C1 T S BLENCH HYDRAULICS LABORATORY, UNIVERSITY OF ALBERTA, EDMONTON

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1 Land and Water Australia Project JCU 15 Travelling Fellowship 2001, 2002 Ross Kapitzke Appendix C Agencies, people and sites visited in Canada Alberta & Ontario C1 T S BLENCH HYDRAULICS LABORATORY, UNIVERSITY OF ALBERTA, EDMONTON The T S Blench hydraulics laboratory in the Department of Civil and Environmental Engineering at the University of Alberta in Canada has a prominent history in river engineering, ice engineering, applied fluvial mechanics, computational hydraulics and other specialist fluvial research areas. The laboratory features strongly in fishway research (including culvert fishways in particular). The fishway work undertaken at the laboratory in the past 20 years has been largely directed by Professor (Emeritus) Rajaratnam and Dr Chris Katopodis (Department of Fisheries and Oceans Canada), both of whom accompanied me on my visit. The laboratory is equipped with experimental flumes to measure hydraulic conditions (eg. velocity, flow patterns, water surface profiles) in various fishway designs. The ichthyo-hydraulics flume examines the volitional swim behaviour of various fish species in near prototype conditions in hydraulic structures such as fishways, culverts and screens. Hydraulic laboratory studies provide essential information for fish passage design, particularly the relationships between water depths, velocities, flow patterns and other variables, which govern the effectiveness of fish passage facilities. Whereas mean values for discharge, depth and velocities in straight channels of simple cross sectional geometry can be estimated through application of standard hydraulic engineering methods, fish passage facilities involve complex flow characteristics not readily quantifiable without detailed hydraulic studies (Katopodis 1999). Hydraulic scale-modelling studies and field observations provide basic data on the characteristics of various fishway devices and contribute to an understanding of their performance. The basic principle for fishway research and development is to obtain a combined understanding of fishway hydraulics in the laboratory, volitional swimming ability and behaviour of fish under controlled conditions in the flume, and fish behaviour under variable conditions in the field. This requires close coordination and integration between the fish biology and engineering disciplines. Comprehensive physical modelling studies at the Blench Laboratory (aided by field observations) have produced basic hydraulic design information such as depth-discharge relationships and typical velocity profiles for pool and weir, vertical slot, Denil and pipe culvert (baffle) fishways. Fishways like this consist of sloping channel sections partitioned by weirs, baffles and vanes with openings for fish to swim through. They are distinguished by various arrangements of the inchannel devices or openings, which act hydraulically together to produce flow conditions that fish are able and willing to navigate. The different physical and hydraulic characteristics of each fishway type make them suitable for some fish species and not suitable for others. The culvert baffle fishways consist of sloping pipes flowing partly full with regularly spaced baffles or weirs on the bottom. Most baffle systems provide resting areas for fish in the cells or bays between the baffles, and control or barrier velocity conditions at baffles or slots. Fish are believed to use a combination of burst and prolonged swimming speeds to negotiate these barriers and pools. Rajaratnam and Katopodis performed a series of experimental studies on culvert fishways, using baffle designs in round corrugated steel pipe (CSP): namely the offset baffle (OB), spoiler baffle (SPB), slotted weir baffle (SWB), weir baffle (WB), Alberta fishweir (AFW) and fishbaffle (FB) systems (Ead, Rajaratnam and Katopodis 2002). The objective was to understand the hydraulics of these systems for various baffle heights and longitudinal baffle spacing, through analysis of the velocity field in the fishway, and the relationship between discharge and depth of flow. No recent studies have been conducted on fishways in box culvert structures, although McKinley and Webb (1956) trialled an offset baffle fishway in a box culvert. LWA Travelling Fellowship Ross Kapitzke Appendix C Canada - Alberta & Ontario academic\app c canada.doc 21/2/03 1

2 Laboratory studies, field observations, and practical application have led to the development of four basic approaches to culvert fishway design in Canadian streams - the plain culvert, hydraulic, stream simulation, and hybrid designs - as outlined below. Stream simulation or fish passage (hydraulic) devices are usually needed in road culverts, as plain culverts rarely provide conditions suited to fish swimming and passage capabilities, particularly for small fish. Water velocities in culverts are usually much higher and more uniform than those in natural channels, where stream meandering, pools and riffles, boulders and other substrate provide diverse patterns of slow or fast velocities longitudinally and laterally. Culvert velocities generally exceed sustained swimming speeds for fish (maintained for more than 30 min), but fish cannot maintain burst speeds (swim endurance < 20 sec) long enough to navigate the entire length of most culverts. In culverts with reasonably low flow velocities where no resting areas are available (plain culverts), the fish therefore attempt to use intermediate prolonged speeds for continuous passage through the culvert. Or they can use a burst and rest pattern to take advantage of low water velocities created by placement of large-scale roughness elements such as rip-rap, baffles, weirs or other forms of culvert fishways (hydraulic design). In virtually all of the above design options in Canadian streams, the culvert inverts are set below the grade of the streambed to maintain a minimum depth of flow suited to fish, and to reduce velocities through the structure. Plain culvert Hydraulic design Stream simulation Providing water velocities low enough for unassisted fish passage in plain culverts is a difficult task. In order for fish to negotiate the length of the culvert barrel without rest, culvert flow conditions must commonly be at the maximum end of the sustained swim speed range, or the lower end of the prolonged speed range. The maximum permissible culvert length for a particular maximum water velocity depends on the endurance time for which the target fish size and species, can travel at or above that velocity. Designing plain culverts to meet restrictive velocity criteria is frequently not practical or economical, particularly for weak swimmers migrating during periods of high stream flow. Where the plain culvert fishway design is used, the common approach is to provide mean culvert velocities of less than 0.9 m/s at or below the fish migration discharge, to concentrate low flows, and to secure at least 200 mm water depth through the culvert. In the hydraulic design, arrangements of baffles in the form of plates, blocks, sills etc. are attached to the culvert base to enhance fish passage. Velocities less than the fish burst speed at the baffles, and lower velocities at intermediate resting areas, are intended to allow fish to use a burst-rest swim pattern to advance through the culvert in stages. The advantage of the baffle culvert design over plain culverts is that it leads to culverts of smaller size and steeper slope. A limiting slope of 5 % in circular or elliptical culverts, with a minimum culvert diameter or rise of 2.5 m is recommended. A minimum baffle height of 300 mm is preferred, with a minimum 200 mm water depth during low flows. The principle of the stream simulation or nature-mimicking approach is to pattern the fishway after streams bearing similar species, and to preserve natural stream characteristics through the culvert for biologically significant discharges. The stream simulation concept uses stream dimensions to size the culvert, and large rip-rap within the culvert barrel to resemble passable natural rapids. The preferred culvert size is sufficient to maintain the average stream width and cross sectional area for the fish migration discharge. The culvert is set at the average stream slope for the site, placed below the stream bed, and filled to stream grade with non-uniformly laid rip-rap - large enough to be stable during the design discharge. The stream simulation approach may be more economical than plain culvert designs where large cross section areas are needed to maintain acceptable water velocities for fish passage. Long or undersized culverts will inherently depart from natural conditions and approach the plain culvert situation, whereas bridges and arch culverts supported by footings allow the retention of natural stream properties at the crossing and do not normally hinder fish migration unless significant channel constriction occurs. The stream simulation approach approximates stream morphological features, and places considerable emphasis on retaining as many qualities of the LWA Travelling Fellowship Ross Kapitzke Appendix C Canada - Alberta & Ontario academic\app c canada.doc 21/2/03 2

3 original stream channel as possible Hybrid - Roughened bed Hybrid designs are a cross over between the hydraulic design and the nature design. In the hybrid structures, a hydraulic design approach to minimising waterway size is adopted, but riprap is placed as roughening in the culvert barrel instead of using formal baffle structures such as steel plates. This represents a partial natural channel design, but because it is not designed to simulate the natural adjoining channel, the culvert waterway is not as effective as the natural stream, and should be treated as a baffled structure. Hydraulic conditions are inferior to the stream simulation approach, where diversity in flow conditions and low velocities are achieved. Although the hybrid design provides more natural substrate than the artificial baffle structure, the rocks are not as effective hydraulically, and velocity conditions and flow patterns cannot be readily predicted. Fixing rocks to the culvert base is problematic structurally, and quality control in construction is an issue. C2 DEPARTMENT OF FISHERIES AND OCEANS CANADA (DFO), PRAIRIES AREA In a three-day field trip of the Rocky Mountain area, I was able to inspect and discuss waterways, fish passage barriers, culvert fishways and habitat restoration sites and issues with officers from the Department of Fisheries and Oceans Canada (DFO). DFO is responsible for administering the Fisheries Act, federal fisheries legislation that strongly supports policies of no net loss of fish habitat, and protection of fish passage. This federal agency, which has historically had a prominent role on the Pacific and Atlantic coasts of Canada, with a focus on salmon, has recently expanded its role and presence in the Prairie Provinces of Alberta, Saskatchewan etc. The habitat engineers and a fisheries biologist who I traveled with have roles in several provinces relating to the research, design and regulation of culvert fishways at major highway waterway crossings. During the trip, we saw and/or discussed examples of fish migration problems, and applications of the various culvert fishway types: plain pipe culvert; hydraulic (baffled) culvert of various types; stream simulation; and hybrid designs (rock in culvert bed). Design considerations and criteria for culvert fishways were examined, including particular design features relating to the culvert bed, inlet and outlet channels etc. Some comparisons were made between fish migration characteristics, fish passage barriers, design approaches and culvert fishway solutions for Canada and USA (eg. Washington State). I was able to consider the suitability of transferring this technology to Australian conditions, and to explore the integrated biological and engineering approach to design. Culverts used to convey water under road embankments in Canada are typically circular, although elliptical, rectangular, or pipe-arch shapes are also used. Culvert diameters can vary from a fraction of a metre to several metres, and culvert slope can vary generally from zero to about 5%. Culvert lengths are commonly about 30 m, but lengths exceeding 100 m are not uncommon. The typical road culvert fishway visited on the field trip was a single barrel corrugated steel pipe (CSP) culvert under a high embankment fill, with a lowered bed countersunk barrel design, and a hydraulic fishway design using baffles. The large diameter single barrel culvert is preferred in upland streams in the steep mountain country; in order to minimise obstruction to ice flow and to provide a single fishway for the total waterway. The culvert invert is set below the streambed by approximately 20% of the culvert diameter (with a minimum of 300mm), thereby addressing many problems for fish by reducing culvert velocities, providing favourable entry and exit conditions, and maintaining a minimum water depth for swimming. A great deal of attention is given to rehabilitating the effects of the culvert and associated channelisation and realignment for the complete stream reach within the road corridor. Protection works are provided at the culvert inlet and outlet to transition from the normal streambed into the lowered bed in the culvert barrel. This usually includes a rock ramp tailwater control, downstream LWA Travelling Fellowship Ross Kapitzke Appendix C Canada - Alberta & Ontario academic\app c canada.doc 21/2/03 3

4 of the outlet, to pond water over the most downstream set of baffles in the pipe. Habitat restoration and stream stability techniques, including channel form modifications, rock protection and revegetation, are applied in the inlet and outlet channel connections from the culvert to the edge of the corridor. Although nature-like or stream simulation culvert fishway designs have not been used extensively in recent applications in the Prairie Provinces, a version of this culvert fishway type was used on the Liard Highway project in the North-west Territories during the 1980s. Rock weirs were used in the barrel to create a pool and riffle sequence of flows to simulate the natural stream, and to provide suitable passage conditions and habitat for a wide variety of species. Nature-like fishways such as this simulate the dynamic stream behaviour, and are expected to preserve their structural integrity at high to moderate floods, ice and debris events, but not necessarily during extreme events. Adoption of nature-like fishways such as stream simulation designs in culverts, and rock ramp and bypass fishways in stream channels, reflects a shift towards an ecosystem approach for fish migration and fish habitat management. Conventional fishways, including the hydraulic baffle designs for culvert fishways, usually target particular species, and may be less suited for small species, juveniles, and very large fish due to velocity, turbulence and space limitations. Nevertheless, baffle culvert fishways are commonly less expensive than the stream simulation designs, and can be used to retrofit existing culvert barriers in situations that would require complete removal and replacement using the nature-like approach. Although there may be reluctance for the hydraulic design approach and the selection of only target fish species and migration periods, it is not practical to provide for the full range of species and flow conditions in all circumstances. Furthermore, baffle culvert fishways do not need to be restricted to the classical North American adult anadromous high speed, high jumping species such as salmon. A wide range of sizes and species are present in Canadian prairie streams, and designs there are now providing for species with a swimming capacity as low as 0.5 m/s. Irrespective of whether the stream simulation or hydraulic design approach is used, a certain amount of stream hydrology and hydraulic evaluation is required for culvert fishway design. Although it is desirable that fish are free to move upstream of a barrier at all times, there are critical periods such as during spawning migration, when delay is most damaging to the fish. The Canadian practice is to evaluate the hydrological regime so that fishways provide suitable passage conditions at various biologically significant river flows. High and low discharge conditions are considered, to accommodate movements of various species inhabiting the river system, and appropriate fishway hydraulics are assessed for a range of river discharges and corresponding water levels, to ensure suitable hydraulic conditions such as depth, velocity and level of turbulence for these species. The fish migration discharge (maximum discharge allowing particular species to traverse the culvert) is estimated using flood frequency analysis in particular locations, but normally a default design flow of the 3-day, 10-year ARI discharge is used. This flow is based on maximum allowable delays for spawning fish moving upstream, and corresponds to the stream discharge that is exceeded for no more than 3 days in the 10 year ARI flood. Notwithstanding the history of fish passage research and application of various culvert fishway designs in Canada, much more needs to be done in the field. The development of design criteria for effective fishways depends on the integration of findings from studies on fish biomechanics and fishway hydraulics, and the field assessment of fishways. More work is required to optimise culvert fish passage design, particularly with non-salmonids and juveniles. Whereas provision for fish passage represents a significant element in road culvert design in fish bearing streams in Canada, it is hardly considered at present in Australia. Nevertheless, fish passage provision at road drainage structures may not represent as significant a proportion of total costs for an Australian road project as one would first think. Due to extensive drainage LWA Travelling Fellowship Ross Kapitzke Appendix C Canada - Alberta & Ontario academic\app c canada.doc 21/2/03 4

5 requirements, drainage crossing costs in many parts of Australia represent a large proportion of total road costs (probably more than in Canada). If low cost fish passage facilities can be developed for these relatively expensive drainage structures, provision for fish passage is likely to only marginally increase drainage infrastructure and overall road infrastructure costs. Plate C1: Pipe culvert without fish passage inlet Plate C2: Pipe culvert without fish passage outlet Plate C3: Culvert inlet channel Plate C4: Culvert outlet channel Plate C5: Culvert inlet drainage Plate C6: Culvert inlet with ice Plate C7: Double barrel culvert outlet with recessed base Plate C8: Double barrel culvert inlet channel LWA Travelling Fellowship Ross Kapitzke Appendix C Canada - Alberta & Ontario academic\app c canada.doc 21/2/03 5

6 Plate C9: Corrugated steel pipe with baffles Plate C10: Corrugated steel pipe with spoiler baffles C3 DEPARTMENT OF FISHERIES AND OCEANS CANADA, GREAT LAKES AREA The Department of Fisheries and Oceans (DFO) Great Lakes area is endeavouring to develop a policy and protocol for fish passage remediation at road culverts to cater with the myriad of applications for permits for culvert fish passage structures, which are assessed by DFO in cooperation with regional conservation authorities. DFO have attempted to address a number of these issues in a review of best practice fish passage design approaches and techniques for road culverts. Their approach is to reconcile the technical fish passage literature produced by Katopodis and others, with the requirements of clients ranging from landholders to major agencies, for fish passage facilities ranging from basic culverts to major crossings. C4 UNIVERSITY OF GUELPH, DEPARTMENT OF GEOGRAPHY Stream restoration activities in Ontario are handled by a number of agencies at the provincial level (Ministry of Natural Resources), regional level (eg. Credit Valley Conservation Authority), and the local authority level (eg. City of Toronto Council). The Ministry of Natural Resources (MNR) has overall responsibilities for administering waterway related legislation in the province of Ontario, and shares administrative responsibilities for some federal legislation with the Department of Fisheries and Oceans Canada. Conservation authorities such as the Credit Valley Conservation Authority (CVCA) have responsibilities for regional planning and development, including whole of catchment management and stream restoration. City and regional municipalities such as the City of Toronto council are involved in streams through the effects of public works infrastructure, eg. drainage works, road and water facilities. Consultants and researchers at institutions such as the University of Guelph are involved in stream restoration planning and design, and research and development into stream behaviour and restoration approaches. Ontario is renowned for its stream management successes through agencies such as the Grand, Credit Valley, and Toronto Regional Conservation Authorities. A multidisciplinary approach is taken, involving water resources engineers, civil and structural engineers, environmental planners, fisheries biologists, terrestrial and wetland biologists, and others. The Ministry of Natural Resources, in association with numerous other agencies and individuals, has prepared a Natural Channel Design manual (soon to be released) to facilitate interdisciplinary planning and design for sustainable stream restoration. Nevertheless stream researchers and practitioners are still calling for more attention to strategic management, evaluation of broader scale stream processes, and application of restoration practices that are sympathetic to dynamic stream behaviour, rather than mere prescriptive solutions to local problems. LWA Travelling Fellowship Ross Kapitzke Appendix C Canada - Alberta & Ontario academic\app c canada.doc 21/2/03 6

7 According to Dr John Beebe from the Department of Geography at the University of Guelph, stream managers and practitioners commonly fail to satisfactorily incorporate geomorphic studies and understanding into stream management and stream restoration practices. Rosgen's stream classification system for natural channel design (NCD) is used extensively, sometimes leading to problems through misapplication. Disseminated through short courses on geomorphology for nongeomorphologist practitioners, this system categorises stream types in bands, and may be inappropriately applied by some practitioners in a manner akin to a biological classification system. Although providing a systematic framework for defining stream types and examining restoration approaches, the Rosgen NCD classification system is often inadequate as it is not process based, and may over-simplify stream type and behaviour. Key geomorphic parameters are often ignored in this system, which tends to emphasise stability rather than to recognise natural stream processes and provide for a dynamic system. For example, an incorrect classification of channel type for a channel restoration project on Little Etobicoke Creek led to further stream degradation before reassessment and further restoration was undertaken. The initial design prescribed a larger than appropriate bankfull flow magnitude on the basis of hydrological modelling, without site measurements to establish a channel cross section from a stream template. The interconnection of the stream channel with its floodplain had been neglected in the initial classification of channel type, with the result that the stream channel eroded out. Following further remediation, the channel has been progressively readjusting its stability. In spite of its successes, the Ontario stream restoration industry of government agencies, consultants and researchers would benefit from documented practices for integrated channel design that adequately incorporates interdisciplinary studies, including stream geomorphology. This would assist practitioners and managers with proactive management that takes account of natural stream processes, rather than following conventional rehabilitation practices that may merely react to problems. The new Natural Channel Design manual, developed by the Ministry of Natural Resources and others, will help in this regard. Plate C11: Little Etobicoke Creek restoration (Source: projdetail.asp?no=136) Plate C12: Harsh river improvement practices in Etobicoke region, Ontario (Source: structures_4.htm) LWA Travelling Fellowship Ross Kapitzke Appendix C Canada - Alberta & Ontario academic\app c canada.doc 21/2/03 7