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From page 119... ... D-1 Part 1 Field Data Sheets, D-2 Part 2 South Platte River Site Reconnaissance and Preliminary Data Sheets, D-11 Part 3 South Platte River Case Study: Final Data Sheets and Application of the Guidelines, D-28 Part 4 Debris Scour Calculations, D-47 A P P E N D I X D Field Data Sheets and Case Study Read the entire page →
From page 120... ... Field Data Sheets 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Upstream Reach Length: feet / miles 17 18 19 20 Yes ____ No ____ Yes ____ No ____ 21 22 Yes ____ No ____ Unknown ____ Evidence of Regular Flooding: Yes ____ No ____ 23 Yes ____ No ____ 24 25 26 27 28 29 30 Historic Ground Photos avaialable for: 31 32 Historic Aerial Photos available for: Stream Flow Data or Records available for: 33 34 Scour Calculations available for: Hydraulic Models available for: 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 Descriptions: Description: Average Upstream Channel Width at Crossings and/or Straight Reaches: feet (top bank to top bank) Width (ft) Read the entire page →
From page 121... ... D-3 52 53 54 55 56 Sand ___ Gravel ___ Cobble ___ Bldrs ___ 57 58 59 60 61 Bars: 62 63 64 65 General Bank Face Shape: Convex _____ Concave _____ Vertical _____ Undercut/Overhanging _____ 66 LB Toe Sediment Accumulation (Basal Endpoint Control) : Significant _____ Moderate _____ Negligible _____ 67 RB Toe Sediment Accumulation (Basal Endpoint Control) Read the entire page →
From page 122... ... 101 102 103 104 105 106 107 108 109 Pier # Abutment 1 2 3 4 5 6 7 8 9 Abutment 110 P&P Shape / / / / / / / / / / / 111 Width / / / / / / / / / / / 112 Hgt/Depth / / / / / / / / / / / 113 Length / / / / / / / / / / / 114 115 Span/Gap Abut - 1 1-2 2-3 3-4 4-5 5-6 6-7 7-8 8-9 9-10 # - Abut 116 P&P Shape / / / / / / / / / / / 117 Width / / / / / / / / / / / 118 Hgt/Depth / / / / / / / / / / / 119 Length / / / / / / / / / / / 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 Type of Debris Accumulation on Bridge(s) : Existing Debris Accumulations ( P lanform & P rofile Descriptions) Read the entire page →
From page 123... ... 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 Photo # 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 (f) Cross Section Sketch of Upstream Bridge Face (looking downstream - include important features and dimensions) Read the entire page →
From page 124... ... D-6 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 Item B1b records the general upstream channel and flood plain characteristics. Item B1a records the general characteristics of the watershed upstream of the bridge site. Read the entire page →
From page 125... ... D-7 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 Item C1f Cross Section Sketch of Upstream Bridge Face is drawn here. The sketch should be viewed in the downstream direction and should include important features and dimensions. Read the entire page →
From page 126... ... D-8 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 Item C1g Field Site Photo Log is used to record photos taken at the site. The descriptions of the photo and any important features in the photo are recorded here as well. Read the entire page →
From page 127... ... D-9 Sheltered by upstream forest? SHELTERED Location Category DETERMINE LOCATION CATEGORY In channel between tops of banks? Read the entire page →
From page 128... ... D-10 Horizontal / vertical gap / span wider than design log length? LOW Gap/Span Blockage Potential GAP / SPAN IN SHELTERED LOCATION CATEGORY Potential for gap / span blockage due to large adjacent pier accumulations? Read the entire page →
From page 129... ... D-11 D.1 Introduction The intent of the ﬁeld reconnaissance was to investigate potential case study locations on the South Platter River in Colorado. The Field Data Sheets were used to document site characteristics such as channel type and size, channel instability, bank erosion and retreat, and bank vegetation characteristics in detail. Read the entire page →
From page 130... ... Bridge RD-50 has three sharp-nosed piers skewed approximately 5° to high flows and about 18 in. wide; two piers had debris buildup on the nose and sides (Figure D.7) Read the entire page →
From page 131... ... D-13 Figure D.2. Map showing area of Northern Colorado investigated for potential case study sites. Read the entire page →
From page 132... ... D-14 Figure D.5. Historic and recorded flow rates for Bridge RD-37. Read the entire page →
From page 133... ... D-15 Figure D.7. Looking upstream left bank to right bank at Bridge RD-50. Read the entire page →
From page 134... ... D-16 Figure D.9. Pier 1 with debris and scour hole. Read the entire page →
From page 135... ... Figure D.11. Looking down on Pier 2 and debris. Read the entire page →
From page 136... ... D-18 Figure D.13. Aerial view of Bridge RD-50 and the upstream corridor. Read the entire page →
From page 137... ... D-19 Figure D.14. Looking upstream from Bridge RD-50. Read the entire page →
From page 138... ... D-20 ATTACHMENT 2 Field Data Sheets Bridge WEL 50/67a for assessing woody debris delivery and accumulation potential at a bridge site Read the entire page →
From page 143... ... D-25 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 The general characteristics of the upstream channl and flood plain can be acquired or measured from maps, aerial photos, and survey data. Prior to recording this information, the user should determine the appropriate reach length to be evaluated. Read the entire page →
From page 144... ... D-26 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 Vertical Channel Stability identifies whether aggradation or degradation is occurring in the upstream channel since both can contribute to debris recruitment. Degradation results in bank erosion and bank retreat, whereas aggradation can induce overbank f Item C1d records general information on the riparian corridor upstream of the bridge site. Read the entire page →
From page 145... ... D-27 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 Item C1h Cross Section Sketch of Upstream Bridge Face is drawn here. The sketch should be viewed in the downstream direction and should include important features and dimensions. Read the entire page →
From page 146... ... D-28 Estimated potential for debris production: HIGH Estimated potential for debris transport and delivery: HIGH Estimated debris accumulation potential: Left Bank Abutment -- LOW Pier 1 -- MEDIUM Pier 2 -- HIGH Pier 3 -- HIGH Right Bank Abutment -- LOW Estimated span blockage potential: Span 1 -- LOW Span 2 -- LOW Span 3 -- LOW Span 4 -- LOW P A R T 3 South Platte River Case Study: Final Data Sheets and Application of the Guidelines Summary of Assessment of Debris Production, Transport, Delivery, and Accumulation Potential Bridge WEL 50/67A over South Platte River near Hardin, Weld County, Colorado Read the entire page →
From page 147... ... D-29 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Upstream Reach Length: 17 18 19 20 Yes __X_ No ____ Yes __X_ No ____ 21 22 Yes _____ No __X__ Unknown _____ Evidence of Regular Flooding: Yes ____ No _X__ 23 Yes _X__ No ____ 24 25 26 27 28 29 30 Historic Ground Photos avaialable for: 31 32 Historic Aerial Photos available for: Stream Flow Data or Records available for: 33 34 Scour Calculations available for: Hydraulic Models available for: 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 Descriptions: Vertical abutment cap wall with rock riprap spill-through abutment slopes. Nose: sharpWidth (ft) Read the entire page →
From page 148... ... D-30 52 53 54 55 56 57 58 59 60 61 62 Bars: 62 63 General Bank Face Shape: 64 LB Toe Sediment Accumulation (Basal Endpoint Control) : 65 RB Toe Sediment Accumulation (Basal Endpoint Control) Read the entire page →
From page 149... ... D-31 99 100 101 102 103 104 105 106 107 Pier # Abutment 1 2 3 4 5 6 7 8 9 Abutment 108 P&P Shape / T / NA 1* / / / / / / / / / 109 Width / / / / / / / / / / / 110 Hgt/Depth / 2' / 3' / / / / / / / / / 111 Length / / / / / / / / / / / 112 113 Span/Gap Abut - 1 1-2 2-3 3-4 4-5 5-6 6-7 7-8 8-9 9-10 # - Abut 114 P&P Shape / / / / / / / / / / R / IC 115 Width / / / / / / / / / / 8' / 10' 116 Hgt/Depth / / / / / / / / / / 7' / 8' 117 Length / / / / / / / / / / 25' / 30' 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 Typical Key Log Length (range - ft) Read the entire page →
From page 150... ... D-32 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 Photo # 184 P1/12 185 P1/13 186 P1/14 187 P1/15,16 188 P1/17 189 P1/18 190 P1/19 191 P1/20 192 193 194 195 196 197 198 199 200 (g) Field Site Photo Log View looking down on Pier #1 debris accumulation at nose of pier View TL to TR showing debris on wall piers and upstream face of bridge View looking upstream, note debris in channel and on eroding banks View looking down on log with root wad and other debris on center pier (Pier #2) Read the entire page →
From page 151... ... D-33 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 55 56 57 58 59 60 61 62 62 63 64 65 66 67 68 69 70 71 72 73 54 Existing Debris Accumulations records the location of debris relative to the bridge site. Records whether or not bars are present at the site and the type of bar since bars can influence debris grounding and accumulation. Read the entire page →
From page 152... ... D-34 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 Item C1f Cross Section Sketch of Upstream Bridge Face is drawn here. The sketch should be viewed in the downstream direction and should include important features and dimensions. Read the entire page →
From page 153... ... D-35 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 Item C1g Field Site Photo Log is used to record photos taken at the site. The descriptions of the photo and any important features in the photo are recorded here as well. Read the entire page →
From page 154... ... D-36 Seasonal High Flow Level Design Flood Flow Level Sheltered Top Bank/ Flood Plain Top Bank/ Flood Plain Channel Debris Path (approx.) Meander Bend Seasonal High Flow Level Design Flood Flow Level Sheltered Top Bank/Flood Plain Top Bank/ Flood PlainChannel DebrisPath (approx.) Read the entire page →
From page 155... ... D-37 Sheltered by upstream forest? SHELTERED Location Category DETERMINE LOCATION CATEGORY In channel between tops of banks? Read the entire page →
From page 156... ... D-38 Sheltered by upstream forest? SHELTERED Location Category DETERMINE LOCATION CATEGORY In channel between tops of banks? Read the entire page →
From page 157... ... D-39 Horizontal / vertical gap / span wider than design log length? LOW Gap/Span Blockage Potential GAP / SPAN IN SHELTERED LOCATION CATEGORY Potential for gap / span blockage due to large adjacent pier accumulations? Read the entire page →
From page 158... ... D-40 Horizontal / vertical gap / span wider than design log length? LOW Gap/Span Blockage Potential GAP / SPAN IN SHELTERED LOCATION CATEGORY Potential for gap / span blockage due to large adjacent pier accumulations? Read the entire page →
From page 159... ... D-41 LOW Accumulation Potential LOCATION CATEGORY LOCATION CATEGORY MEDIUM Accumulation Potential HIGH Accumulation Potential HIGH, CHRONIC Accumulation Potential YES NO PIER OR SUBSTRUCTURE DESIGN SOLID WITH APERTURES Potential for Delivery of Debris Low High Low High Low High DEBRIS PATH DEBRIS PATHCHANNEL FLOOD PLAIN /TOP BANK CHANNEL FLOOD PLAIN /TOP BANK Potential for Delivery of Debris Potential for Delivery of Debris PIER OR SUBSTRUCTURE SECTION IN SHELTERED LOCATION CATEGORY LB ABUTMENT ACCUMULATION POTENTIAL LOW Accumulation Potential LOCATION CATEGORY LOCATION CATEGORY MEDIUM Accumulation Potential HIGH Accumulation Potential HIGH, CHRONIC Accumulation Potential YES NO PIER OR SUBSTRUCTURE DESIGN SOLID WITH APERTURES Potential for Delivery of Debris Low High Low High Low High DEBRIS PATH DEBRIS PATHCHANNEL FLOOD PLAIN /TOP BANK CHANNEL FLOOD PLAIN /TOP BANK Potential for Delivery of Debris Potential for Delivery of Debris PIER OR SUBSTRUCTURE SECTION IN SHELTERED LOCATION CATEGORY PIER 1 ACCUMULATION POTENTIAL Flowchart D Read the entire page →
From page 160... ... D-42 LOW Accumulation Potential LOCATION CATEGORY LOCATION CATEGORY MEDIUM Accumulation Potential HIGH Accumulation Potential HIGH, CHRONIC Accumulation Potential YES NO PIER OR SUBSTRUCTURE DESIGN SOLID WITH APERTURES Potential for Delivery of Debris Low High Low High Low High DEBRIS PATH DEBRIS PATHCHANNEL FLOOD PLAIN /TOP BANK CHANNEL FLOOD PLAIN /TOP BANK Potential for Delivery of Debris Potential for Delivery of Debris PIER OR SUBSTRUCTURE SECTION IN SHELTERED LOCATION CATEGORY PIER 2 ACCUMULATION POTENTIAL LOW Accumulation Potential LOCATION CATEGORY LOCATION CATEGORY MEDIUM Accumulation Potential HIGH Accumulation Potential HIGH, CHRONIC Accumulation Potential YES NO PIER OR SUBSTRUCTURE DESIGN SOLID WITH APERTURES Potential for Delivery of Debris Low High Low High Low High DEBRIS PATH DEBRIS PATHCHANNEL FLOOD PLAIN /TOP BANK CHANNEL FLOOD PLAIN /TOP BANK Potential for Delivery of Debris Potential for Delivery of Debris PIER OR SUBSTRUCTURE SECTION IN SHELTERED LOCATION CATEGORY PIER 3 ACCUMULATION POTENTIAL Flowchart D Read the entire page →
From page 161... ... D-43 LOW Accumulation Potential LOCATION CATEGORY LOCATION CATEGORY MEDIUM Accumulation Potential HIGH Accumulation Potential HIGH, CHRONIC Accumulation Potential YES NO PIER OR SUBSTRUCTURE DESIGN SOLID WITH APERTURES Potential for Delivery of Debris Low High Low High Low High DEBRIS PATH DEBRIS PATHCHANNEL FLOOD PLAIN /TOP BANK CHANNEL FLOOD PLAIN /TOP BANK Potential for Delivery of Debris Potential for Delivery of Debris PIER OR SUBSTRUCTURE SECTION IN SHELTERED LOCATION CATEGORY RB ABUTMENT ACCUMULATION POTENTIAL Flowchart D 0 50 100 150 200 250 300 350 400 450 DISTANCE FROM LEFT ABUTMENT (ft) Read the entire page →
From page 165... ... D-47 Steps 1 through 5 The case study of the South Platte River results indicate that there is a high potential for debris production, high potential for debris transport and delivery, and a high potential for accumulation of debris at Pier 2, which is located in the center of the bridge near the middle of the channel. The span length is 112.9 ft (34.4 m) Read the entire page →
From page 166... ... The projected width of the pier without debris is: Step 7 Determine the effective pier width with debris for the maximum debris dimensions. Maximum debris dimensions are W = 30 ft (9.1 m) Read the entire page →

From page 119...

... D-1 Part 1 Field Data Sheets, D-2 Part 2 South Platte River Site Reconnaissance and Preliminary Data Sheets, D-11 Part 3 South Platte River Case Study: Final Data Sheets and Application of the Guidelines, D-28 Part 4 Debris Scour Calculations, D-47 A P P E N D I X D Field Data Sheets and Case Study