Okeechobee Everglades system Kissimmee River Restoration Project Meters

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10 Abstract of Thesis Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Science POST RESTORATION ANALYSIS OF THE PLANFORM AND BED MORPHOLOGY OF THE LOWER KISSIMMEE RIVER, FLORIDA By Mary Megan Black December 2019 Chair: Joann Mosaa Major: Geography The Lower Kissimmee River is one of the most heavily altered rivers in th e world. It was first completely channelized from Lake Kissimmee to Lake Okeechobee in the 1960s, leading to a collapse of the diverse aquatic system and floodplain. One year post channelization, a restoration project began to formulate. A middle sec tion of river was chosen for restoration and backfilling of the canal began in 1999 with the first section being completed in 2001. The restoration of the river is slated for completion in 2020. This study examines the recovery of the riverbed morphological features post R estoration by comparing historic data derived from 1901 Army Corps of Engineer s Maps with bed elevation data of the modern restored river section collected by sonar , in addition to planform changes . In most undisturbed river systems, pool to pool spacing is five to seven times the average width of the pool channel section, and this study aims to determine whether the historic and post restoration data meet these conditions . River depths were collected through a sonar survey of the restored section of rive r and exported to ArcMap for analysis. The results of the modern river data showed positive geomorphic recovery of riffles and pools for each of the river sections that were studied. The historic data did not meet the criteria of five to seven times the average width of the

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11 channel. This is likely because the depths recorded in 1901 were not thalweg depths, but centerline depths. Anthropogenic features in the floodplain may influence the current bed morphology. By comparing the bed morphology da ta to historic maps, historic aerial imagery, and modern imagery and LiDAR, we discuss anthropogenic and natural planform changes pre channelization and post restoration and the relationship between the modern planform and bed morphology.

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12 CHAPTER 1 INTRODUCTION AND BACKGROUND 1.1 Introductory R emarks Natural river systems are described as interconnected dynamic ecosystems that support an interdependence of biological and physical processes (Weins, 2002). Long term disturbances in river systems can lead to permanent alterations to critical morphological and ecologica l elements. Many of th e undergone channelization or damming in an effort to control the flow of water for flood control, for navigational purposes, water supply, and other uses (Mossa, 2015 ; Nilsson, 2005 ). These disturbances can lead to ecosystem collapse and loss of ecological integrit y by altering the longitudinal connectivity with the accompanying floodplain, as well as changing the frequency, duration, timing, and magnitude of flow (Karr & Chu, 1999 ; Poff et al., 2007 ) . Floodp lains play an important role in river health; th e se area s provide flood water storage that can help to reduce velocity during flood events (Leopold, 2017) . Additionally, they are important for sequestering carbon and for storing sediments and nutrients (Mo ssa, 2015 ; Zehetner et al. , 2009 ). R iverine ecosystems share a close relationship with other systems, such as biological (flora and fauna), chemical (water quality), and physical (geomorphic) processes (Gore & Douglas, 1995). Despite rivers being an import ant source of water, food, and recreational activities, rivers continue to be degraded by human impacts; river degradation is at an all time high (Bernhardt et al., 2005). An increase in understanding the negative impacts and degradation of alterations to rivers has led to significant funding to be spent on restoring river systems (Bernhardt et al . , 2005).

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13 Many river restoration studies focus on the rehabilitation of specific sections of the altered rivers , rather than the complete river. There are considerable studies on the restoration of small scale rivers, but fewer comprehensive studies on the impact of restoration on large r rivers (Regier et al., 1989). However, because of human growth and proxim ity of development to rivers, nearly all large sc ale rivers have been impacted or altered in some way by humans (Giller, 2005). Thus, it is vital to understand the influence of river restoration on mid sized and larger rivers. River restoration aims to resolve the loss of functions along rivers. This in cludes ecosystem goods and services, as well as restoring the damaged system to a healthier one in addition to protecting downstream and coastal ecosystems as well (Palmer et al., 2005). While river restoration is generally seen as a positive function, lit tle is known how rivers respond to restoration long term, and ecological impacts outside of the main project area must be considered (Sear et al., 2009). Sear (1996) argued that entities overseeing river restoration projects must consider the interdependen cy of fluvial processes and riverine habitats in order to achieve the desired results. Although river restoration projects are often completed using advanced engineering techniques, river managers are focusing more on ecologically based restoration to achi eve the result of improved waterways (Palmer et al., 2005). Restoration of rivers should aim to reduce the impact on the existing ecosystem (Leopold, 1948). This includes avoiding restoration during fish spawning seasons and minimizing the damage to existi ng native aquatic and terrestrial vegetation to minimize harmful impacts. Ideally, restoration efforts will be careful to avoid increasing turbidity by

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14 sending fine sediments downstream and potentially causing further harm to the aquatic ecosystem (Palmer et al., 2005). In terms of ecosystem response, there are a variety of factors that are examined during river restoration. River morphology can impact the entire riverine ecosystem and surrounding floodplain . In previous studies , species richness is found to be more substantial in restored sections of river with more morphological variability ( Schirmer et al., 2014 ). Understanding morphological recovery of restored river systems can provide important insight to how these diverse and complex systems respond to restoration. This study will focus on morphological recovery of a mid sized river in Florida by determining the riffle and pool sequencing of the modern restored river channel. 1.2 Riffle A nd P ool M orphology Riffle and pool sequences are shallow and deep be d forms commonly found in gravel , sand, and mixed bed fluvial systems that are formed by the interaction of flow and sediment transport (Figure 1 1 ). They are not necessarily identified by differences in depth, but instead by differences in energy gradient. Riffles are the shallower formations, and river channel width along these sections tends to be wider than pools at all stages of flow (Richards, 1976). Pools form as a result of scouring that lead s to alternating depressions in the riverbed and separated by riffles, which are composed of larger, co arser sediments than pools (Clifford and Richards, 1992). These riffle formations have an energy gradient that is steeper than the average energy g radient of the entire river system . Pools are deeper formations with lower velocity, or an area of the river where the energy gradient is lower than the average

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15 energy gradient of the entire river cycle (Yang, 1971). The combination of dispersion and so rting of sediments in the water column is the primary cause for the development of riffles and pools. These features can be formed or influenced by other features in the river channel, such as large woody debris, bank projections, boulders, and bedrock (Mo ntgomery et al., 1995). Sediment transport in these riffle and pool sequences can be described as finer grained sediments moving from riffles to pools at low flows, due to shear stress or velo c ity being at a maximum over riffles (Sear, 1996). The development of these bedforms are influenced by a variety of factors. A study by Wohl et al. (1992) suggests that channel gradient , discharge, and erosional resistance of channel boundaries are all partially responsible for the even formation of riffles an d pools. The size and spacing of bedforms is often considered to be related to flow conditions and sediment size (Lisle, 1982). However, it is generally widely accepted that channel width influences the spacing between riffles and pools, suggesting that ch annel width plays an important role in the development of these features (Langbein and Leopold, 1964) . Riffles and pools create important habitat for a large variety of aquatic biota . Specifically, these features are a macrohabitat or mesohabitat that cre ate a full set of conditions necessary for the complete life cycle for many species of fish (Maddock, 1999). Riffle habitats support a variety of benthic species, especially in riverine systems that experience seasonal fluctuations in flow. These benthic o rganisms require flow to provide oxygen, food, and low silt subtrate, making riffle habitats a n attractive habitat for certain species of these organisms (Brown & Brussock, 1991). Some species of fish and mussels prefer the lower velocity pools to riffl es (Graf, 1997).

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16 There are few studies regarding the response of large scale rivers to restoration from the standpoint of riffle and pool recovery. A study by Gregory et al. (1994) indicates that low order streams experience recove ry of riffle and pool mor phology within 16 years of major channelization. This study will focus on riffle and pool morphological recovery in the Kissimmee River, a mid sized river with a basin of 7800 km 2 in south central Florida that was channelized between 1962 and 1971 and was more recently restored starting in 2000 (Nico, 2005) . Additionally, channel cutoffs made prior to 1901 and between 1901 and 1950 are documented with historical analysis. Figure 1 1. Longitudinal profile and planform view of riffle and pool sequencing (Jennings and Harman, n.d.).

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17 CHAPTER 2 STUDY AREA, ENVIRONMENTAL ISSUES, AND METHODS 2.1 Study O bjectives The Lower Kissimmee River was historically filtering water th roug h extensive floodplain before entering the Everglades wetland system south of Lake Okeechobee (Figure 2 1) . This system currently provides drinking water for over 6 million people in south Florida. The Kissimmee watershed covers approximately 7800 km 2 and forms the headwaters of the Kissimmee River Lake Okeechobee Everglades system (KOE) . The elevation of the headwater s near Orl ando, Florida are approximately 100 m in elevation. This area is known as the Chain of Lakes, comprised of a variety of lakes and sinkholes (Kindinger et al., 1999). The Lower Kissimmee River historically meandered 166 kilometers from Lake Kissimmee to Lak e Okeechobee in a low gradient trough (0.07 m/km) formed during the late Tertiary (Jordan & Arrington, 2014 ; White, 1970 ). The pre channelized river was sinuous ( 1.67 to 2.1) with a bankfull width between 15 and 35 m, and depths between 1 to 3.5 m (Koebel, 1995). Historic lake water levels were variable, fluctuating between 14 m and 17 m in Lake Kissimmee and 3 to 7 m at Lake Okeechobee (Anderson and Chamberlain, 2005). The pre channelized river had an average width of between 15 to 36 m and an average depth of between 1 and 3.5 m. The original channel had natural levees that varied in size along the river, sometimes along both sides, or only one side or neither side, with flat flood plain instead. Historic imagery indicates that some sections of the natural Kissimmee River resembled an anastomosing channel, rather than a meandering channel (Warne et al., 2000).

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18 The floodplain of the historic Lower Kissimmee River was unique among other North American rivers. Originally 18,000 ha, the floodplain contained at least seven different plant community types and existed as wintering habitat for 19 migratory waterfowl species and 21 species of wading birds year round. The prolonged inundation of the floodplain allowed for prolific biological, chemical, an d physical interactions between river and floodplain . Vegetation on the floodplain acted as a filtration system, removing excess nutrients and f i ltering sediments. During periods of inundation, fish were able to move between the floodplain and river to breed and spawn. Energy inputs from the floodplain as flood levels receded helped to provide a supportive food base for larger species of fish, such as the largemouth bass and 38 other fish species (Toth, 1995) The flood pulse was largely driven by thick vegetation in the floodplain, extensive wet season precipitation, and several hydrogeomorphic factors. These factors include limited capacity for ouflow of the upper basin, underdevelop ed drainage in surrounding watersheds, low slope of the river valley, floodplain constrictions, and a bottleneck effect where the river flows into Lake Okeechobee (Toth et al., 2002). Prior to channelization, the area was of great ecological importance an d was home to a large variety of native flora and fauna. The prolific 18,000 ha floodplain was 95% inundated with water for up to six months out of the year. The unaltered rier had low, natural levees covered by willows and wetland shrubs, with the floodpl ain consisting of broadleaf marsh, wet prairies, and live oak hummocks ( Toth et al., 1995 , Mossa, 2015). It is estimated that 48 species of fish, 26 species of waterfowl, 17 species of wading birds, and several hundred species of other aquatic plants and

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19 i nvertebrates were found within the historic Kissimmee River and its floodplain (Dahm et al., 1995). The frequently indundated floodplain allowed for copious spawning habitat for many of these fish and benthic invertebrate species . Although ecologically val uable, this region were often targeted for development. The vast, open land was thought to be ideal for agricultural uses and for the expanding population of Florida in the 1800s and beyond. Discussion of channelization was frequent, beginning with entrepenuer Hamilton Disston in February 1881 . Disston contracted with the State of Florida to drain the land surrounding the Kissimmee River in exchange for ownership of 50% of the reclaimed land (SFWMD, 2005). Prior reports s uggest that Disston made some artificial cutoffs with a dredge , but the se locations have not been documented. was to drain the upper Kissimmee valley, and reportedly sent one dredge south to Lake Okeechobee. This dredge created cuto ffs of several meander bends in the river ; (Grunwald, 2006). A survey of the river from Lake Kissimmee to Lake Okeechobee was constructed in 1901 by the Army Corps of Engineers (led by Captain T. H. Rees) provides some early information to assess potential cutoff sites, as well as the bed morphology prior to considerable disturbance . . After a major hurricane and other climatic events caused widespread flooding in the 1940s, the state of Florida began planning the complete channelization of the river and subsequent draining of the Lower Kissimmee floodplain. Channelization of the L ower Kissimmee R iver began in 19 6 2 by the Army Corps of Engineers and was completed in 197 1 . The channelization of the river was part of the Central and Southern

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20 Florida Flood Control Project , developed in 1948 to regulate water levels and manage water in South Florida . The meandering riv er and floodplain ecosystem was converted into a 90 km long, 100 m wide, and 9 m deep canal. The canal was separated by five pools with lock structures to control the water levels in the canal . This project aimed to lower peak and average flood stages and eliminate water level fluctuations ( Toth et al., 1998 ). The resulting canal allowed for large amounts of stormwater (110 m 3 /s ) to be moved at low velo c ities (less than 0.3 meters per second) ( W ha len et al, 2002 ). Where historic flows were continuous from the headwater lakes and experienced seasonal variability, the canal discharges were irregular, and the canal regularly had no flow at all for several months. The sinous historic channel was left intact, with the e xclusion of where the canal crossed the channel, but the remnant channel was nearly stagnant . After the completion of the channelization project , it became evident that there were drastic negative impacts to the ecosystem. Dissol v ed oxygen (DO) levels in the canal were below 2 mg/L in the summer and fall months. This can be attributed to high nutrient levels in the water column. These levels are lethal to most fish and aquatic invertebrates ( Toth, 1993 ). While DO levels were greater during certain periods, the long term low levels of DO led to long term degradation in the channel. It is estimated that over five billion small freshwater fish and six billion freshwater shrimp lived in the 14,164 ha of floodplain drained due to channelization (Toth, 1990) . The loss of these aquatic biota created a negative impact on the food chain. These fish and invertebrates were important food sources, supporting the rest of the food web. Subsequently, larger fish species and other aquatic fauna populations experie nced population loss (Miller, 1990). Only low oxygen species of fish were able to remain in the canal . Because of

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21 the loss of fish and invertebrates in the water column, w intering waterfowl populations declined by 92% . Bald eagle annual active terriroties were observed to have declined by 7 4 % in the floodplain ( Shapiro et al., 1982 ) . B i odiversity was greatly diminished and population density of the fauna that remained was very low. Nearly 44% of fo r mer riparian wetland was converted to pastureland (Milleso n et al., 1980) . Downstream nutrient loading increased by 22% after channelization . The historic floodplain had significant nutrient removing capabilities and acted as a filter to remove excess nutrients. Without this filter, excess nutrients from agricult ure in the region were filtered directly downstream and into Lake Okeechobee (Toth, 1995). Public outcry regarding the channelization of the Kissimmee River began before the c h annelization project was complete. Restoration was set into motion by the U.S. Geologica a S urvey after data were collected from Lake Okeechobee, indicating that the lake was undergoing accel erated rates of eutrophication from high nutrient levels in response to the channelization of the Kissimmee Rive r (Toth, 1995). In 1976, only five years after channelization, Florida legislature passed the Kissimmee Restoration Act. This act aimed to develop measures to restore the Kissimmee River ecosystem and alleviate issues caused by channelization of the river (Toth, 1990) . In 1983, a parti al backfill plan was developed to restore a section of the Kissimmee River in an effort to improve water quality and biodiversity. Flow was to be diverted from the canal to remnant river channels, and the existing spoil was to be deposited back into the ca nal (Toth, 1995). Restoration of a section of river was authorized with the Water Resources Development Act of 1992 through the U.S. Congress. A 300 m section of river was

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22 chosen for a pilot dechannelization project that was completed in 1994 to understa nd how the floodplain and river would recover on a small scale. I n addition to this section of river being dechannelized, spoil mounds were removed from roughly 5 ha of adjacent floodplain (Toth, 1996). It was determined that the restoration project could be accomplished without major impacts to downstream water quality (Colangelo & Jones, 2004). Although this project was too small to truly understand the impacts of restoration or restore a major section of river and floo d plain , the return of fish and bird populations to this pilot restoration section provided positive supporting evidence to support further restoration (Toth et al., 1998). 2.2 Pre R estoration G eomorphology The remnant river channels of the Kissimmee River lacked flow during the period of channelization. Core samples showed that o rganic material deposits ranging in thickness from 1 to 98 cm (with an average of 14 cm in the section to be restored) accumulated over the natural bed substrate in these remnant sections (Bousquin et al., 2005) . Cross sections of these sections indicated that despite the organic material, the channeliation morphology. Organic deposits reduced t he average depth of the channel by 8% and reduced the cross sectional area of the channel by 8%. The width to depth ratio of remnants channels was increased by 13%. Additionally, none of the 82 meander bends on the remnant channels showed signs of active p oint bar formation (Bousquin et al., 2005) . This strongly indicates that channelization prevented sand transport and deposition. Lack of flow in the channel and stabilized water levels allowed for terrestrial plants to become established along the point ba rs that were established prior to channelization (Bousquin et al., 2005) .

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23 The main restoration project began in 1999 and involved removing two water control structures (S65B and S65C ) and backfilling a portion of the canal to restore flow to the natura l river. The construction area was separated into four phases . Phase 1 was the first section to be completed in 2001. Phase V1A was completed in 2007, and Phase V1B was completed in 2010 (Figure 2 4 ). A final section is currently under construction. To dat e, 43 km of natur a l iz ed ri v er channel have been restored, with the complete length of restoration being 70 km. This project is slated for completion in 2020 . The restoration has allowed for several thousand hectares of floodplain to experience intermittent inundation . Inputs of fluvial sediments from floodplain indundation are key to the health of the floodplain (Toth et al., 1995). The physical and biological response to the res t oration of the Kissimmee River to date has been positive. Soon after flow was restored to Phase 1, the river showed metabolism parameters similar to that of other blackwater rivers in the southeastern United States (Colangelo, 2007). Sediment studies indicate restored connectivity betw een the extensive floodplain system and the streamflow in the naturalized river channel. Sediment transport and sediment yields in the river are comparatively similar to that of other low gradient streams in the region (Schenk et al., 2012). Studies on wad ing birds and waterfowl suggest that populations have risen greatly in the construction phases that have been completed. The return of the flood pulse cycle has greatly improved wetland vegetation, hydrology, and fish and invertebrate communities. The posi tive impact of river restoration has enabled wading birds and waterfowl to reestablish populations in the Kissimmee River Floodplain. Bird populations that are dependent on annual vegetation have recovered more quickly than those that are reliant

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24 on fishes and invertebrates because it takes these aquatic biota longer to recover than plants. In a 2014 study, over 95% of observed waterfowl species were the blue winged teal and mottled ducks that eat both invertebrates and seeds (Cheek et al., 2014). Post res toration studies on the sediment transport of the river show that suspended sediments in the water column range from 2% sand at low flows, and up to 78% sand at higher flows (Mossa et al., 2009). No previous data exist on sediment transport in the Lower Ki ssimmee River prior to channelization or restoration. It is thought that the suspended sand may be derived from bank erosion, or potentially from the construction of the restoration project. In terms of cost of the project, extent, and ecological manipulat ions, the Kissimmee River Restoration Project (KRRP) is one of the largest and most extensive river restoration projects ever to take place (Koebel & Bousquin, 2014). The cost to date is close to $980 million and could continue to rise before it is complet ed ( Castillo et al. , 201 6 ). 2.3 Objectives This study seeks to unders t and the recovery of the river bed morphological features post restoration by comparing historic data derived from 1901 Army Corps of Engineers Maps with bed elevation data of the moder n restored river section collected by sonar imagery. In most undisturbed river s systems, pool to pool spacing is five to seven times the average width of the pool channel section ( Leopold et al., 1964, Richards, 1976 ) , and this study aims to determine whet her the historic and post restoration data meet these conditions. This study will also explore lasting affects of anthropogenic features (specify, this comes out of thin air) on the floodplain to the

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25 modern river channel and bedforms. Additionally, changes in the planform will be examined by comparing the 1901 Army Corps of Engineers Maps, the 1950s aerial imagery, and 2015 aerial imagery. 2. 4 Study A rea The study area encompasses a 43 km stretch of the Lower Kissimmee River that has been restored to its pre channelization planform. The study area is separated into the three sect ions of completed restoration (Figure 2 4 ). Phase 1 was completed in 2001, Pha se 1VA was completed in 2007, and Phase 1V was completed in 2010 . 2. 5 Geospatial A nd F ield D ata C ollection The 1901 Army Corps of Engineers maps were collected and analyzed and the earliest available aerial imagery from the 1950s were used for georeferencing (Figure 3 1) from a prior project (Mossa et al, 2009) . The 1901 maps contained over 5,000 depth points t hat were each individually digitized in ArcMap. These points were approximately spaced 30 m apart. Water surface elevations were recorded on these historic maps and used to calculate bed elevations. A river centerline was created using these points. Additi onally, a longitudinal profile of the historic river was developed using these points (Figure 3 2) . The bed differencing technique was also used on these data in an effort to identify riffles and pools to use the historic data as a baseline, and to determi ne whether the historic data would meet the standard five to seven channel width spacing. Field work was conducted in January 2019 using a four meter Gheenoe launched from the Istokpoga boat ramp along the Istokpoga canal, southwest from the study area. The Istokpoga canal connects to the right bank of the Kissimmee River channel, at the very southern end of the KRRP. River depths were recorded by using a

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26 Humminbird Helix 5 G2 CHIRP GPS Sonar and transducer mounted to the bottom starboard side of the tra nsom to reduce noise interference from the propeller . The 4 3 kilometers of the river were traversed twice (upstream and downstream) using the single beam sonar in a zigzag swath across the river channel to collect depths. Obstacles in the channel preven ted a complete swath of the entire river at some points, preventing complete coverage of the river channel. Twelve m anual depths were also recorded as waypoints on the sonar control head to ensure the accuracy of the sonar data. Following the collection o f these data, the depth points were uploaded from the sonar control head micro SD card to Humminbird PC. This software allows for the waypoints and tracks saved to be exported and used for analysis in ArcGIS. These data were exported to Excel. The deeper o f both measurements was chosen to create a thalweg of the riverbed profile. A complete longitudinal profile was developed of the thalweg using a spacing of 10 m (Figure 3 1) . The bed form differencing technique was used on the 10 m thalweg data for the purpose of identifying riffles and pools of the bed profile. This technique involves differencing the values from upriver to downriver , focusing on the cumulative elevation change ( E i ) sinc e the last bedform, rather than on amplitude or elevation change. Bedforms are identified by series; one series is an uninterrupted sequence of these differenced values of the same sign (+ or ). A tolerance value (T) is developed using the standard deviat ion of the differenced successive thalweg bedform values (where the bed elevations are B 1 , B 2 , B 3 , B 4 , differencing the values is B 1 B 2 , B 2 B 3 , B 3 B 4 This tolerance value is used to differentiate riffles from pools and is the minimum

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27 absolute value of E i used to identify a feature as a riffle or pool. The end point of a series is the absolute minimum or absolute maximum, where |E i | . This end point identifies the bedform feature as a riffle or pool, and resets to zero once a bedform is identified (meaning the next bedform will be identified based on the latest bedform, using T). If a bedform feature is |E i | < T for a series , that bed form will be identified as a local maximum or local minimum and not regarded as a bedform. T will still be based on the former absolute maximum or absolute minimm bedform that precedes the local maximum or local minimum (Figure 2 5). For this study, the st andard deviation of the differenced values for each of the three construction areas (Phase 1, Phase 1VA, and Phase 1VB was found to be very close to 1. These numbers were rounded up or down to 1 for the purpose of differentiating the riffles from pools, th erefore, the tolerance value was equal to 1.0 m. Riffles and pools were then identified manually by evaluating each series and whether or not each bedform in a series was equal to or greater than the tolerance value of 1.0 meter.

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28 Figure 2 1. The Kissimmee River showing direction of water flow south to the Everglades.

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29 Table 2 1. Summary of data, spatiotemporal resolution, data acquisition date, and source. F igure 2 2. Dimensionless flow duration curves for the Kissimmee River, indicating the changes in water levels for two 30 year periods; pre channelization (1930 1959) and post channelization (1970 1999) (Mossa, 2015).

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30 Figure 2 3. Flooding events with similar discharge levels on the Kissimmee River pre and post channelization. The lef t figure illustrates a flood event prior to channelization and shows velocities within the river channel and the surrounding flooplain. The right figure illustrates similar discharge levels in 1987. Both stage and thalweg are lower, with the flow containe d entirely to the canal (Mossa, 2015).

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31 Figure 2 4. The Lower Kissimmee River study area indicating the former C 38 canal and other anthropogenic features, such as roads, smaller canals, or locks.

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32 Figure 2 5 . A hypothetical example of a river longitudinal profile indicating the bed differencing technique and notations . A series is an uninterrupted sequence of the difference values (these values will have the same sign, + or ). The elevation change (E i ) is a sries ele vation change and is the sum of the difference values for all points within the ith series from the last identified bedform. between bedforms is reset after each bedform that exceeds the tolerance value (T). If |E i | for a series, then the end point of that series is either an absolute minimum or absolute maximum to form a riffle or pool. I n this diagram, E 1 of the first series (riffle sequence ) denotes features that do not meet T. The second elevation change, or E 2 , also does not meet the tolerance value. E 3 does meet the tolerance value; here, E i is equal to the sum of the E i from the last identi f ied bedform and this bedform will be identified as a pool. Since the Ei between bedforms is now reset, the next bedform to change sequence in th e new series must again be |E i | . In this hypothetical example, the first bedform is |E i | , meeting the absolute maximum to be identified as a riffle.

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33 CHAPTER 3 RESULTS AND DISCUSSION 3.1 Immediate F indings Th ree construction phases of the Kissimmee River were analyzed separately . Phase 1, the first restored section completed in 2001, has 91 bedforms and a mean width of 36 m. The mean wavelength of this section was 246 m, with pool spacing of seven times the width of the channel. Phase 1VA, completed in 2007, has a total of 1 8 bedforms and a mean width of 36 m. The mean wavelength of this section is 181 m, and the spacing between pools was found to be 5 times the widt h of this channel section. The final section, Phase 1VB, was completed in 2010 and has a total of 42 bedforms with an average width of 36 m. The average wavelength of this section was found to be 267 m, with an average pool spacing of 7.5 times the width of the channel (Table 3 1 and F igure 3 2 ) . All three of the tested sections display an average with between or near five to seven times the average width of the channel of the construction sections. Th ese results indicate positive geomorphic recovery of the channel and riverbed post restoration. The historic data were more erratic than would be expected . Pool spacing rang ed between 9 to 14 times the average width of the channel (Table 3 1 and F igure 3 4 ) . This is likely caused by inaccurate data collection . Considering these depths were collected in 1901, it is difficult t o know whether or not the Army Corps of Engineers were following the thalweg of the Kissimmee River. Based on the larger than expected spacing between pools, we can assume that the Army Corps of Engineers were following the river centerline, rather than the thalweg. Therefore, these historica l data can not be use d to identify the bed morhpology of the 1901 Kissimmee River. However, these data

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34 and more modern aerial imagery from the 1950s can provide us with further insights to how the planform of the river changed over time. We are able to identify early human made cutoffs, such as those created by Hamilton Disston in the late 1800s. 3.2 Anthropogenic F eatures Despite the positive recovery of riffles in pools, the modern restored section of river is still greatly characterized by anthropogenic features. Sections where roads, canal locks, or canals crossed the modern restored channel display more atypical bedform s than the undisturbed reaches of river channel. Of the 15 1 pool bedforms along the restored channel, 3 0 display lengths that are considered to be longer than expected . In this study, we classify bedforms that are longer than 300 m as atypical lengths. Of these features, 15 either cross or are immediately upstream or downstream of an anthropogenic feature. The modern river channel crosses the former C 38 canal seven times, with seven of these crossing displaying atypical pool lengths (Figures 3 5 3 11 ) . T his indicates the potential negative impact of anthropogenic features on the restored river channel bed morphology . It is likely that these sections will recover morphologically in the future, but studies indicate that bed morphology may not recover for up to 16 years ( Gregory et al., 1994 ). Another pool that is greater than 300 m in length crossed one of two man made cutoff s in the study area . This cutoff was created sometime between 1901 and the 1950s. The meander that was cutoff at this section still contained water through the 1950s but became an oxbow lake after the cutoff was made and eventually filled in with sediments during channelization and post restoration ( Figure 3 17 ) . Two additional cutoff s w ere created during the same time period, but the bed morphology of th ese

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35 f eature s are not atypical ( Figure s 3 18 and 3 19 ). Because of a lack of more artificial cutoffs in the study area, it is difficult to fully understand the impacts and implications that s uch alterations may have on bed morphology. 3.3 Planform C hanges The 1901 Army Corps of Engineers planform maps provide insight to the natural formation of the river channel with the earliest historic data that is available. We can use these maps to identify changes in the planform and potential human alterations by comparing the maps to aerial imagery from the 1950s to understand how the river changed naturally, as well as how small scale manipulations may have altered the planform prior to major mo dification in the 1960s and 1970s. These maps also show potential locations for the early cutoffs created by Hamilton Disston in the 1880s. These locations have not been previously identified. The potential Disston cutoffs are displayed by irregular meande r cutoff features (Figure 3 13). T hree man made cutoffs that were created between 1901 and 1950 , potentially created by the Army Corps of Engineers via the Federal Navigation Project of 1902, are identified by comparing our two historic datasets (Army Cor ps of Engineers, 1996). These cutoffs do not display natural formations or characteristics of natural meander cutoffs. The base of the meander bend is very wide (Figure 3 17 ). Meander bend cutoffs often naturally occur when the progressive migration of a meander bend eventually migrates into itself (Zinger et al., 2011). This type of cutoff is known as a neck cutoff. Human manipulation at these cutoffs is often apparent becau se the river channel would not have been forced through this feature without some type of outside alteration. The progressive narrowing of the limbs of the river around the meander eventually break

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36 through the meander neck. It is possible for headward eros ion to create a chute cutoff that would develop along a wider meander neck (Gay et al., 1998). However, in the 1950s aerial imagery, we can observe some evidence of human alterations in the form of levees or spoil that was removed from the channel to creat e the cutoff (Figure s 3 14 3 16 ). The migration of the channel would likely have eventually caused a natural cutoff here as the base of the meander bend narrowed, which would allow for a flood or lateral migration to break th e neck and leav e behind an oxbow lake. Oxbow lakes in the Kissimmee River floodplain support a broad variety of aquatic flora and fauna and are primarily dominated by broadleaf marsh (Shen et al., 1994, Merritt et al . , 1996). Connectivity of the river channel and oxbow lakes during flood events can help to aid this critical habitat. These lakes collect a significant amount of organic sediments and eventually fill in over long periods of time. The 2019 planform is very similar to that of the 1901 planform, excluding a few areas with local avulsions, lateral channel migration, artificial and natural cutoffs, and other anthropogenic activites ( Figure 3 14 3 16). The floodplain of the Kissimmee River has migrated historically and has many meander scars can be seen in aerial imagery fro m the 1950s ( Figure 3 13). This indicates that the river likely changed course many times throughout its history. When comparing the data from the 1901 Army Corps of Engineers maps to the aerial imagery from the 1950s, it is evident that not many changes o ccurred over these five decades. Changes between the 1950s and channelization in the 1960s were slight ( Figure s 3 14 3 16). It can be assumed that without human modification at all that the planform of the river might be completely different than it is t oday. The channel planform was hindered without the natural

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37 flooding processes between the river and floodplain for the three decades that the river was channelized. Additionally, the restored reach of river can not entirely be described as natural given t hat the upper and lower reaches are still channelized with no plans of restoration. 3.4 Conclusion The geomorphology of the restored section of the Lower Kissimmee River displays bed form morphology typical to that of a natural meandering alluvial river. Bed forms were found to be spaced within the standard expected distance of five to seven times the average width of the river channel for each section. Following restoration efforts, it is possible that the organic sediment deposits that collected within t he remnant river channel sections were flushed downstream once flow was restored. The remnant channels were devoid of flow for several decades; however, this may not have been long enough to permanently alter the bed morphology of the natural river channel . The areas that displayed some type of anamolous bed features in the river were found to cross some type of anthropogenic feature (former road, lock, or canal). These sections may take longer to reform to the natural bed morphology. Future studies on the river will be necessary to determine how these portions of channels have reformed or changed over time. Limited historic data exist for the bed morphology of the Kissimmee River prior to channelization. The 1901 Army Corps of Engineers maps offer signific ant insight to the original, natural river planform and some insight to the bed morphology of the river. These data are not accurate enough to develop a comprehensive understanding of the river in its most natural state because it is unlikely that the Army Corps of Engineers

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38 took a trajectory that followed the thalweg of the river, but instead followed the centerline. Therefore, it is difficult to know whether the existing bed morphology is what should be expected for this river. However, the length of the pool segments of the modern restored river section and average width of each segment are what would be expected for a river of this size in alluvium. Studies of remnant channels prior to restoration indicate that the remnant channels maintained typical bed morphology, although these sections contained large amounts of organic material deposited on the bed due to lack of flow. These studies indicated typical sandy substrate below organic deposits and found that the morphology was intact beneath. Human altera tions to the planform of the historic Kissimmee River prior to channelization may have influenced the current planform and morphology of the restored river. Early cutoffs created by Hamilton Disston and possible cutoffs created by the Army Corps of Enginee rs prior to 1960 have likely driven the river to follow the course that it follows today. Aerial imagery of the study area from the 1950s indicates three artificial cutoffs since 1901, through which the modern restored river channel follows. The remnant ch annels or oxbows where the river once flowed are still apparent as meander scars but are no longer active parts of the river channel. Few sections of the restored river were very heavily altered prior to channelization. Without human influence, it can be a ssumed that the modern river would take a different course.

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39 Table 3 1. Summary of bedforms from the 2019 and 1901 data. Figure 3 1. Longitudinal profile of the Lower Kissimmee River in 2019.

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40 Figure 3 2 . Bedform spacing and relative frequency of the Lower Kissimmee River in 2019 Figure 3 3. Longitudinal profile of the Lower Kissimmee River in 1901.

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41 Figure 3 4. B edform spacing and relative frequency of the Lower Kissimmee River in 1901.

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42 Figure 3 5 . Map indicating atypical pool lengths crossing the former C 38 canal.

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43 Figure 3 6 . Map indicating atypical pool lengths crossing the former C 38 canal and former road and smaller canal within the floodplain.

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44 Figure 3 7 . Map indicating irregular pool length s near the former S65B lock . The length of the se pool s at this section is atypical for this river.

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45 F igure 3 8 . Map indicating a n artificial cutoff created sometime between 1901 and 1950s. The length of the pool at this section is atypical for this river.

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46 F igure 3 9 . Map indicating atypical pool lengths near former anthropogenic features, including the C 38 canal.

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47 Figure 3 10 . Map indicating a manmade cutoff created sometime between 1901 and 1950s. The length of the pool at this section is atypical for this river.

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48 Figure 3 11 . Map indicati ng two irregular pool lengths crossing the C 38 canal and another former smaller canal in the floodplain . The length of the se pool s at this section is atypical for this river.

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49 F igu re 3 1 2 . Map identifying potential cutoffs created in the 1880s by Hamilton Disston.

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50 F igure 3 13 . An example section of river displaying meander scars from the natural migration of the river channel prior to channelization.

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51 Figure 3 14 . Upper study area p lanform chang es between 1901, the 1950s, and 2019.

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52 Figure 3 15 . Upper study area planform changes between 1901, the 1950s, and 2019.

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53 Figure 3 16. Map depicting changes between the 1901, 1950s, and 2019 planforms.

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54 Figure 3 17 . Cutoff created between 1901 and 1950. The top image is the Army Corps of Engineers map of this section, followed by the 1950s aerial of the early cutoff, and more recent modern LiDAR imagery showing potential changes to the floodplain due to the cutoff.

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55 Figure 3 18 . Cutoff created between 1901 and 1950. The top image is the Army Corps of Engineers map of this section, followed by the 1950s aerial of the early cutoff, and more recent modern LiDAR imagery showing potential changes to the floodplain due to t he cutoff.

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56 Figure 3 19 . Cutoff created between 1901 and 1950. The top image is the Army Corps of Engineers map of this section, followed by the 1950s aerial of the early cutoff, and more recent modern LiDAR imagery showing po tential changes to the floodplain due to the cutoff. The original channel in this section was completely destroyed by the C 38 canal, leaving behind no remnants of the cutoff.

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57 REFERENCES Anderson, D. H., & Chamberlain, J. R. (2005). Impacts of channelizati on on the hydrology of the Kissimmee River, Florida. In D. H. Anderson, S. G. Bousquin, G. W. Williams, & D. J. Colangelo (Eds.), Establishing a baseline: Pre restoration studies of the channelized Kissimmee River, Technical Publication ERA #432. West Palm Beach: South Florida Water Management District. Army Corps of Engineers . (1996). Final Supplemental Environmental Impact Statement/Environmental Impact Report. Supplemental Information Report. doi:10.21236/ada436416 Bernhardt, E. S., Palmer, M. A., Allan, J. D., Alexander, G., Barnas, K., Brooks, S., ... & Galat, D. (2005). Synthesizing US river restoration efforts. Bousquin, S. G., Anderson, D. H., Williams, G. E., & Colangelo, D. J. (2005). Establishing a baseline: pre restoration studies of the channelized Kissimmee River. South Florida Water Management District, West Palm Beach, Florida, USA. Brown, A. V., & Brussock, P. P. (1991). Comparisons of benthic invertebrates between riffles and pools. Hydrobiol ogia, 220(2), 99 108. Castillo, D., Kaplan, D., & Mossa, J. (2016). A synthesis of stream restoration efforts in Florida (USA). River Research and Applications, 32(7), 1555 1565. Cheek, M. D., Williams, G. E., Bousquin, S. G., Colee, J., & Melvin, S. L. (2014). Interim response of wading birds (Pelecaniformes and Ciconiiformes) and waterfowl (Anseriformes) to the Kissimmee River restoration project, Florida, USA. Restoration ecology, 22(3), 426 434. Clifford, N. J. & Richards, K. S. (1992): The Reversal hypothesis and the maintenance of riffle pool sequences: a review and field appraisal. In: Cartling, P. A. & Petts, G. E. (eds.): Lowland floodplain rivers: geomorphological perspectives. Wiley, 44 70. Colangelo, D. J. (2007). Response of river metaboli sm to restoration of flow in the Kissimmee River, Florida, USA. Freshwater Biology, 52(3), 459 470. Colangelo, D. J., & Jones, B. L. (2005). Phase I of the Kissimmee River restoration project, Florida, USA: impacts of construction on water quality. Enviro nmental Monitoring and Assessment, 102(1 3), 139 158. Gay, G. R., Gay, H. H., Gay, W. H., Martinson, H. A., Meade, R. H., & Moody, J. A. (1998). Evolution of cutoffs across meander necks in Powder River, Montana, USA. Earth Surface Processes and Landforms : The Journal of the British Geomorphological Group, 23(7), 651 662.

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58 Graf, D. L. (1997). Sympatric speciation of freshwater mussels (Bivalvia: Unionoidea): a model. American Malacological Bulletin, 14, 35 40. Gregory, K. J., Gurnell, A. M., Hill, C. T., & Tooth, S. (1994). Stability of the pool riffle sequence in changing river channels. Regulated Rivers: Research & Management, 9(1), 35 43. Grunwald, M. (2006). The swamp: The Everglades, Florida, and the politics of paradise. Simon and Schuster. Jenning s, G., & Harman, W. (n.d.). Natural Stream Processes | NC State Extension Publications. Retrieved from https://content.ces.ncsu.edu/natural stream processes Jordan, F., & Arrington, D. A. (2014). Piscivore responses to enhancement of the channelized Kissi mmee River, Florida, USA. Restoration ecology, 22(3), 418 425. Kindinger, J. L., Davis, J. B., & Flocks, J. G. (1999). Geology and evolution of lakes in northcentral Florida. Environmental Geology, 38, 301 321. doi:10.1007/s002540050428. Langbein, W. B., & Leopold, L. B. (1964). Quasi equilibrium states in channel morphology. American Journal of Science, 262(6), 782 794. Leopold, L. B., Wolman, M. G. and Miller, J. P. (1964). Fluvial Processes in Geomorphology, San Francisco, Freeman, 522pp. Leopold, L. B. (2017). Flood hydrology and the floodplain. Journal of Contemporary Water Research and Education, 95(1), 2. Lisle, T. E. (1982). Effects of aggradation and degradation on riffle pool morphology in natural gravel channels, northwestern California. Water Resources Research , 18 (6), 1643 1651. Maddock, I. (1999). The importance of physical habitat assessment for evaluating river health. Freshwater biology, 41(2), 373 391. Merritt, R. W., Wallace, J. R ., Higgins, M. J., Alexander, M. K., Berg, M. B., Morgan, W. T., ... & Vandeneeden, B. (1996). Procedures for the functional analysis of invertebrate communities of the Kissimmee River floodplain ecosystem. Florida Scientist, 216 274. Montgomery, D. R., B uffington, J. M., Smith, R. D., Schmidt, K. M., & Pess, G. (1995). Pool spacing in forest channels. Water Resources Research, 31(4), 1097 1105. Mossa, J. (2015). Geomorphic Perspectives of Managing, Modifying, and Restoring a River with Prolonged Flooding : Kissimmee River, Florida, USA. In Geomorphic

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59 Approaches to Integrated Floodplain Management of Lowland Fluvial Systems in North America and Europe (pp. 143 169). Springer, New York, NY. Mossa, J., Gellis, A. C., Hupp, C. R., Pearman, J. L., Garfield, U. , Schenk, E. R., ... & Habermehl, P. J. (2009). Streamflow and fluvial sediment transport in Pool C, restored section of the Kissimmee River: Chapter 2. Nico, L. G. (2005). Changes in the fish fauna of the Kissimmee River Basin, peninsular Florida: nonnat ive additions. In American Fisheries Society Symposium (Vol. 2005, No. 45, pp. 523 556). Nilsson, C., Reidy, C. A., Dynesius, M., & Revenga, C. (2005). Fragmentation and flow 408. doi:10.112 6/science.1107887. O'Neill, M. P., & Abrahams, A. D. (1984). Objective identification of pools and riffles. Water resources research, 20(7), 921 926. Palmer, M. A., Bernhardt, E. S., Allan, J. D., Lake, P. S., Alexander, G., Brooks, S., ... & Galat, D. L. (2005). Standards for ecologically successful river restoration. Journal of applied ecology, 42(2), 208 217. Richards, K. S. (1976). Channel width and the riffle pool sequence. Geological Society of America Bulletin, 87(6), 883 890. Schirmer, M., Luster, J., Linde, N., Perona, P., Mitchell, E. A., Barry, D. A., ... & Radny, D. (2014). Morphological, hydrological, biogeochemical and ecological changes and challenges in river restoration the Thur River case study. Hydrology and Earth System Sciences, 18(ARTICLE), 2449 2462. Schwartz, John S., et al. "Restoring riffle pool structure in an incised, straightened urban stream channel using an ecohyd raulic modeling approach." Ecological Engineering 78 (2015): 112 126. Sear, D. A. (1996). Sediment transport processes in pool riffle sequences. Earth Surface Processes and Landforms, 21(3), 241 262. Sear, D., Newson, M., Hill, C., Old, J., & Branson, J. (2009). A method for applying fluvial geomorphology in support of catchment scale river restoration planning. Aquatic Conservation: Marine and Freshwater Ecosystems, 19(5), 506 519. Beland, J. (2004). NCAA board approves athletics reform. Academe, 90 (5), 13 . Schenk, E. R., Hupp, C. R., & Gellis, A. (2012). Sediment dynamics in the restored reach of the Kissimmee River Basin, Florida: a vast subtropical riparian wetland. River research and applications, 28(10), 1753 1767.

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60 Shapiro, A. E., Montalbano III, F., & Mager, D. (1982). Implications of construction of a flood control project upon bald eagle nesting activity. The Wilson Bulletin, 55 63. Shen, H. W., Tabios III, G., & Harder, J. A. (1994). Kissimmee River restoration study. Journal of Water Resources Planning and Management, 120(3), 330 349. Toth, L.A., 1990. Impacts of channelization on the Kissimmee River ecosystem. Proceedings of Kissimmee River restoration symposium, October 1988, South Florida Water Management Di strict, West Palm Beach, Florida, 47 56. Toth, L. A. (1995). Principles and guidelines for restoration of river/floodplain ecosystems Kissimmee River, Florida. Rehabilitating damaged ecosystems, 2, 49 73. Toth, L. A. (1996). Restoring the hydrogeomorphol ogy of the channelized Kissimmee River. River channel restoration: guiding principles for sustainable projects. John Wiley & Sons, Chichester, 369 383. Toth, L. A., Melvin, S. L., Arrington, D. A., & Chamberlain, J. (1998). Hydrologic manipulations of the channelized Kissimmee River: implications for restoration. BioScience, 48(9), 757 764. Toth, L.A., Koebel, Jr., J.W., Warne, A.G., Chamberlain, J., 200 2. Implications of Reestablishing Prolonged Flood Pulse Characteristics of the Kissimmee River and Floodplain Ecosystem. In: Middleton, B.A. (Ed.), Flood Pulsing in Wetlands: Restoring the Natural Hydrologic Balance, New York: John Wiley & Sons, Inc., 191 221. Toth, L. A. (1993). The ecological basis of the Kissimmee River restoration plan. Florida Scientist, 25 51. Warne, A. G., Toth, L. A., & White, W. A. (2000). Drainage basin scale geomorphic analysis to determine reference conditions for ecologic restoration Kissimmee River, Florida. Geological Society of America Bulletin, 112(6), 884 899. Whalen, P. J., Toth, L. A., Koebel, J. W., & Strayer, P. K. (2002). Kissimmee River restoration: a case study. Water Science and Technology, 45(11), 55 62. White, W. A. (1970). The geomorphology of the Florida Peninsula. Bureau of Geology Bulletin 51. Tallahassee: State of Florida Department of Natural Resources. Wohl, E. E., Vincent, K. R., & Merritts, D. J. (1993). Pool and riffle characteristics in relation to channel gradient. Geomorphology, 6(2), 99 110. Yang, C. T. (1971). Formation of riffles and pools. Water Resources Research, 7(6), 1567 1574.

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61 Zehetner, F., Lair, G. J., & Gerzabek, M. H. (2009). Rapid carbon accret ion and organic matter pool stabilization in riverine floodplain soils. Global Biogeochemical Cycles, 23(4). Zinger, J. A., Rhoads, B. L., & Best, J. L. (2011). Extreme sediment pulses generated by bend cutoffs along a large meandering river. Na ture Geoscience, 4(10), 675.

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62 BIOGRAPHICAL SKETCH After completing her m aster s, Megan Black will be a PhD student at the University of Florida studying hydrologic sciences. Born and raised in Florida, her education was driven by her love of the springs and rivers in the region. After several years of living in New York City and traveling the world on diffe rent career track, she returned to Gainesville to complete her studies. She graduated summa cum laude with her Bachelor of Science in 2016 and is completing her Master of Science in 2019 in geography from the University of Florida . She will be a graduate fellow at the UF Water Institute starting in Fall 2019 . executive director of a Gainesville based NGO called Current Problems, where she organized waterway cleanup efforts and related educational eve nt s . Megan spends her free time traversing the rivers of North Florida in her gheenoe with her golden retriever, Dutch.