River Record Sheet User Guide
Contents
1. Morphology example morphological units are given in the table below to help define the appropriate features within the reach Morphology ai a an Pool deeper sections of river less Plane bed invariant bed and flow type energetic flows shallow gradient finer bed often gravels and some cobbles shallower material than riffles than pools River Record Sheets User Guide Riffle shallower sections of river energetic flows moderate gradient coarser bed material gravels 4 ad eu Boulder step boulder bed material steep gradient energetic turbulent flows Island created through bifurcating flow around a stabilised section of bank well vegetated mixed sediment composition Rapid steep gradient coarse bed material cobbles possibly small boulders energetic turbulent flows Le i Transverse bar Extension of lateral side bar towards the centre of the channel composed of cobbles gravels or fines channel mixed sediment composition River Record Sheets User Guide r es x i Point bar deposition on inside of bend Mid channel bar deposition in the centre of associated to bank erosion on opposite the channel becomes stabilised through bank composed cobbles gravels and fines infilling and vegetative colonisation mixed sediment composition Confluence bar deposition at confluence of Chute channel cut through a bar deposit two watercourses often creating a splay c2. River Setting and Influences Page 2 The reach start point finish point and overall reach length are noted at the top of the page Box 1 The River and Valley Setting are described through ticking the appropriate box examples in tables below Terraine D F ama Low Hills Lowland River Record Sheets User Guide BA consulting Drift Type gt ere del te Moraine S ren coverage of Fluvio glacial significant coverage of unconsolidated glacial debris soil and rock layered soil and rock Fluvial significant coverage of reworked Lake significant coverage of lake deposits fluvial deposits rock soil gravels River Record Sheets User Guide Valley Type vee ea ger ea Dra f h PR yee Fr Wide floodplain River Record Sheets User Guide River Type Bedrock often upland a Step pool large boulder groups forming sediment steep channel gradient stable steps separated by pools pools contain finer channels sediment steep channel gradient stable channels Plane bed gravel cobble beds armoured Braided Often relatively high gradients bed relatively stable channels often straight high bedload channel characterised by planform number of threads highly dynamic but usually during larger floods River Record Sheets User Guide en De Wandering characteristics of braided and Active single thread meandering sand active meandering smaller be
3. of the particular study reach 14 River Record Sheets User Guide Riparian Vegetation Character Page 4 Box 6 This describes the riparian vegetation over the left bank right bank and on any in channel islands bar or berms A photographic record is also recommended for conclusions drawn in this section The options are 1 Bare little to no vegetation a potential indicator of grazing pressures or active banks in channel deposits Sparse annual grasses some low growing vegetation may be subject to grazing pressures Dense annual grasses providing some significant stabilisation to the banks or in channel feature Mixed scrub greater stabilisation provided by root networks Scrub trees significant root networks provide strong stabilisation to the banks or in channel feature Plantation unnatural planting of scrub and trees Single line a single row of scrub or trees lining the banks Narrow belt 2 to 4 rows of scrub or trees Wide belt Greater than 4 rows of scrub or trees 15 River Record Sheets User Guide meetin Geometry Quantification Page 5 This page provides a means to record important quantitative measures of the river reach that can be tabulated and compared to following subsequent audits post project appraisal Numerous copies of this page can be made to record a suitable amount of detail for your reach depending on the reach length The parameters than can be
4. surface surface disruption disruption Bed and Bank Activity the movement of the channel bed is characterised in this section as well as any evidence of bank erosion failing or stabilisation with the following options 1 Stable bed bedrock or boulder dominated infilled consolidated gravels consolidated cohesive bed 2 Mobile fines unconsolidated fine sediment e g sand and silts could be characterised by ripples dunes 3 Mobile gravels clean gravels on bar features look for fresh gravel deposits 4 Mobile bed general mobile bed little fine sediment infilling recent evidence of movement 5 Armoured bed coarse bed material creates a protective layer across an unconsolidated bed providing some stability at moderate flows 6 Active bars evidence of clean gravel deposits on bar features little vegetative colonisation 7 Inactive bars heaving fine sediment infilling of gravel bar features well vegetated 12 River Record Sheets User Guide ent ee 8 Outer bank erosion fluvial erosion of the outer bank which could trigger bank collapse 9 Inner bank erosion fluvial erosion of the inner bank 10 Erosion of both banks 11 Shoaling riffle develooment is there significant accumulation of gravels on the channel bed that is creating shallower rippled flow 12 Bar island creation has in channel deposition created bars or islands 13 Bar island bank erosion is there evide
5. River Record Sheets User Guide ere River Record Sheet User Guide This user guide is intended to provide information to enable the River Record sheet to be completed as part of post project appraisal and river reconnaissance studies It has been adapted from Thorne 1998 The methodology is explained in this document to provide a coherent set of qualitative and quantitative measures that can be used to define the river form and processes of a specific reach Repeat reconnaissance will allow conclusions to be drawn on the response of a reach to river restoration The river record sheets have been simplified to allow river managers to easily complete the sections These can then be reviewed by a geomorphologist hydromorphologist to determine the overall river response For review purposes it is strongly recommended that a detailed photographic record is taken to provide evidence for conclusions drawn The emphasis is placed on a careful and detailed visual assessment of the study reach Time should be taken to identify processes within the channel on the river banks and on the floodplain Measurements are also listed to enable channel response to be quantified where appropriate Tick boxes are provided where appropriate throughout the sheets to list reach characteristics In some cases it may be beneficial to provide a rank to each characteristic if several are present within the reach e g riparian vegetation type To do this it is recomm
6. d material size and fine gravel dominated low gradient shallower slope and wider valley floor often channel often dynamic channels better sequences of bars pools riffles rapids runs connected floodplains bars pools and riffles common lt J y Passive single thread meandering low gradient often resistant bed and banks e g clays less dynamic but sinuous planform often incised glides dominate Box 2 The River Influences are described through ticking the appropriate box This determines both catchment and local scale influences in terms of 1 Land Use whether the dominant surrounding land use is natural pasture arable urban or suburban 2 Sediment delivery whether the sediment inputs to the study reach from all sources is generally a strong moderate or low coarse or fine supply 3 Flow whether the general flow characteristics of the reach are high energy flashy often high gradient quick to respond to rainfall moderate energy flashy moderate energy subdued less responsive to rainfall longer time to peak low energy subdued often lower gradient less responsive to rainfall or low energy invariant flow is generally low energy and unchanging 4 Engineering tick appropriate box where any of these engineering schemes are present within the study reach hard banks e g concrete or brick hard bed e g concrete or brick weir dam groynes deflectors bridge crossing re sect
7. ended to use the Braun Blanquet Scale Number of individual examples present Recorded Rank and percentage cover of Reference Area Any number and more than 75 cover Any number and 50 to 75 cover Any number and 25 to 50 cover Any number and 5 to 25 cover Numerous but less than 5 cover or scattered with cover up to 5 A few individuals covering a small area A solitary individual covering a small area Note left and right bank is with reference to looking downstream along your watercourse THORNE C R 1998 Stream Reconnaissance Guidebook Geomorphological Investigation and Analysis of River Channels John Wiley amp Sons Chichester UK River Record Sheets User Guide Recommended field instruments to allow completion of the river record sheets are Pen pencil Clipboard Camera with GPS if available Tape measure at least 30m sticks Particle size sampler if available Cover Sheet Page 1 To be completed post audit This provides a summary of the audit once completed noting The issues being investigated The significant overall findings The major changes since the last survey General conclusions and recommendations The River e g Trent Date Flow level e g high moderate low and Recorder e g Mr Joe Bloggs are also included at the top of the page The page should also be signed and dated once complete and reviewed by a suitable person River Record Sheets User Guide ety
8. ioned River Record Sheets User Guide een y straightened dredges embanked distant i e set bank from banks or embanked adjacent i e on river banks 5 Riparian vegetation is the vegetation within the riparian corridor generally unimproved grassland improved grassland arable scrub deciduous forest coniferous forest mixed forest or other none 6 Riparian land use is the land use within the riparian corridor this is different to land use above which describes the wider catchment land use natural pasture arable urban or suburban There is also a sketch box available to note any significant features or influences River Character Page 3 Box 3 This begins to describe the River Characteristics locally within the reach in terms of sediment characteristics and morphological units which can then be related to the flow type characteristics on page 3 to define the hydromorphology of the reach Time should be taken in undertaking a thorough visual assessment and compiling a detailed photographic record for audit and review purposes Bed sediment is defined by it being boulder dominated boulder with cobbles cobbles cobbles with gravels gravels gravels with fine sediment this may be in the form of fine sediment infilling gravels and then fine sediment dominated In additions there may be a veneer of fine sediment across the top of gravels or a ripple dune feature associated to fine sediment dominated beds
9. measured include 1 2 10 11 12 13 14 19 16 1 18 19 20 21 Top vvidth right bank top to left bank top in metres Local width var channel with variation within the reach in metres Left bank height in metres Left bank angle approximation in degrees Right bank height in metres Right bank angle approximation in degrees Floodplain elevation above water level difference between water surface level and floodplain level in metres Average flow depth along the study reach in metres Depth variability e g at riffle and pools in metres Mean surface velocity throwing a stick in the water to estimate is suggested at different location in metres per second Maximum surface velocity quickest stick test in metres per second Bar width across the channel in metres Bar length along the channel in metres Berm width across the channel in metres Berm length along the channel in metres Bed sediment D50 size at which 50 per cent of the sample is less than Bed sediment D95 size at which 95 per cent of the sample is less than Bar sediment D50 size at which 50 per cent of the sample is less than Bar sediment D95 size at which 95 per cent of the sample is less than Berm sediment D50 size at which 50 per cent of the sample is less than Berm sediment D95 size at which 95 per cent of the sample is less than 16 River Record Sheets User Guide ere Diagra
10. ms of some of the physical measurements that can be taken are shown below There is also a sketch box available to produce an indicative sketch of the study reach to note any particular features or changes 17
11. nce of erosion of in channel deposits or islands 14 Bar dissection has bar erosion dissected a channel through the deposit 15 Chute development has bar or bank erosion developed into a chute channel that reconnects into the main channel 16 Overbank gravel splays look for evidence of overbank gravel deposition particularly after a flood event 17 Avulsion has the channel bed or bank changed completely following a significant flood event changing from one channel or feature type to another Box 5 The river bank types and processes are analysed in this section with a separation between left and right bank characteristics Again time should be taken in undertaking a thorough visual assessment and compiling a detailed photographic record for audit and review purposes Bank types 1 P 4 CE ge ae a ee N ee OE eh Ps Uniform alluvial Uniform gravel suppo 13 River Record Sheets User Guide ent Cantilever failure basal scour of non cohesive sands gravels which underlay a cohesive layer creates overhang which then fails at a critical state DS Beer a ma F gt VA SN NA ae Rotational slips slumping of the river bank Slipped blocks similar to rotational slips but over a concave face can be created by does not occur along a concave face more bank toe erosion and or steepening of a vertical slip There is also a sketch box available for detailing any notable characteristics
12. reated at times of higher flows varying across the mouth of the adjoining river channel sizes mixed sediment composition Cl River cliff steep bank often on the outside Berm a flat small in channel deposit often of a bend created by erosion of the bank toe lateral often fine sediment dominated in and bank collapse leaving a bare steep face lowland watercourses 10 River Record Sheets User Guide ting Z Floodplain features e g paleo channels Box 4 The river flow types and associated bed and bank activity and are recorded in this section The results of this should be closely linked to the morphological unit analysis on page 2 Again time should be taken in undertaking a thorough visual assessment and compiling a detailed photographic record for audit and review purposes Flow types example flow types are given below in the table below to help define the appropriate biotopes within the reach Flow types ME a SS a Cascade energetic flow type turbulent Chute energetic turbulent flow often over could include a small vertical drop boulder or bedrock 11 River Record Sheets User Guide TI fet y P3 fx gi ca tug te g Pow LA TL per IP ea Bogie DA mkaa rs ots Riffle often symmetrical ripples are created not waves shallow water depth less turbulent flow Glide deeper slow flowing little water Pool deep slow flowing no water
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