WSP02347

• File Number: 8102
• Description: Arkansas River Basin Basic Hydrology
• State: CO
• Basin: Arkansas
• Water Division: 2
• Date: 5/7/1999
• Author: Inter-Fluve Inc
• Title: Fluvial Geomorphic Assessment of Upper Arkansas River - Final Report
• Water Supply Pro - Doc Type: Report/Study

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O~1788

Table of Contents (continued)

List of Tables

Table 4.1 Project subreaches.............................................................................................23
Table 4.2 Profile and planform characteristics of project subreaches ............................. 24
Table 4.3 Cross-section characteristics of project subreaches.......................................... 27

Table 6,1 Measured channel sinuosity: 1939, 1957, and 1996........................................ 38
Table 6.2 Historic split flow conditions: 1939,1957, and 1996......................................38
Table 6.3 Measured low flow topwidth, 1939, 1957, 1996.............................................. 40
Table 6.4 Relationships between bankfull discharge, effective flow (4% duration), and

channel morphology. ... .... .... ..... ...,......... ...... ...... ... .......... ..... ...... .... ... ..................... ..., 44

Table 7.1 Summary of reach study sites..........................................................................48
Table 7.2 Annual peak discharges used in incipient motion analyses............................. 53
Table 7.3 1M Site average bankfull discharges and associated recurrence intervals....... 54
Table 7.4 1M Site flow distribution for modeled recurrence intervals ............................ 55
Table 7.5 Manning's n-value calculated using the slope area procedure. ....................... 56
Table 7.6 Reach average hydraulic characteristics ...........................................................61
. Table 7,7 Shield's parameter calibration ......................................................................... 67
Table 7.8 Shield's parameter comparisons ......................................................................67
Table 7,9 Site averaged incipient motion characterization.............................................. 68

Table 8,1 Entrainment potential, project subreaches ....................................................... 79

Table 9.1 Example compound channel geometry, Subreach 2........................................ 97
Table 9.2 Example compound channel geometry, Subreaches 3-7 .............:................... 98

List of Plates

Plate I Coarse sediment contribution from left bank terrace, Subreach 2...................... 25
Plate 2 Fine tailings deposit on left bank bar surface, Subreach 2 .................................. 25
Plate 3 Piling revetment just upstream of Lake Fork confluence, Subreach 2 ................ 26
Plate 4 Mouth of Lake Fork Creek, and main stem Arkansas River ...............................26
Plate 5 Local split flow/channel braiding, Subreach 3 .................................................... 28
Plate 6 Sediment distribution on bar surface, Subreach 3 ................................................28
Plate 7 Active bank undercutting/channel widening, Subreach 3..................................... 29
Plate 8 Active bank erosion /channel widening, Subreach 4 ........................................... 29
Plate 9 Perched woody debris on small island, Subreach 4.............................................. 31
Plate 10 Sediment accumulation at split flow confluence, Subreach 4............................31
Plate II Coarse bar substrate overlain by phytotoxic tailings deposits, Subreach 5....... 32
Plate 12 Relatively stable channel planform, Subreach 7................................................. 32

May 7, 1999

Fluvial Geomorphological Assessment
Upper Arkansas River

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