Black Gore Creek Total Maximum Daily Load

Sediment Source Monitoring 2006

Vail Pass, Colorado

Prepared for:

Eagle River Watershed Council

Prepared by:

RiverRestoration.org

The above photograph shows the full

subsurface basin monitored at cut slope

ditch 187.5.

The above photograph shows a culvert at mile marker 188.0. An

inventory of culverts was included in the 2006 monitoring efforts.

1

l. Introduction

This document presents data results that were collected to support the Black Gore Creek TMDL

monitoring. Specifically this document presents reduced data from monitored sediment sources

in the watershed. Sediment source monitoring results are used to recommend an annual export

load to move toward achieving stream health targets. Other simultaneous efforts are underway to

monitor in channel sediment sizes and biologic indicators of stream health. Data collection and

analyses herein represent the third annual sediment source monitoring effort.

II. Methods

Field data collection was conducted by RiverRestoration.org from September 14th through 29th,

2006. Jason Carey was the crew chief during the monitoring effort. An early winter snow storm

event accumulated snow and disrupted monitoring efforts for a few days. The following week

the weather warmed and a snow melt event occurred during data collection.

Eight sediment source categories were monitored, these include: Erosion Control Basins (ECB);

Gullies (G); Valley Floors (VF); Photo Monitoring (PM); Bridge Accumulation (BR); Center

Median (CM); Cut Slopes (CS); and Fill Slopes (FS). A detailed description of sediment source

monitoring procedures is in the BGC Sediment Source Monitoring Field Guide which can be

obtained from the Eagle River Watershed Council or RiverRestoration.org. In addition to annual

sediment source monitoring, a longitudinal profile and cross sections survey at MM 186.5, and

an inventory of culverts was conducted.

The mileage stationing used to identify reference points and locations was based on labeled

aerial photographs presented in the SCAP (2002); however, the SCAP mileage did not correlate

well with the Interstate 70 Mile Markers and the CDOT Bench Marks set along the roadway.

Some labeling, especially for some of the Cut Slopes, is based on the CDOT BM labeling.

Labels based on the CDOT BMs are identified where possible. The SCAP mileage stationing is

approximately 0.1 mile less than the CDOT BM stationing. In general mileage stationing used

herein may vary plus or minus 0.1 mile.

Photographic monitoring (PM) reference points were revisited at where they were set in 2004.

Photographic monitoring reference station Tag Line Post (TLP), at 188.3 was non existent. The

photograph was taken at an approximate location. The TLP at 184.5 had been removed from

traffic or plow activity, the PM was taken from an approximate location. A new TLP should be

established at PM 184.5, and 188.3 for future monitoring efforts. A new reference point near the

USGS gage station at 184.2 was set in 2006.

Erosion Control Basins, Gullies, Valley Floors and Center Medians were monitored with level

surveys of cross sections or profiles from established benchmarks. Disturbed TLPs observed in

2006 were re-established with elevations turned from the associated benchmark. Data collected

from the disturbed TLPs in 2006 were adjusted. Disturbed TLPs established elevations should be

updated in the field guide for 2007 field monitoring efforts.

2

Fill slope rill density was measured at the top of the slope. Vegetative cover percentages on the

FS were based on visual observation and are somewhat subjective. Slope angles were estimated

in 2004 with an inclinometer.

Cut Slopes (CS) monitoring was performed at all CS to verify if sediment controls, such as

sediment basins installed by CDOT, appeared adequate. Distances for a CS was a measure

between a culvert (or direct stream input) and the nearest upstream sediment control. Distances

were based on reference stationing at established sediment control basins. Cut Slopes upslope of

Black Lakes were not monitored because all sediments originating from CS upslope of Black

Lakes are currently being retained by Black Lakes.

Bridge accumulation and Valley Floors were monitored by single depth measurements. Single

depth measurements were monitored with a sediment probe and distance tape.

III. Results

Photographic Monitoring

In general most PM photographs showed more dense vegetation growth. Most PM on fill slopes

show evidence of uncontrolled stormwater by an increase in density and size of rills and

sediments deposits smothering vegetation. Supplemental photographs of erosion control basins

showed that most are over flowing with sediments and had not been maintained in 2006 (see

Table 6 Cut Slopes Results). Table 1 summarizes the evident changes in the PM data between

2004 and 2006. Erosion or sedimentation was visually evident in most of the photographs.

Vegetation density was also observed in the photographs.

Table 1 Photographic Monitoring Log

2004 2005 2006

Reference

Point Photo

Description 9/13-9/17 9/14-9/15

9/14-

9/29 Comparison

PM

Confluence

Towards US

BGC and

confluence with

Gore Creek

IMGP026

6.JPG

2005-09-20

013.JPG

2006/pic

s/IMGP

0683.JP

G

More dense vegetation on

deposits at downstream end

of island.

WTP #2

LEP

Towards WTP #2

REP

IMGP025

3.JPG

2005-09-20

011.JPG

2006/pic

s/IMGP

0684.JP

G

More dense vegetation

growth between 2004-2006.

Newly paved road in 2006.

WTP #1

LEP

Towards WTP #1

REP

IMGP025

2.JPG

2005-09-20

012.JPG

2006\pic

s\IMGP

0685.JP

G

2004 photo shows channel

braiding. Dense vegetation

growth between 2004-2005.

CDOT BM

181.9

Towards East and

center median I-

70

IMGP026

7.JPG

2005-09-20

031.JPG

2006\20

06-09-

26\IMG

P2039.J

More dense vegetation

growth in center median.

There are some invasive

weeds.

3

PG

ECB 182.2

REP

Towards ECB

182.2 LEP

IMGP025

4.JPG

2005-09-20

014.JPG

2006\20

06-09-

26\IMG

P2043.J

PG

Photographs show there is a

deposition trend (x-sec

surveys show trend also).

Vegetation is establishing on

deposits. Braiding channels

are forming as sediments

transport through ECB.

ECB 182.8

#2 LEP

Towards ECB

182.8 #2 REP

IMGP025

7.JPG

2005-09-20

035.JPG

2006\20

06-10-

03\IMG

P2124.J

PG

Photograph shows sediments

deposition between 2004 and

2005. No noticeable change

occurred between 2005 and

2006. Cross-sections show

deposition trend.

ECB 182.8

#1 LEP

Towards ECB

182.8 #1 REP

IMGP025

5.JPG

2005-09-20

036.JPG

2006\20

06-10-

03\IMG

P2125.J

PG

Vegetation appears

smothered from deposition

between 2004 and 2005. No

noticeable change between

2005 and 2006.

PM 182.9

Towards

westbound I-70

fill slope

IMGP027

9.JPG

2005-09-20

034.JPG

..//2006/

2006-

10-

03/IMG

P2079.J

PG

No change. Fillslope has

good vegetation cover and no

slumping or uncontrolled

stormwater is evident.

PM 183.5

Towards DS

BGC, 180’ US

mm183.5

IMGP027

8.JPG

2005-09-20

033.JPG

2006\20

06-10-

03\IMG

P2075.J

PG

Photographs show slight

widening from left bank

failure (2004-2005 front left

of photographs). There are

sand deposits on right toe,

photo 2077.

BR 184.4

From near BR

184.4 towards E.

abutment S. wing

wall east bound I-

70

IMGP027

7.JPG

2005-09-20

015.JPG

2006\20

06-09-

26\IMG

P1986.J

PG

Deeper deposits, rilling and

transport of sediments is

evident.

PM 184.2

Stand

approximately

20’ D/S from

gage station.

From Center of

channel look

2006\20

06-10-

03\IMG

P2073.J

PG Established 2006

4

upstream towards

gage station pipe.

PM 184.5

Towards east

bound I-70 fill

slope

IMGP025

8.JPG

2005-09-20

017.JPG

2006\20

06-09-

26\IMG

P1987.J

PG

Disturbed PM, bent B&C in

2006. Shoulder was recently

paved during 2006

monitoring. Rills have

grown larger and deeper at

top of fill slope. Some rills

are linked together and

forming concentrated

drainage down fillslope.

BR 184.9

Towards east

abutment east

bound I-70

IMGP027

6.JPG

2005-09-20

061.JPG

2006\20

06-09-

26\IMG

P1994.J

PG

2006 Photograph appears to

be taken from slightly

different angle. There may

be increased buried

vegetation. Field notes

commented that there are

buried silt fences under

abutment. Deep deposits

were noted in Polk Creek

from sidecast (Photo1995).

However, there are no

deposits at monitoring post.

BR 185.2

Towards south

pier east bound I-

70

IMGP027

5.JPG

2005-09-20

030.JPG

2006\20

06-09-

26\IMG

P1999.J

PG

Photo 2000 shows line of

sidecast buildup and 2001

example of gully transporting

sidecast material down from

ECBs under 185.2 Bridge.

Photograph from 2006

appears to be zoomed in and

taken from north side of post,

not behind post; resulting to

inconclusive PM comparison.

PM 186.0

Towards East

looking at cut

slope ditch

IMGP027

4.JPG

2005-09-20

010.JPG

2006\20

06-10-

03\IMG

P2072.J

PG

Recently paved shoulder.

Field notes document

freeze/thaw weathering and

slope mass failure (large

chunks of debris).

PM 186.2

Towards

eastbound I-70

fill slope

IMGP026

8.JPG

2005-09-20

062.JPG

2006\20

06-09-

26\IMG

P2010.J

PG

Uncontrolled stormwater,

rilling at top of fill slope.

Field notes indicated

increased native bank erosion

5

G 186.8 #3

LEP

Towards G 186.8

#1 REP

IMGP026

0.JPG

2005-09-20

04.JPG

..\..\..\M

y

Pictures\

2006-

10-

16\IMG

P2218.J

PG

Photographs 2004-2006 show

gully erosion (x-section

shows degradation) with

delta forming at toe.

Increased bank erosion along

this reach (background of

photos).

PM 186.9

From CDOT BM

186.9 towards

West and fill

slope

IMGP026

9.JPG

2005-09-20

07.JPG

2006\20

06-09-

26\IMG

P2011.J

PG

No change occurred. Slight

rilling at top of fill slope.

VF 187.1

Towards US flow

line and deposit

IMGP025

9.JPG

2005-09-20

08.JPG

2006\pic

s\IMGP

2017.JP

G

More vegetation growth.

Shoulder from 187.2 runs

through culvert and is source

to VF 187.1 Photograph

2017 is looking up from post

towards small deposit fan.

G 187.1 #3

LEP

Towards G 187.1

#2 REP

IMGP028

1.JPG

2005-09-20

057.JPG

2006\20

06-09-

26\IMG

P2021.J

PG

No change apparent from PM

comparison.

PM 187.3

Towards

downstream BGC

and natural right

bank erosion

IMGP027

0.JPG

2005-09-20

060.JPG

2006\20

06-09-

26\IMG

P2052.J

PG

Photographs show no change

of slope. Photographs

between 2004-2006 shows

there may be deposition in

the stream.

PM 187.5

Towards East

looking at cut

slope ditch

IMGP027

3.JPG

2005-09-20

09.JPG

2006\20

06-10-

03\IMG

P2070.J

PG

2006\20

06-10-

03\IMG

P2069.J

PG

Paved shoulder and two

subsurface ECB were

installed in 2006.

Photograph 2071 shows

subsurface basin full.

Sediments transport through

culvert to VF 187.5. (See

Capital Project Valley Floor

Stabilization 187.5 “Other

End of the Pipe” report).

VF 187.5

#2 REP

Towards VF

187.5 #2 LEP

IMGP026

1.JPG

2005-09-20

019.JPG

2006\20

06-09-

26\IMG

P2038.J

PG

Crib walls were built to

stabilize delta deposits in

2006.

6

VF 187.5

#1 REP

Towards VF

187.5 #1 LEP

IMGP026

2.JPG

2005-09-20

018.JPG 2039

Cross logs were installed in

2006 to dissipate energy and

trap sediments.

PM 187.6

Towards

eastbound US-6

grade and

significant slope

erosion

IMGP026

3.JPG

2005-09-20

020.JPG

2006\20

06-10-

03\IMG

P2065.J

PG

2006\20

06-10-

03\IMG

P2164.J

PG

Vegetation growth (more

dense grasses and pine

sapling growth).

G 187.75

LEP

Towards DS flow

line gully and

bike path

IMGP026

5.JPG

2005-09-20

021.JPG

2006\20

06-10-

03\IMG

P2060.J

PG

Right bank gully erosion

(notice exposed roots).

Photograph 2167, 2168 is

looking up gully; note that

previous erosion control

measures are buried

(landscape fabric, coir logs).

PM 187.9

Towards

upstream Black

Gore Creek

IMGP026

4.JPG

2005-09-20

022.JPG

2006\20

06-10-

03\IMG

P2057.J

PG

Snow covered during 2006

monitoring. The beaver dam

blew out during runoff and

stored sediments have

transported downstream.

PM 188.3

From edge of

pavement bike

path towards flow

line gully and

BGC

IMGP027

2.JPG

2005-09-20

023.JPG

2005-09-20

024.JPG

2006\20

06-10-

03\IMG

P2066.J

PG

No TLP and snow covered

during 2006 monitoring.

Photographs 2004-2005 show

gully widening. Photograph

2182, shows gully down to

BGC. Photograph 2183

shows culvert under

bikepath.

PM 188.9

From CDOT BM

188.9 towards

West and median

IMGP027

1.JPG

2005-09-20

028.JPG

2006\20

06-10-

03\IMG

P2068.J

PG

More rill growth and

denuded vegetation on south

side of median.

7

Cross Section Monitoring

Monitoring observations are presented in Table 2 for surveyed cross sections. In general,

Erosion Control Basins that capture significant runoff have experienced sedimentation. Most

cross sections of Fill Slope Gullies show erosion. Figures 1-14 show cross sections.

Table 2 2005 and 2006 Cross Section Comparison

Cross Section

Average

Degradation

(ft2)

Notes

WTP #2 NA Beaver dam washed out

WTP #1 NA

ECB 182.2 NA Cross section shows braiding

channels and deposition.

ECB 182.8

#2 NA

This is an in-channel Erosion

Control Basin. Cross section shows

scour on left and right channels and

deposition on mid-channel island

(deposits formed from abandoned

beaver dam).

ECB 182.8

#1 NA

Cross section shows sediments

transporting through in-channel

basin.

G 186.8 #3 1.64

Cross section shows erosion.

Photographs 1990 look downstream

at center line of gully.

G 186.8 #2 0.84 Cross section shows the erosion

around and under the pipe.

G 186.8 #1 0.9 Cross sections show erosion in

center of channel.

G 187.1 #3 0

No significant change. Cross section

show there may be hill slope

slumping at top of gully.

G 187.1 #2 5.16 Channel degradation. Corrugated

metal pipe is disconnecting.

G 187.1 #1 21.7 Channel degradation.

G 187.75 22.25 Photograph 2224 shows bank failure

VF 187.5 #2 15 Channel degradation.

VF 187.5 #1 8.03 Channel degradation.

Total

Average

degradation

9.4 Average degradation at monitored

fill slope gully cross sections.

8

X-sec figures

Figure 1 WTP #1

WTP #2

88.00

90.00

92.00

94.00

96.00

98.00

0 20 40 60 80 100 120 140 160

2004

2005

2006

Figure 2 WTP #2

WTP #1

85.00

87.00

89.00

91.00

93.00

95.00

97.00

99.00

0 20 40 60 80 100 120 140 160

2004

2005

2006

9

Figure 3 ECB 182.2

ECB 182.2

93.00

93.50

94.00

94.50

95.00

95.50

96.00

96.50

0 20 40 60 80 100

2004

2005

2006

Figure 4 ECB 182.8 #1

ECB 182.8 #1

86.00

86.50

87.00

87.50

88.00

88.50

89.00

89.50

90.00

90.50

91.00

0 20 40 60 80 100 120 140

2004

2005

2006

10

Figure 5 ECB 182.8#2

ECB 182.8 #2

86.00

86.50

87.00

87.50

88.00

88.50

89.00

89.50

90.00

90.50

91.00

0 20 40 60 80 100 120 140 160 180 200

2004

2005

2006

Figure 6 Gulley 186.8 #1

G 186.8 #1

51.50

52.50

53.50

54.50

55.50

56.50

57.50

0 10 20 30 40

2004

2005

2006

11

Figure 7 Gulley 186.8 #2

G 186.8 #2

87.00

88.00

89.00

90.00

91.00

92.00

93.00

94.00

95.00

96.00

0 10 20 30 40

2004

2005

2006

Figure 8 Gulley 186.8 #3

G 186.8 #3

134.50

135.00

135.50

136.00

136.50

137.00

137.50

138.00

138.50

139.00

139.50

0 10 20 30

2004

2005

2006

12

Figure 9 Gulley 187.1 #1

G 187.1 #1

19.00

21.00

23.00

25.00

27.00

29.00

31.00

0 20 40 60 80 100 120

2004

2005

2006

Figure 10 Gulley 187.1#2

G 187.1 #2

47.00

48.00

49.00

50.00

51.00

52.00

53.00

54.00

55.00

56.00

0 5 10 15 20 25 30 35

2004

2005

2006

13

Figure 11 Gulley 187.1 #3

G 187.1 #3

91.00

91.50

92.00

92.50

93.00

93.50

94.00

0 5 10 15 20 25 30

2004

2005

2006

Figure 12 Valley Floor 187.5 #1

Vally Floor 187.5

Gully Cross Section 1

80.00

80.50

81.00

81.50

82.00

82.50

83.00

83.50

84.00

84.50

85.00

85.50

0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0

Station

Elevation 2004

2005

2006

14

Figure 13 Valley Floor 187.5#2

Valley Floor 187.5

Gully Cross Section 2

89.00

90.00

91.00

92.00

93.00

94.00

95.00

96.00

15 20 25 30 35 40 45 50

Station

Elevation 2004

2005

2006

Figure 14 Gulley 187.75

G 187.75

51.00

52.00

53.00

54.00

55.00

56.00

57.00

58.00

59.00

60.00

61.00

0 5 10 15 20 25 30

2004

2005

2006

15

Single Depth Monitoring

Monitoring points that required a single depth measurement, Valley floors (VF) and Bridge

Accumulation (BR), are presented in Table 3. Deposits at the monitoring posts indicate transport

of materials off of the Valley Floors and from Bridges. Of the single depth measurements two

thirds of the bridges showed deposits and 1/3 of the Valley Floors showed deposits.

Table 3 Single Measurement Monitoring

Reference

Point

Concurrent

Deposits at

Reference

2004

Depth

of

Deposits

(feet)

2005

Deposits/TLP

(feet)

2006

Deposits/TLP

(feet)

Change in Deposits

(feet)/ Notes

VF 184.5

No 0 0/4.2 0/4.2 No sediments at

TLP, however

deposits are noted

1.5’ upgradient of

the post. Three delta

deposits are

accumulating at toe

of FS upgradient of

this VF.

VF 186.9 No 0 0 0/3.94 No

VF 187.1 Yes 4.0+ 4.0+ 4.0+/1.51 No

BR 184.4

No 3 0.8/3.4 0.75/3.35 Not at TLP.

However significant

sidecast

accumulation with

rills is under bridge.

Depth probes of

sidecast material 3’

deep.

BR 184.9 Yes 1.5 3.32/2.9 3.3/2.9 No

BR 185.2 Yes 1.5 1.5 3.47 Yes

16

Center Medians

Four Center Median (CM) profiles are presented in Table 4. In 2004 these monitored sites had

evidence of sediments transporting into the culverts that drain the medians. These sites were

randomly chosen to represent all center median areas. In 2006 all CM showed deposits at invert

as well as deposits 10’ and 30’ feet upstream.

Table 4 Center Median Monitoring

Center

Median

Concurrent

Deposits at

Invert

2004

Deposit

Depth

10’/30’

Upstream

(feet)

2005 Deposit

Depth 10’/30’

Upstream

(feet)

2006 Deposit

Depth 10’/30'

Upstream

(feet) Notes

CM

181.9 Yes 2.0/1.0 1.15/1.0 1.6/1.05

Deposits at invert, change

in deposition indicates that

sediments are transporting

through system. Rilling

around drainage tile that

feeds to culvert. Coir logs

in place u/s invert 15’, 35’,

50’ are ½ buried with

sediments. Well vegetated

80%; mostly aster and

wheatgrass with some

weeds.

CM

184.5 Yes 0.5/0.5 0.5/0.3 0.52/0.25 Sand deposits at invert.

CM

186.9 Yes 1.0/0.5 0.5/0.5 0.7/0.5

0.5 deposits on top of

concrete with vegetation

growth.

CM

188.8 Yes 0.5/0.5 0.5/1.0 0.6/0.5 Sand deposits at invert.

17

Fill Slope Monitoring

Table 5 presents observations made at fill slopes (FS). Slope grades were measured in 2004 with

an inclinometer. Sediment laden snow sidecast is most likely the significant source of sediments

on the fill slopes. Large pieces of asphalt found near the toe of most fill slopes was taken as

evidence of snow transporting materials down slopes, in addition to fluvial transport of materials.

Sheet flow down the fill slopes would likely not transport the large pieces of asphalt. Most

jersey barriers are effective at controlling sheetflow. However, there are some jersey barriers

that have eroded at the toe and are no longer effective.

Table 5 Fill Slope Monitoring

Fill

Slope

Slope

Grade

%

2004 Rills

per 25 feet/

Vegetation

Cover %

2005 Rills

per 25 feet/

Vegetative

Cover %

2006 Rills per

25 feet/

Vegetation

Cover % Change from Previous Year

F1-

182.8 57 6/70 0/75 0/70 None

F0-

183.2 50- 0/100 0/100 0/90 Increase in buried vegetation

F0-

183.7 50- 0/100 0/100 0/90 Increase in buried vegetation

F0-

184.0 50- 0/100 0/90 0/90 None

F1-

184.2 65 0/70 0/70 0/70 None

F0-

184.5 57 7/70 5/70 3/65

Recently graded at top of fill

slope. However there are three

large rills (forming channels)

transporting significant deposits

to the toe of the slope.

Photograph 1979 shows one of

the channels formed from

concentrated sheet flow down the

rills. Vegetation cover is

dominated by thistle and cheat

grass. Fill slope extends from

184.5-184.6.

F0-

184.7 50 4/90 4/90 5/70

Recently graded. Vegetation on

slope is dominant thistle and

cheat grass.

F1-

185.9 57 4/80 5/80 15/60

Increase in rill development and

buried vegetation. Photograph

2007 shows the slope mass failure

at top of slope which may form a

18

gulley in the near future.

F1-

186.2 79 6/90 4/70 6/75 Well defined deep rills.

F1-

186.3 65 6/90 8/60 5/70 None

F0-

186.4 71 2/60 8/70 7/65 None

F1-

186.5 65 6/90 8/70 10/80

Increase in rills. Decrease in

buried vegetation.

F1-

186.8 71 9/70 9/70 12/70

Freshly graded shoulder however,

rill development beyond graded

shoulder and edge of pavement

down the fill slope. Large rills

forming two gullies at top of

slope; photograph 2220 shows

one of the gullies, photograph

2221 shows the recently graded

slope.

F0-

186.9 57 5/80 5/80 9/65

Fill slope 186.98-187.0 rill

developing under jersey barrier;

photograph 2222.

F0-

187.1 50 0/90 0/90 2/70

Increase in rills and buried

vegetation.

F0-

187.5 50 3/100 2/90 7/65

Above fill slope adjacent to I-70,

jersey barrier has significant side

cast with rill development and

two gullies behind it; however

large bike path swale at toe of

slope goes to ECB 187.37 with

adequate sediment storage

capacity.

F1-

187.7 71

Gully

Formation/

20

Gully

Formation/

30

Gully

Formation/30

Uncontrolled Cut Slope Monitoring

Table 6 presents Cut Slope (CS) findings. These observations recognize where sediments from

cut slopes have adequate BMP basins, no controls in place or overflowing basins. Most erosion

control basins were full in 2006 and overflowing. Data presented below includes bike path

swales.

19

Table 6 Uncontrolled Cut Slope Monitoring

Cut

Slope

Culvert Distance

to U/S

control

(feet)

Sedimentation Change from Previous

Year and Field notes

CS

182.16

WB

182.16 1373 (#26

ECB)

Significant Basin is overflowing with

sediment. West bound cut

slope connected without

BMP to 182.42

CS-182.3

EB

None, flows into BMP #28 182.3 0 (#28B

ECB

182.3)

Moderate BMP #28 A&B 2041,

2042. Uncontrolled

shoulder downstream of

182.2 routes sidecast to

culvert 181.0

CS-182.4

EB

None, flow though ECB#29

under S. Bridge Abutment

528

(culvert

182.5)

Moderate-

Significant

ECB#29 near full,

Sedimentation most likely

from sidecast; photograph

2096.

CS 182.5

EB

182.5/182.75 2323 (#30

ECB

182.94)

Moderate-

Significant

Culvert drains d/s ECB

182.94 #30. Uncontrolled

until culvert at 182.5.

There is one culvert located

at 182.75.

183.3/183.65

183.49/183.6 (2005)

CS-183.3

EB

183.7, natural drainage at

183.9/183.5.

5280

None

Moderate Not adequate ECB at

183.37. Cut slope extends

from 184.3 to 183.3.

Controlled cut slope from

183.3 down to ECB #30

182.94.

20

CS-184.8

WB

184.75 212 (#33

ECB

184.79)

Moderate ECB #33 184.79. There are

two ECBs #21A, #21B at

184.62 downstream that are

good.

CS-185.1

WB

185.1 528, none Moderate Cut slope extends to 185.2.

DS ECB #20 185.02 is

adequate but stormwater is

not routed to it.

CS 185.1

EB

Significant Significant sedimentation

in swale, ECB #33 184.99

overflowing and too small,

photographs 1991, 1992.

Erosion control logs and

silt fences are not

maintained under south

abutment, deposits over

3.3’ deep; photograph

1993.

CS 185.5

EB

Moderate ECB #35 185.75 too small,

photograph 2002. Paved

shoulder and ripraped

bikepath swale. ECB #34

at 185.5 is good but doesn’t

control shoulder or swale.

ECB #19 185.28 under

bridge has adequate

sediment storage capacity,

however a gulley is

forming at the outlet.

CS 185.4

WB

185.4 528, none Uncontrolled Cut slope

extends to 185.5

CS-185.7

WB

185.75 1478

(#15

185.91)

Significant ECB #15 185.91 is full;

photograph 2114.

Downstream ECB’s #16A,

#16B and at 185.65, #17 at

185.33 and #18 at 185.3

are in good conditions.

21

CS-

186.0EB

186 2535 (#37

185.98-

185.5#34)

Significant Bike path swale and

shoulder controlled from

186.0-186.8. ECB #36

186.1 too small but feeds

into good storage ECB #38

186.0, photograph 2008.

Very large ECB #37 at

185.98 has good storage,

however swales not routed

to it. Downstream ECB at

185.90 is overflowing

2002, 2005, uncontrolled

cut slope and bike path

swale extends from 185.98

down to culvert at 185.5

2004.

CS-186.0

WB

186.0/186.25/186.45/186.7/186.8 4752

(ECB

#14,

186.9)

Significant Adequate storage at ECB

#14 at 186.90. Subsurface

basin 186.85 is full (photo

2111). Subsurface basin

186.28 is full (photograph

2112). Paved between

186.9 and 186.3.

Uncontrolled cut slope

extends from ECB 186.9 to

186.0 culvert.

CS 187.3

EB

1056 Significant Bikepath swale controlled

by ECB 187.37 #41, and

#42A. ECB 187.2 too

small, uncontrolled

shoulder extends 187.4-

187.2

CS-187.1

WB

187.07 1426 (# 9

ECB

187.34)

Moderate-

Significant

Adequate ECB storage at

187.34. Downstream at

ECB #11 187.07 is full;

photograph 2107.

Approximately 150’

downstream ECB (# not

identified) controls native

gully and shoulder.

CS-187.4

WB

187.39/187.5/187.75 2587

(ECB

187.88)

Excessive ECB #8 187.88 over

flowing. Subsurface basins

187.5 are full; photographs

2090, 2091. No control

from culvert 188.0 down to

culvert 187.39.

22

BS 188 Uncontrolled bike path

swale Black Lakes down to

culvert 187.9.

Moderate

(2004)

Increased sedimentation

Significant

(2005)

BMP #7 188.33 over

flowing with sediments

(photo 2086). No control

from 188.73 down to

culvert 188.0. Culvert 188

has significant deposits

(0.6’) at invert photo 2087.

CS-188.0

WB

188 1742

(ECB #7

188.33)

Excessive

(2006)

CS 188.5

WB

188.6/188.5 1214

(BMP #6

188.73)

US Black

Lakes

Small drainage culvert at

188.6 has two flow

directions which flow into

188.7 and 188.5. No

control from BMP 188.73

down to 188.5.

188.73 CS-188.7

WB

188.8 (Drainage)

1531

(BMP

188.73,

BMP

189.09)

US Black

Lakes

Moderate

New US BMP basins at

188.72 #6A and 188.73

#6B have adequate storage.

Erosion control log placed

at 188.9. Culvert 188.8 is

paved DS to 188.73. BMP

at 189.09. Uncontrolled cut

slope is between 189.09 to

drainage 188.8. Moderate

deposits (0.5’) at invert of

culvert 188.8. Photos

2081,82,83

*Stationing based on CDOT MM

23

Cu

lver

t In

ven

tory

Table 7 provides the approxim

ate location, condition, and photograph of culverts inventoried. These culverts were below Black Lakes

no. 2. Not all culverts on west Vail pass were inventoried.

Tab

le 7

2006 C

ulv

ert

Inven

tory

D

raft

Mile

Marker

Diameter

(inches)

Condition

Sedim

ents

at Invert

Erosion Notes

Photograph

181.9

24 Good

no

no

Drains EB and W

B, CM?. Corrugated m

etal pipe

with grate.

2040

182.92

24 Good

no

no

Drains EB storm

water. Upstream

ECB 182.94

#30 adequate.

183.3

60 Good

yes

no

Drains EB storm

water and natural gully.

Upstream

ECB full. Corrugated m

etal pipe.

2097, 2098,

2099

184.3

30 Good

no

no

Drains EB storm

water, reverse flow and natural

gully at 184.1. Corrugated m

etal pipe.

184.4

30 Good

no

no

Drains EB storm

water, reverse flow and natural

gully at invert. Corrugated m

etal pipe with grate.

185.37

24 Good

no

no

Drains EB and bike path storm

water.

186

18 Moderate

no

no

Drains EB storm

water into ECB 186.0. Failing

(hole) at invert of culvert. Corrugated m

etal pipe.

186.1

36 Moderate

no

no

Drains WB storm

water. Outlet at toe of fill slope.

2130

186.33

30 Poor

yes

yes

Drains WB storm

water. Corrugated m

etal culvert

disconnected at outlet. Gully starting to occur

with delta deposit in BGC.

2134, 2135

24

186.5

12 Good

no

no

Drains to toe of fill slope

186.51

30 Poor

yes

yes

Drains WB storm

water. Corrugated m

etal pipe

blown out. Gully form

ing with LWD.

2104, 2105,

2138

186.8

24 Good

no

no

Drains to toe of fill slope

2141

186.9

24 Poor

yes

yes

Drains WB storm

water. Corrugated m

etal pipe is

blowout. Significant gully erosion. Monitoring

site.

2103

186.92

18 Poor

yes

yes

Drains EB and bike path storm

water. Corrugated

metal pipe disconnected. Gully form

ing down fill

slope.

2102, 2142

187

30 Moderate

no

no

Drains natural WB gully. Erosion control logs

placed upstream

of culvert are buried with

sedim

ents. No deposits at invert.

2093

187.07

24 Moderate

yes

no

Drains WB storm

water. Upstream

ECB 187.07 is

full. Erosion control logs placed around invert are

buried.

2106, 2148

187.1

24 Poor

yes

yes

Drains bike path swale. Disconnected at

downstream

end. Significant gully erosion.

Monitoring site.

2149

187.2

24 Good

yes

no

Drains EB storm

water. Upstream

ECB 187.2 is

full, deposits at invert 3.5''. Drains to bike path

swale controlled by ECB 187.4 #41. Plastic pipe.

2053, 2152

187.2

18 Moderate

yes

no

Drains EB storm

water to bike path swale

controlled by ECB 187.4 #41. Corrugated m

etal

pipe 1/3 full of deposits at outlet.

2151

187.4

12 Moderate

no

yes

Storm

water flows into gabion to prevent gully

degradation. Flow has routed around gabion

causing further gully degradation. Corrugated

metal pipe ~5' w

est of larger pipe.

2153, 2154

25

187.4

30 Moderate

no

yes

Storm

water flows into gabion to prevent gully

degradation. Flow has routed around gabion

causing further gully degradation. Corrugated

metal pipe.

2153, 2154,

2155

187.5

24 Poor

yes

no

Abandoned corrugated m

etal culvert. Near upper

bench cribwall VF stabilization capital project,

2006. Culvert clogged with sedim

ents.

2156

187.5

36 Poor

yes

yes

Corrugated m

etal pipe with gully form

ing at

outlet. M

onitoring site and capital project VF

stabilization, 2006.

2159

187.75

24 Poor

yes

yes

Corrugated m

etal pipe blown out with significant

gully erosion. Failed gabions and fabric wraps in

gully channel. Drains to ECB 187.7 #43 bike path

swale control, full 2006. Monitoring site.

2167, 2168

187.82

12 Good

no

no

Drains I-70 under bike path to well vegetated

slope (w

illows), slight gully form

ing.

2170

187.85

30 Moderate

yes

no

Drains EB storm

water. Flow runs under culvert

and drains to bike path swale and ECB #43,

overflowing 2006. Swale is full and flow runs

over path transporting sedim

ents down natural

slope. Natural slope gullying process is occurring

from concentrated storm

water runoff.

2058, 2059

187.9

24 Poor

yes

yes

Drains I-70 under bike path to BGC. Corrugated

metal culvert is blown out with gully form

ation

and headcut into the bike path.

2056, 2171

187.92

Good

no

no

Drains I-70 under bike path to BGC.

187.97

24 Poor

yes

yes

Drains under bike path to BGC. Corrugated m

etal

culvert. Gully form

ing and starting to headcut

into culvert.

2172

26

188

24 Poor

yes

no

Culvert is clogged, flow runs under culvert and

drains to uncontrolled bike path swale.

2054, 2055,

2175

188

24 moderate

yes

no

Drains WB storm

water. Upstream

ECB 188.33

adequate. Deposits at invert are 0.5' deep.

Corrugated m

etal pipe set subgrade with grate.

2086

188.1

Good

no

yes

Drains EB storm

water to rocked gully that drains

to bike path swale.

188.1

24 Poor

yes

yes

Drains under bike path to BGC. Invert looks

good, outlet is buried. Gully form

ing between

bike path and BGC.

2176, 2177

188.2

24 Poor

yes

yes

Drains under bike path to BGC. Invert buried,

outlet form

ing gully.

2180, 2181

188.3

24 Poor

yes

yes

Drains at top of bike path to rocked gully. Invert

1/3 full of deposits.

2182, 2183,

2184

188.4

24 Moderate

no

yes

Drains I-70 under bike path to m

idway down fill

slope. Gully starting to form

.

2185

188.5

18 Poor

yes

no

Corrugated m

etal pipe is clogged with sedim

ents.

Located just downstream

spillway.

2186

188.8

48 Good

yes

no

Drains WB uncontrolled cut slope. Shoulder is

not paved. Deposits at invert are 0.5' deep.

2081,2082,

2083

* Rapid inventory, data collected 09/27/06-09/29/06

* M

ile Marker determined in field using aerial photographs and existing CDOT m

arkers (+/- 0.1 m

ile)

* Inventory does not include all culverts on W

est Vail Pass

* East Bound (EB), W

est Bound (WB), Erosion Control Basin (ECB), Black Gore Creek (BGC), Large Woody Debris (LWD), Center

Median (CM)

27

Longitudinal profile and Cross sections at MM 186.5.

Beavers constructed a dam in the channel at 186.5. Monitoring of cross sections and a

longitudinal profile was continued in 2006 to show the aggradation rate of the channel behind

the beaver dam. Figures 15-18 show the surveyed cross sections and longitudinal profile of the

reach.

Figure 15 Cross Section #1 186.5

BGC 186.5 x sec#1

-3.5

-3

-2.5

-2

-1.5

-1

-0.5

0

0 5 10 15 20

station (ft)

elevation (ft)

2004 USFS

2006 RR.org

Figure 16 Cross Section #2 186.5

BGC 186.5 x sec#2

-3.5

-3

-2.5

-2

-1.5

-1

-0.5

0

0.5

0 5 10 15 20 25

station (ft)

elevation (ft)

2004 USFS

2006 RR.org

28

Figure 17 Cross Section #3 186.5

BGC 186.5 x sec #3

-3

-2.5

-2

-1.5

-1

-0.5

0

0.5

1

0 5 10 15 20 25 30 35

station (ft)

elevation (ft)

2004 USFS

2006 RR.org

Figure 18 Longitudinal Profile of reach at 186.5

BGC Longitudinal Profile 186.5

-6

-5

-4

-3

-2

-1

0

1

2

0 25 50 75 100 125 150 175 200 225 250 275

Distance (ft)

Elevation (ft)

2006 RR.org

Monitoring and Load Allocation

A quantitative sediment yield was calculated for the various contributing erosional processes.

Table 8 shows the sediment yield results. The information presented herein represents a baseline

for future monitoring efforts to be compared to, allowing for quantitative analysis. Over time the

multiple sediment contributing processes and variables can be better calibrated. With continued

monitoring efforts a better estimate of the sediments inputs and controls can be calculated; and

the balance between the sediment load and biological and physical stream health can be better

determined. Appendix C provides the spread sheet model used to calculate the sediment budget.

29

Table 8 2006 Sediment Budget Result

2005 2006

SOURCE CATEGORY ZONES LA

(Tons/Year) LA

(Tons/Year)

Applied Traction Sand 1 10600 30000

Sand Stockpile Erosion 1 0 0

Slope Mass Wasting 2 10 10

Natural Background 3 30 30

Black Lakes 3 0 0

Channel Bed Active Storage 3 2600 2300

Fill Slope Gullies 1,2 2100 2200

Fill Slopes 1,2 1700 1600

Valley Floors 2 1200 975

Cut Slopes 1 2000 2300

Accumulation Under Bridges 2 500 500

Exacerbated erosion of native slopes 2 250 250

Bike path swales 1,2 200 300

Center Medians 1 200 200

Exacerbated Bank Erosion 3 20 20

Other 0 0

Sediment Sources TOTAL LA 21410 40685

BGC Loading Capacity (LC) 8600 8600

Exported Sediment Load 1,2,3 6621 6500

Recommended Exported Load 1,2,3 6400 25585

* The recommended exported load should always be equal to, or greater than 6400 tons/year * Recommended exported load of 6400 is the difference of the average annual sand applied (15,000 tons) and average annual load capacity (8,600 tons) * Load allocations are estimates based from source monitoring data, and best professional judgement. See Appendix E for detail.

* Imported and exported load estimates per CDOT September, 2006

Recommendations for Future Monitoring

Higher resolution mapping is expected to be complete summer 2006 (CDOT, 2005). These maps

should be brought into the field and utilized to mark detail such as: approximate delineation of

drainage areas, effective routing paths and runoff process, all bmp locations and type, areas of

exacerbated native erosion, beaver dam activities, ect.

Additional photographic monitoring should be established near the 186.1 and 186.2 area. From

2004 to 2005 significant change occurred near these areas due to a breached beaver dam at 186.1

and significant deposition at 186.2. Photographs have been taken of these areas, however no TLP

has been set. Photographic monitoring at 184.2 near the USGS gage station has been

established.

30

Subsurface sediment monitoring is recommended to better evaluate and understand channel bed

storage and transport. These subsurface core samples should be collected bi-annually during

September at surface sediment sample locations. These samples should be analyzed

volumetrically to determine sediment size distributions.

Future monitoring may include 185.0 snowstorage site with potential to transport sediment down

native gully, photograph 1996.

Longitudinal and cross sections surveys, as well as pebble counts should continue MM 186.5.