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A Sediment Study of LittleLeading Creek
Guy Riefler1, Ben Stuart1, Tiao Chang1,Barbara Flowers2, Jennifer Chapman-Kleski3, Yanhui Fang1
1Department of Civil Engineering2Ohio Dept of Natural Resources3Environmental Studies
2Ohio University
Little Leading Creek
Appalachian Plateau Region ofSoutheast Ohio
5th Order Perennial Tributary toLeading Creek a Tributary of theOhio River
Watershed Size 25.6 Mi2Main Stem Length 9.1 Miles
3Ohio University
Impairment of Creek
• fails to meet warm water habitatcriteria because of excessivesand
• filled pools results in poorbreeding and few hiding places
• fish assemblages diverse but ofvery small size
• history of frequent flooding
4Ohio University
Sand
• deeplyentrenchedchannels
• highlyerodiblebanks
• poor habitatin channel forfish
5Ohio University
And More Sand
• deep sanddeposits inchannel
• during lowflow, surfacewater drainsthrough thesanddeposits
6Ohio University
Mining History
• majority of the active surface miningtook place between 1950 and 1964
• reclaimed AML = 1.1 Mi2
• unreclaimed AML = 1.2 Mi2
• 9% of watershed
• over $4 million spent on AMLreclamation in Little Leading Creekwatershed from 1979-1990
7Ohio University
Mining Erosion
• potential erosion ratefrom strip mining =200+ ton/acre (USDA,1985)
• translates in LittleLeading CreekWatershed to annualerosion of possibly423,000+ tons for 15-40 years
8Ohio University
Study Objectives
• Characterize Sediment Within Stream Bed• Measure Sediment Load and Transport Rate• Identify Sediment Sources• Propose Restoration Alternatives
9Ohio University
Estimating Sediment Transport
Continuous StageReadings
Velocity Measurementsto Estimate Discharge
Bed Load andSuspended
Load Measurements
10Ohio University
Peterson Study SegmentVelocity Measurements
Velocity Measurements recordedusing an Electromagnetic Flow Meter
Velocity Profile Plot of Cross Section
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
0 5 10 15 20 25 30
Distance (Ft)
Dis
tance fro
m W
ate
r S
urf
ace (
Feet)
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
0 5 10 15 20 25 30
Velo
city (
ft/s
)
Distance from Water Surface Velocity
Average Velocity .89 ft/s
Total Discharge 11.09 CFS
Water Surface ?
11Ohio University
Discharge Rating Curve
• stage dischargemeasurements overrange of inbank flows
• two distinct curves• transition at 29.1 cfs
represents shift fromsection control tochannel control
• sediment onlytransported out ofsection during higherflow events
12Ohio University
Bedload Transport Observations
• after high flow events, poolsand riffles evident
– floods scour sand out ofchannel
• during low flows, bedloadtransport still high as sand isredistributed
– between storm events poolsfill with sand
13Ohio University
Suspended Sediment Collection
Non-wadable Flows• US DH-59
Wadable Flows• Depth Integrated
• Hand Held Sampler ModelNumber USDH-48
16Ohio University
Sieved Bedload
% FinerThan Particle Size
D16 0.36
D50 0.50
D84 1.80
poorly graded coarse sand
0
10
20
30
40
50
60
70
80
90
100
0.01 0.10 1.00 10.00 100.00
Particle Size (mm)
Cum
ula
tive (
% F
iner
Than)
0
20
40
60
80
100
120
140
160
180
We
igh
t P
as
sin
g S
iev
e (
g)
Cumulative % Less Than Weight
17Ohio University
Bedload Transport Rates
• higher bedloadobserved thansuspended sediment
• at higher flowssuspended sedimentmay exceed bedload
• estimated sectiontransport– SS = 10 ton/yr– BL = 18 ton/yr
• estimated channeltransport– SS = 7 ton/yr– BL = 8 ton/yr
Suspended Sediment Rating Curve
Bedload Rating Curve
y =
8.46x0.86
R2 = 0.95
y =
44.35x0.54
R2 = 0.74
1
10
100
1,000
10,000
1 10 100 1000
Discharge (cfs)
Lo
ad
(lb
/d)
18Ohio University
Assessment of AML Reclamation
• headwater and tributarycreeks had well gradedsediments including graveland large stones
• often pavement apparent
• sites vegetated and noobvious erosion problems
• where is all this sand comingfrom?
19Ohio University
Evaluating Bank Erosion
Method: Repeat Survey
Multiple Cross-sections
and
Longitudinal Profiles
20Ohio University
Study Segments
Main Stem Study SegmentsRail Road Bridge .05Rutland Bridge 1.9 River MiPeterson Bridge 3.1 River MiSoil and Water 4.6 River MiPriddy Bridge 7.0 River MiAdkins 8.2 River Mi
Tributary Study SegmentsCremean 3.6 River MiSide Road 6.65 River MiHarrisonville 9.3 River Mi
21Ohio University
Subtle Channel Changes
576
577
578
579
580
581
582
583
584
585
586
0 10 20 30 40 50
Distance (ft.)
Ele
va
tio
n (
ft.)
Summer 05'
Fall 05'
Summer 06'
548
550
552
554
556
558
560
562
564
0 10 20 30 40 50
Distance (ft.)
Ele
va
tio
n (
ft.)
Summer 05'
Fall 05'
Summer 06'
574.5
575
575.5
576
576.5
577
577.5
0 100 200 300 400 500 600
Aug-05 Jul-06 Linear (Jul-06) Linear (Aug-05)
22Ohio University
Peterson Cross-section
576
577
578
579
580
581
582
583
584
585
586
-20 0 20 40 60
Aug-05 Jul-06 Oct-06
DimensionChange %
Yr 1 Yr 2 Cumulative
Area (Ft2) 3.2 0.8 4.0
Width (Ft) 4.2 1.0 5.3
Dmean (Ft) 0.0 0.0 0.0
Dmax (Ft) 1.4 4.1 5.5
23Ohio University
Bank Erosion Common on Mainstem
• deeply entrenchedchannel
• poorly vegetatedand easily erodablebanks
• in many locationscattle have accessto creek
• bank erosion likelyprimary sedimentsource
24Ohio University
Sediment Origin
• borings to revealdepths of sedimentin floodplain
• presence of largeamounts of coal andorange stainingmay be goodindicators for miningrelated erosion
25Ohio University
Soil Borings
• sets of soil boringswere drilled at twocreek cross-sections
• continuous splitspoon sampling 4-14’
• cores collected inplastic sleeves forextraction andanalysis in lab
26Ohio University
Soil Boring Locations
• Harrisonville– site of initial flooding problems– wide flat pasture– significant entrenchment and
erosion• Peterson
– wooded– more narrow valley section– relatively stable banks– rock pavement observed after
scour events
27Ohio University
Typical Cores
• mostly poorlygraded sandwith betweenclay layers
• coal chips andfines spreadthrough soil
• some layerswith lots of coal
• significantorange stainingoften adjacentto heavy coallayer
28Ohio University
Deeper Cores
• at 6-10 feet mostsoils turned fromtan or brown togrey or black
• occasionally atdepth severalinches ofcarbonized,recentlydeposited leaves,sticks, logs, andgrass present
29Ohio University
Coal?
• coal chips difficult to distinguish from other blackdeposits (particularly when wet)
• need to closely inspect each fragment• coal fines need to be identified with a microscope
slag coal bark basalt
30Ohio University
Harrisonville Stratigraphy
• sand andclay foundup to 14 ftdeep andover 200 ftfromchannel
• old riverbeds foundover 100feet fromchannel
31Ohio University
Coal in Harrisonville Cores
• coal chipsand finesfoundthroughout
• valleyinundatedwithsedimentfrom thestrip miningover 14feet deep
32Ohio University
Peterson Stratigraphy
• sand andclay found upto 10 ft deepand over 100ft fromchannel
• old riverbeds andthick layersof recentlydepositedorganicmatter found
clay found up
and over 100
33Ohio University
Coal in Peterson Cores
• coal foundas deep as12 feet
• no coalfound in orbelowwetlandsediments
• possiblyoriginalfloodplainbeforeinundatedwith sand
34Ohio University
Likely History of Little Leading Creek
• during and after strip mining very large sediment loadsinundated the watershed forming valley plugs
• during this period Little Leading Creek resembled a braidedstream that filled the hollows and valleys with sand and clay
• after AML reclamation, the sediment source was removed andthe channel began to cut downward through the easily erodablematerial
• the result is deeply entrenched banks with persistant sedimentsource to the creek from the valley and floodplain deposits
• low gradient areas act as sediment traps, locking sediments inthe system except during high flow
35Ohio University
Conclusions
• large quantities of sand transported within the systemprimarily as bedload
• uniform sand the dominant deposit
• sand trapped in channel, only leaves the system duringhigh flow events
• major source of sediment currently from bank erosion
• floodplain deposits highly erodable and a direct result ofstrip mining
36
Restoration Recommendations
• limit primary sediment source to thecreek
• stabilize 2.75 miles of the mostdegradable stream banks
– reconnect channel to floodplain
– raparian revegitation
– proper channel design
• coexist with cattle
– exclusion from channel
– drill wells to provide alternatewater source
– established crossings
1. Bank StabilizationFailing Banks River Mile Total
Howard/Clark Property 9.1 through 9.4 0.3
Jewell Property 7.8 through 8.4 0.6
Johnson/Priddy Property 6.9 through 7.0 0.1
Wm Sterns Property 6.3 through 6.9 0.6
Fort Meigs 5.3 through 5.5 0.2
Soil and Water Property 4.8 through 4.95 0.15
Soil and Water Property 4.55 through 4.65 0.1
Colman Property 4.1 through 4.4 0.3
Barrett Property 3.6 through 3.7 0.1
Peterson Property 3.1 through 3.2 0.1
Casto Property 2.5through 2.6 0.1
Rutland BaseBall Fields 1.65 through 1.75 0.1
Total 2.75
37
Restoration Recommendations
• remove existing sediment fromchannel
• during bankfull or greater flow collecttransported sand in a pair of ponds
• will require periodic sand removal
• install downstream of sediment trap
• generate enough velocity to maintainpools
• log vanes, vortex weirs, ...
2. Sediment Trap
primary settlingpond
secondarysettling pond
hard ramp tolimit entry flow
3. Habitat ImprovementStructures