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Presentation Abstracts(alphabetical by presenter)Click on a title below to view the abstract for each presentation. Vane Structures Used in Natural Channel Design Applying Natural Stream Restoration Design Concepts to Urban Streams: What makes a project successful? Plant Material Applications in Natural Channel Design Nippersink Creek Restoration Bear Run Stream Restoration: A Case Study Utilizing Natural Channel Design Concepts Channel Recovery in Little Darby Creek With Dam Removal Case Study Comparisons of Natural Channel Design: Design\Build Utilizing Priorities 1-4 Geomorphic Assessment: What is it and why is it Important? Data Requirements & Steps For NCD Projects: An Overview of the "Guidelines for Natural Stream Channel Design in Pennsylvania" Stream Assessment and Restoration in Baltimore County, Maryland: Critical Components of Integrated Watershed Management Ecosystem Restoration of Woodiebrook Big Darby Floodplain Restoration Using Levee Setback and Conservation Easements Bankfull Characteristics of Ohio’s Streams and Their Relation to Peak Streamflows Investigating the Application of Natural Channel Design to Agricultural Ditches Vane Structures Used in Natural Channel Design From blockstone weirs to log-vane J-Hook combos, the design and construction of vane structures used in natural channel design projects have progressed from laboratory flumes to field applications with excellent results in controlling the channel stability, flow and sediment rating curves for reconstructed streams. Vane construction is now commonplace in channel designs across the United States and in England. Dave Rosgen, P.H., recently published a comprehensive design guide for cross-vanes, w-weirs and j-hook vane structures. Excerpts from this resource will be discussed as the basis for proper design considerations. In addition, this discussion includes design considerations and construction techniques in smaller streams, sand-bed streams and intermittent streams. One-dimensional and two-dimensional hydraulic modeling applications demonstrating velocity and shear stress control for bank stability, grade control and bridge scour countermeasures will also be discussed. Applying Natural Stream Restoration Design Concepts to Urban Streams: What makes a project successful? Urban stream restoration using natural channel design principles is gaining in popularity throughout North America and in Ohio. The process of restoring a totally natural channel is complex and difficult at best, and many times outright impossible. Streams are dynamic living ecosystems that often defy our best attempts to tinker with them. However, over the last ten years many design professionals have begun to apply natural channel design principles to projects without much formal training in fluvial geomorphology and aquatic ecology, or more importantly, valuable field experience. It appears that many project designs rely on a snapshot of current stream conditions without exploring the processes that brought the stream to the condition that it is today, and more significantly, the processes that the stream will undergo when restored. Additionally, many techniques being used today tend to originate from one source, without modification for local conditions. Using case studies of recent urban stream restoration projects that have employed various natural channel design principles, I will review ways in which to integrate natural processes and variability in natural design. I will also present both project successes and failures and offer suggestions for ensuring success in future projects.
Plant Material Applications in Natural Channel Design Plant Materials selected as stabilization components in channel designs have often only involved low growing grasses with shallow root depths. Although grasses perform well in some channel situations other plant species should be considered. Diverse vegetation and the vegetative techniques at the time of installation establish the foundation for a diverse, manageable and functioning stream corridor. The existence of woody plant species is considered desirable in many natural channels. The installation of woody plant materials into a designed channel project often meets with some resistance because of the time of installation. Many streambank stabilization projects are done in the dormant season for plants using live dormant plant parts in many different soil bioengineering techniques. In an effort to extend the installation period of the brush layer technique the Rose Lake Plant Materials Center established a trial technique to grow brush layers in the greenhouse and then install a rooted brush layer outside of the dormant season. Brush Layer Boxes were designed built and planted resulting in rooted brush layers ready for field installation. This technique of having pre-rooted brush layer materials allows for installation outside of the dormant season. A Live Crib Wall is another technique utilizing plants as a major stabilization component. Crib walls can be constructed using many man made as well as natural materials. It was decided to use a live cribwall and slope grid installation on a 30-foot high severely eroded stream bank along the Red Cedar River in Okemos, MI. Robinia pseudoacacia L. (Black Locust) was the species selected for the cribwall construction because it grows extremely straight and is very rot resistant. The cribwall and slope grid were constructed entirely by hand and planted with native plants. Non native willows were used because of they lack invasive characteristics compared to native willows. The installation was a low impact installation. It is being evaluated and the results are impressive after an above normal high water spring flooding of the site and the hot dry summer growing season. Some fill material has flowed from the slope grid and will be replaced this fall at which time more willows will be replaced, during the dormant season. The live cribwall and slope grid are viable alternatives for many stream bank stabilization areas.
Nippersink Creek Restoration The McHenry County Conservation District is a publicly funded open space agency charged with land protection in McHenry County, the nation's most rapidly growing county, located 65 miles NW of the Chicago Metro area. The agency's written land management policy mandates the restoration of its holdings to pre Euro/American settlement conditions whenever possible. During the summers of 1999 and 2000 agency staff dechannelized 3.2 miles of Nippersink Creek, a fourth order stream located within the boundaries of Glacial Park, MCCD's largest site at 3,000 acres. The stream, straightened for agricultural purposes in 1951 had suffered serious bank erosion problems, loss of in stream habitat diversity, and disconnection from surrounding floodplain wetlands. This session will chronicle the successes and failures of the project based on a two years of accumulated data. Topics covered will include channel design, equipment selection and use (what works and doesn’t) of planting practices, erosion control and recovery of the stream biota since the completion of the project. Bear Run Stream Restoration: A Case Study Utilizing Natural Channel Design Concepts Presented by: Design by: Daniel E. Mecklenburg A small tributary (d.a. .2 sq.mi.) of Bear Run was relocated to alleviate flooding caused by excessive sediment load and aggradation dating back to the 1930’s. The stream, a Type D5 on USFS land, had formed an alluvial fan, which had become higher than an adjacent private home. A road and roadside ditch dissected the toe of the alluvial fan, intercepting the channel and routing it approximately 300 feet to Bear Run. Additional project goals were improved habitat quality and demonstration of a natural channel design. A parallel design procedure was employed: one based on mimicking a reference reach, the other calculating sediment transport competence. The reference reach procedure started with identifying a stable stream reach immediately upstream from the project, then surveying its cross sectional dimension, longitudinal profile, meander pattern and channel material. This data was then converted to dimensionless ratios to allow for comparison with published values. The procedure used to check sediment transport competence was simply to meet the criteria of having the bedload supplied by the watershed move at the threshold of motion at bankful flow. Both design tracks were satisfied by constructing two channel types alternating between steep (7%) step-pool reaches (Type A2) and lower gradient (1%) self-maintaining Type E4 reaches. To date no flooding has occurred and preliminary monitoring of fish and riparian vegetation has yielded encouraging results.
Channel Recovery in Little Darby Creek With Dam Removal ODNR, Division of Natural Areas and Preserves In 1990 the Columbus/Franklin County Metropolitan Park District removed the only low head dam from the Little Darby Creek State and National Scenic River. This structure was located in Georgesville, Ohio just above the confluence of the Big and Little Darby Creeks. The 200 foot long by 10 foot high structure impounded water for almost a mile on the Little Darby. Since the structures removal the Little Darby has been working to regain its natural channel characteristics in this section by downcutting into depositional sediments, redeveloping meanders, riffles, runs and pools. Measurements were taken to determine the channel’s dimension pattern and profile within the previously impounded area as well as on un-impounded upsteam segments. Measurements were used to compare the two channels and to evaluate the degree of recovery that has occurred to date.
LandStudies, Inc. The extent and value of natural resources, time, money, and permitting requirements differ among the four types of stream restoration (Priority 1-4) a practitioner selects in a Natural Channel Design Project. This presentation will differentiate the four priority levels of stream restoration and provide a detailed summary of each priority using case studies.
Buck Engineering PC Geomorphic assessment is the study of a landform’s physical characteristics. In relation to stream restoration, geomorphic assessment is essential to answer questions about the existing condition, stability, and restoration opportunities of the channel and its floodplain. Stream stability is defined as the ability of a channel to carry the water and sediment delivered by its watershed, such that over time it maintains its dimension, pattern, and profile, while neither degrading nor aggrading. Assessments using existing databases and field measurements are used to determine stream stability problems, their causes, potential solutions, and the effectiveness of restoration projects following completion. For a given study stream, assessments should be conducted at multiple scales: river basin, watershed, project site, and stream reach. At the river basin scale, the assessment should include geology, soils, land use, land cover, and water quality problems and sources. This information helps determine the river’s overall condition and the expected optimal condition of the study stream. At the watershed scale, similar information should be collected in greater detail. In addition, the hydrologic response of the watershed to various rainfall amounts is important in determining the appropriate size and shape of the stream channel and floodplain. Regional hydraulic geometry relationships determined for various watershed conditions are valuable in more detailed assessments. At the project site scale, information on valley type, drainage network, ground water, detailed soil conditions, riparian condition, adjacent land uses, and water quality problems is used to understand the hydrology and restoration potential for the study stream. Finally, the stream reach scale assessment is used to determine existing condition, channel evolution stage, restoration options, and project success following completion. Detailed data on bankfull channel dimension, pattern, and profile, in addition to bed material, are necessary to complete this assessment. My experience indicates that a stream restoration project will be successful if the project team conducts careful assessments before, during, and after the project. Successful project teams include biologists, hydrologists, and engineers who understand natural stream functions. Successful teams make the effort to evaluate reference streams in planning and designing restoration projects, and they consider multiple alternatives before deciding on the best approach for a given stream project. Most importantly, successful stream restoration requires that we all learn from past mistakes and avoid repeating them.
Bradford Co. Conservation District As an outgrowth of the First Natural Stream Design Summit held in PA in February of 2000 the Pennsylvania Keystone Stream Team identified a number of challenges with regard to stream restoration permitting, data management, design and implementation, problem identification, success criteria, and education. As a result of the evaluation of these challenges, the development of a set of design guidelines for professionals was considered a top priority. It is the purpose of these guidelines to provide a common process for planning, designing, and evaluating natural stream channel restoration projects. These guidelines, currently in draft format, are intended to open communication, facilitate the exchange of inter-agency information, and build consistency in natural stream channel designs, so that restoration projects can proceed without the glitches and flaws that can waste enormous amounts of time and money. The “guideline” address the areas of assessment, working with the watershed community, full site assessment, permitting, final design, construction considerations, monitoring, qualifications of designers and contractors, and appendices on case studies and data sources.
Dept of Environmental Protection and Resource Management The protection and restoration of Baltimore County’s 2,100 miles of streams and rivers are central themes of the County’s environmental management efforts. Stable streams contribute to high-quality beneficial uses such as the Baltimore region’s drinking water supply, the abundance and diversity of aquatic resources, and the aesthetic and recreational needs of viable urban communities. However, throughout the one-third of Baltimore County that lies within its urban growth boundary, many streams have become degraded and unstable, resulting in accelerated erosion, poor water quality, extensive riparian property losses, and damage to public infrastructure such as sewers. The cause of stream instability is primarily hydrologic alterations associated with land development, especially prior to the 1980’s, that occurred without environmental protections such as stormwater management, stream buffers, and forest conservation. Stream restoration is a critical component of the County’s Integrated Watershed Management Program, developed by the Department of Environmental Protection and Resource Management (DEPRM) to address Federal and State non-point source pollution control mandates, initiatives for restoration of the Chesapeake Bay, and local environmental and growth management priorities. The IWMP is implemented County-wide; however, its focus is on the urbanized watersheds wherein economic, social, and environmental systems most critically define the quality of life for County citizens. The IWMP is a set of functional programs including: (1) growth management and land conservation; (2) resource protection; (3) restoration; (4) facility maintenance; (5) water quality monitoring; (6) program coordination, watershed planning and research; and (7) education and citizen participation. Baltimore County's programs have been recognized by the Chesapeake Bay Program and the National Association of Counties. Since 1987 DEPRM has implemented a Capital Improvement Program for the design and construction of watershed restoration projects, including stormwater conversions and retrofits, stream restoration, shore erosion control, waterway dredging, and reforestation. DEPRM’s restoration program is based in concept on emulating natural ecosystem functions. The CIP is structured by watershed accounts, and projects are prioritized based in part on watershed management plans. General Obligation Bonds and State cost-share programs primarily fund projects. DEPRM’s stream restoration projects are typically selected from priorities identified through watershed management plans. These plans include characterization of existing watershed conditions, establishment of restoration objectives, identification of restoration options, and evaluation of implementation feasibility. Specific characterization studies include pollutant loading analyses for existing and future land uses based on the Storm Water Management Model (SWMM) and stream stability analyses based on Rosgen methods. More than 700 miles of County stream have been geomorphically assessed at some level. Watershed management plans have been completed for 9 of the County’s 14 major watersheds, at a total cost of more than $1.7 million. DEPRM manages contracts with environmental consulting firms for the preparation of each plan. Restoration projects recommended in the plans are prioritized for design and construction through the Capital Improvement Program. The County’s stream restoration projects now include multi-year monitoring programs in order to assess the effectiveness of restoration projects with regard to geomorphic stability, water quality, and aquatic habitat. An example of Baltimore County’s stream restoration projects is the Spring Branch Stream Restoration and Stormwater Retrofit Project, completed in Spring 1997, which included the reconstruction of approximately 10,000 feet of continuous stream channel, the creation of a multi-cell stormwater management pond, and the stabilization of numerous storm drain outfalls. This $ 2.43 million project involved the removal of deteriorating concrete channels and reconstruction of a stable channel form using boulders and root wads to recreate step pools and meanders for stream stability and velocity control. The project successfully reduced erosion and nutrient pollution of a sub-watershed of the Loch Raven Reservoir, and it improved conditions in the riparian interface for a moderate-density residential community, including the protection of exposed, failing sewers. Baltimore County’s experience has demonstrated that stream restoration can contribute to objectives for restoring and maintaining the physical, chemical, and biological integrity of water resources. Conducted in conjunction with other County programs and services, and implemented within a watershed framework, stream restoration is an important tool for environmental management.
Oxbow River & Stream Restoration, Inc. Woodiebrook is a small cold water tributary in the headwaters of the Chagrin River in Geauga County, Ohio. Residential development resulted in a significant impact to over 3000 LF of channel including the channelization of the western tributary and the impoundment of the eastern tributary. The restoration goals of the project were to restore the ecosystem and previous natural characteristics of Woodiebrook. The goals included the development of a mitigation and monitoring plan, the formation of an advisory council, the purchase of the Woodiebrook stream corridor and negotiation of conservation easements outside of the project area and finally after restoration, the reintroduction of rare native brook trout. The restoration of Woodiebrook provides examples of important design and construction considerations in restoring the function of headwater streams. Distinguishing project characteristics include the considerations to restore ground water interaction, substrate composition and in-stream habitat features, valley and channel morphology, methods used to reduce soil compaction, mass vegetation techniques and reintroduction of organic debris.
Big Darby Floodplain Restoration Using Levee Setback and Conservation Easements Randy Sanders - Program Administrator Similar to many other Ohio streams, the mainstem channel and riparian habitats of Big Darby Creek have been hydrologically modified by the construction of levees to contain short-term flooding. As a result, meander patterns and channel stability have not been allowed to naturally develop and many landowners experience bank erosion of levee walls. Using a “streamway concept”, approximately one mile of the lower mainstem and adjacent floodplain of Big Darby Creek was restored through levee setback and perpetual conservation easements to allow for natural meander development and succession of riparian forests. The distance of levee setback was determined by a variety of factors such as historical rates of erosion based on aerial photographs, the calculation of channel belt width for a fully developed meander pattern, existing landuses. The project benefited the landowner by providing economic and technical assistance to solve an ongoing problem and the stream by restoring more floodplain and space for the meanders of Big Darby Creek to laterally migrate through time. The project was funded and implemented through a broad based partnership between a private riparian landowner and staff from the U.S. Fish and Wildlife, U.S. Department of Agriculture, Ohio Department of Natural Resources (multiple Divisions), and Pickaway County Soil and Water Conservation District. With the majority of Ohio’s stream miles flowing through private property, projects like this are becoming increasingly important for the conservation and restoration of streams and riparian habitats throughout the state.
U.S. Geological Survey Under natural conditions, streams will display geomorphic characteristics that are ultimately governed by a balance of energy associated with fluvial erosion, transport, and deposition of sediments. Spatially varying factors such as topography, climate, and bank- and bed-material composition affect the energy balance and consequently lead to spatial variation in geomorphic form. Many of these same factors also affect peak streamflow characteristics and so there is frequently a strong relation between peak streamflows and stream geomorphic characteristics. One geomorphic characteristic that is commonly of interest is the bankfull stage, which is the stage at which a stream first begins to overflow its natural banks. In addition to its obvious importance from a flood awareness standpoint, the bankfull stage is also important from a geomorphic standpoint because flows at or near bankfull stage tend to move the most sediment over the long term, and consequently are very important in forming the channel (Wolman and Miller, 1960). Construction of highways frequently involves crossing streams and rivers. In the past, the design of hydraulic structures such as culverts and bridges was based predominately on their hydraulic characteristics. Attention to the geomorphic consequences of these structures was mostly focused on assuring the stability of the structures. Increased environmental awareness has led to an expanded focus that extends the concern for geomorphic consequences appreciably upstream and downstream of the structures. In order to better address that expanded focus, it is necessary to improve our understanding of the relationship between stream geomorphic characteristics, such as bankfull stage, and the physical, geological, and meteorological conditions that influence them.
Department of Food, Agricultural and Biological Engineering Highly modified channels drain extensive portions of the U.S.A. In these productive agricultural areas, most natural channels have been deepened and straightened to facilitate the flow of water from agricultural subsurface drainage outlets and to maximize conveyance. Habitat modification, largely related to drainage improvement, is now the leading cause of aquatic life use impairment in Ohio. Maintenance practices remove or kill vegetation and typically deposited sediment is excavated out of the ditches periodically. Short-term benefits due to improved conveyance are often offset by cycles of bank failures, accelerated scours, and the need to place rip-rap along the toe of the embankments. Results will be presented of a study that is evaluating the usefulness of considering fluvial processes in the design and maintenance of agricultural drainage ditches. Drainage ditch form (pattern, profile, and dimension) has been measured on ditches in the Portage River Watershed, Ohio. Regression techniques were used to relate these properties to drainage area, channel slope, ditch width, and bed material particle size. A statistical analysis of precipitation data and regional stream discharges was used to determine the frequency of events associated with the formation of a small meandering main channel within the confines of the ditch, as well as benches, small floodplains, riffles and pools. The dominant main channel and benches are formed by flows that occur more frequently than discharges associated with natural channels. This new knowledge of fluvial processes in drainage ditches is going to be used to modify ditch design and maintenance practices in order to make the ditches more self-maintaining and to enhance the ecology of these systems. |
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