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HALEY & ALDRICH, INC. 6 Waterfront Plaza 500 Ala Moana Boulevard, Suite 6-250 Honolulu, HI 96813 808.587.7747
www.haleyaldrich.com
30 September 2022
File No. 0203303
County of Hawai’i Department of Public Works
101 Pauahi Street, Suite 7
Hilo, Hawai’i 96720
Attention: Stephen M. Pause, P.E.
Director, Department of Public Works
SUBJECT: Rockfall and Slope Instability Mitigation and Conceptual Design Summary Report
Valley Road Evaluation Project
Honokaa , Hawai‘i
Haley & Aldrich, Inc. (Haley & Aldrich) is pleased to submit this report providing mitigation
recommendations for rockfall and slope instability hazards along Waipi‘o Valley Road. Valley
‘o. The Road is narrow and
winds along the steep hillside of the south valley wall, with an approximately 800 feet elevation change
in 0.7 mile. The location of the project area is shown on Figure 1 and the overall alignment on Figure 2.
Our work was completed in general accordance with our scope and fee estimate provided on 11 March
2022, and our subconsultant agreement with County of Hawai‘i Department of Public Works (DPW)
dated 20 April 2022.
1 Project Understanding
gic slope hazards and related roadway stability issues. As part of
a Preliminary Geotechnical Engineering Evaluation, Hart Crowser, Inc. (now a part of Haley & Aldrich)
geologists conducted an initial investigation, rating the slope hazards within the scope of the Federal
Highway Administration (FHWA) Rockfall Hazard Rating System (RHRS) and assessing for risk using a
numerical approach developed by the Australian Geomechanics Society. The results from this study
were provided in a report, dated January 2022 (the “Initial Evaluation”), that highlighted the need for
remediation and provided preliminary recommendations for rockfall mitigation.
Haley & Aldrich has conducted further site reconnaissance to evaluate in more detail the conditions
identified during the initial evaluation and to define the type of mitigation recommended for segments
of the roadway. The findings of this evaluation are to be used by the team to develop strategies and
methods to avoid and minimize geologic hazards and to design rockfall mitigation measures. This report
provides a summary of the findings of our additional field evaluation and estimated order-of-magnitude
costs for recommended mitigations.
Valley Road Evaluation Project
30 September 2022
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2 Scope of Work
Our scope of work for this additional field assessment included conducting a drone LIDAR survey of the
work area and conducting site reconnaissance to evaluate potential changes in conditions at the three
sections (upper, central, and lower) identified during the Initial Evaluation. Our work also further
identifies the nature and scope of mitigation recommended along the roadway corridor; identifies
priority areas, such as areas where vegetation and slopes could be cut back, that could be addressed
quickly to reduce risk; and recommends priorities for scheduling/phasing the mitigation. Our findings
are detailed in this report.
3 Field Evaluation
We conducted the additional field evaluation of the project alignment from May 16 through 20, 2022.
The purpose of the evaluation was to further evaluate features and areas of geologic concern identified
in our Initial Evaluation as well as to note changes in conditions and additional features of geologic
concern. The roadway sections delineated in the Initial Evaluation were also assessed for geologic
feature and mitigation considerations and were updated to generate revised section limits along the
roadway. See Table 1 below.
Limitations of the field work included constraints on visibility from vegetative obstructions and, due to
the shear steepness of the site, limited access on both the upslope and downslope sides.
In our Initial Evaluation report, the term “Section” referred to the Upper, Central, and Lower lengths of
the roadway that were grouped together based on similar conditions. In this report, these groupings are
referred to as the Upper, Central, and Lower Areas. The term “Section” is used to discuss subsections of
the Upper, Central, and Lower Areas. The Sections discussed in this report are based on the 11 transects
defined for use in the “Rockfall Hazard Rating System,” or RHRS assessment of the Initial Evaluation. The
Stationing referenced herein is strictly a project stationing created for our geologic hazard analysis and
does not correspond to formal County roadway stationing.
Table 1. Revised Section Coverages with Stationing
Section Area Start Station End Station Approx. Length (ft)
1 Upper 0+00 2+15 215
2 Upper 2+15 7+35 520
3 Central 7+35 11+50 415
4 Central 11+50 20+85 935
5 Lower 20+85 24+85 400
6 Lower 24+85 27+70 285
7 Lower 27+70 29+95 225
8 Lower 29+95 31+25 130
9 Lower 31+25 33+45 220
10 Lower 33+45 36+35 290
11 Lower 36+35 39+50 315
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4 Findings
As discussed in our Initial Evaluation, along the Upper Area of the roadway, steep, exposed residual soil
slopes are susceptible to instability, as indicated by past failures. Along the Central and Lower Areas of
the roadway, rockfall hazards are present on the upslope side of the road and quantitative hazard
ratings from RHRS scoring and RocFall modeling indicates mitigation for the hazard is warranted. We
also discussed that there are several mitigation options that can help stabilize the road (upslope and
downslope) and reduce the risk to vehicle and pedestrian travel from potential rockfall and slope
instability. Our findings from our additional field evaluation are discussed below.
UPSLOPE HAZARDS FEATURES
Our Initial Evaluation of geologic hazards on the upslope side of the roadway found rockfall and failing
masses of soil and vegetation to be the predominant geologic hazards to the roadway. To further
evaluate the upslope geologic hazards along the roadway, nine unique geologic hazard feature types
were observed and recorded by physical and relative location. The physical location of each feature was
captured using a GPS device and mapped in Figures 3 through 13. The relative location for each feature
is defined by the section containing the feature. We note that the accuracy of the GPS point and line
features was limited due to poor satellite connectivity related to topographic and vegetative
obstructions along the roadway. Thus, GPS feature locations shown on Figures 3 through 13 are
approximate and not intended for survey or construction use.
The nine upslope geologic hazard types are listed and defined in Table 2 below. Table 2 also includes the
shorthand symbol assigned to the feature type used to label the features, as shown in Figures 3 through
13 as well as a reference to an example photo, which has been included in our Photo Log (Appendix A).
A full list of the collected GPS points is included in Appendix B.
Table 2. Upslope Geologic Hazard Feature Types
Feature Type Feature Type
Symbol
Definition Example Photo
(Feature ID)
Corestone CS Variably sized, spherical blocks of differentially
weathered basalt via spheroidal weathering, within
weathered bedrock, or saprolite.
Photo 1
(CS-01)
Differential
Erosion
DE Increased rates of erosion due to lithologic occurrence
of fractures, voids, pores, or similar properties, and
leading to overhanging or undercutting conditions on
the slope.
Photo 2
(DE-02)
Overhang OH An overhanging feature such as a root mat or undercut
block of rock.
Photo 3
(OH-01)
Rock Package RP A discernable group of rocks that has similar
composition, weathering patterns or joints, with dilated
jointing and translation along joints. These groups of
rocks generally pose a greater risk of failure than the
surrounding rocks of an outcrops.
Photo 4
(RP-36)
Root Wedging RW Exacerbation of joints by the infiltration of growing
roots.
Photo 5
(RW-01)
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Table 2. Upslope Geologic Hazard Feature Types
Feature Type Feature Type
Symbol
Definition Example Photo
(Feature ID)
Scallop SC A mass of soil and rock that remains on the slope face
after erosion of surrounding material.
Photo 6
(SC-02)
Tree Tree Trees growing on the crest of, or in the face of, the
roadcut or outcrop.
Photo 7
(Tree-02)
Upslope Gully UG An observable topographic relief and debris chute
caused by surface runoff, possibly exacerbated by
constructed water control features such as swales.
Photo 8
(UG-05)
Upslope Rock
Source
RS An upslope outcrop of rock that can be visibly seen
from the road and has the potential of shedding rock
down slope.
Photo 9
(RS-04)
DOWNSLOPE HAZARD FEATURES
Our evaluation of geologic hazards on the downslope side of the roadway found gullies to be the
predominant hazard to the corridor. These gullies display both head and side wall scarps and are
vegetated with young growth. Surface water runoff was not observed during the investigation; however,
given the proximity of the gullies to swales constructed along the roadway, it is likely that the diverting
of surface water is adding to gully formation. To further evaluate the downslope landslide hazards along
the roadway, unique geologic hazard feature types were observed and recorded by physical and relative
location. The physical location of each feature was captured using a GPS device and mapped in Figures 3
through 13. The relative location for each feature is defined by the section containing the feature. The
scope of our evaluation for the downslope hazard features was limited to what was visible from the
roadway and does not consider a remediation for these hazards.
The downslope geologic hazard is listed and defined in Table 3 below. Table 3 also includes the
shorthand symbol assigned to the feature type used to label the features, as shown in Figures 3 through
13, as well as a reference to an example photo, which has been included in our Photo Log (Appendix A).
A full list of the collected GPS points is included in Appendix B.
Table 3. Downslope Geologic Hazard Feature Types
Feature Type Feature Type
Symbol
Definition Example Photo
(Feature ID)
Downslope
Gully
DG An observable topographic relief and debris chute
caused by surface runoff, possibly exacerbated by
constructed water control features such as swales.
Photo 10
(DG-10)
GEOLOGIC HAZARDS SUMMARY
To summarize the upslope and downslope geologic hazard features, Table 4 provides counts of the
10 observed feature types and a total geologic hazard features count by section. For a full list of
individual features by section, see Appendix C.
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For Section 1, none of the geologic hazard features above were identified due to heavy vegetation.
However, the slope is a mixed soil and rock slope and signs of rockfall and soil slope failure were
observed along the roadway and the toe of the slope, indicating hazards are likely present.
Table 4. Counts of Observed Geologic Hazard Feature Types by Section
Section Corestone Differential
Erosion
Downslope
Gully Overhang Rock
Package
Root
Wedging Scallop Tree Upslope
Gully
Upslope
Rock
Total
Hazard
Features
1 0 0 0 0 0 0 0 0 0 0 0
2 4 0 3 2 0 0 5 3 0 0 17
3 0 0 0 3 2 0 1 3 0 0 9
4 0 0 1 3 13 0 0 4 0 0 21
5 0 2 1 1 5 0 0 2 1 0 12
6 0 5 2 0 3 2 0 1 2 1 16
7 0 0 0 0 3 0 0 1 0 0 4
8 0 2 0 0 0 0 0 3 1 2 8
9 0 2 2 0 2 0 0 1 0 1 8
10 0 0 1 0 6 0 0 6 2 0 15
11 0 0 2 1 3 2 0 3 1 0 12
Total 4 11 12 10 37 4 6 27 7 4 122
OTHER FEATURES AND CONSIDERATIONS
During our evaluation, we noted additional features other than those specifically related to upslope and
downslope geologic hazards along the roadway. These are briefly summarized in Table 5 below. Table 5
also includes the shorthand symbol assigned to the feature type used to label the features, as shown in
Figures 3 through 13, as well as a reference to an example photo, which has been included in our Photo
Log (Appendix A). A full list of the collected GPS points is included in Appendix B.
Table 5. Other Feature Types
Feature Type
Feature Type Symbol
Description Example Photo (Feature ID)
Boulder Boulder A large boulder on the downslope shoulder located in
Section 3, approximately 19 feet up the road from TP-05.
Photo 11
(Boulder-01)
Culvert Culvert A culvert located in Section 1 along stream leading to
Kaluahine Falls.
Photo 12
(Culvert-01)
Headwall Headwall Three headwalls were observed in our field evaluation. The
walls generally appear to be stabilizing the roadcut slope.
Photo 13
(Headwall-03)
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Headwall 03 appears to have been constructed along with
other roadway improvements, including concrete paving
and a cut or trimmed roadcut outcrop face.
Telephone
Pole
TP Telephone poles are installed on the downslope shoulder
along the roadway. Telephone Pole 08 was observed to be
leaning in the downslope direction.
Photo 14
(TP-08)
Swale SW A constructed berm in the pavement that appears to, or
was intended to, divert surface water to a specific location.
Photo 15
(SW-03)
5 Sections Summaries
The section summaries follow the roadway from the top of the road, at the ranger station, down to the
valley floor at the beach access road. A note for each section has been added on the RHRS score
calculated in our Initial Evaluation. Among the 10 parameters used in the RHRS evaluation, the following
roadway conditions are worth reiterating: (1) along the entire road there is no ditch catchment for rocks
(although occasional drainage swales are present), (2) the roadway width ranges from 11 to 29 feet, and
(3) the sight distance for most of the road is limited. The grade of the road varies between each section
and is calculated for each section.
Each hazard feature has a unique failure mechanism that may act individually or in combination with
other hazards. While some hazards may be more likely to harm roadway users, the identified hazards all
pose a risk to the roadway and traveling public and could cause failure at any time. Due to their
unpredictability, a relative ranking of hazards is not appropriate or useful and our report does not rank
individual hazards by risk. Instead, to provide a measure of “hazard density” that estimates the relative
risk between sections, we have calculated the Hazard to Length Ratio (H:L) for each section. This ratio
was multiplied by 100 and rounded to generate whole number values for easier comparison. The ratio is
used as one of the factors for prioritization of sections.
SECTION 1
Section 1 is in the Upper Area outlined in the Initial Evaluation and is immediately down the roadway
from the ranger station. The alignment of the road includes a sharp curve as the road pushes up against
the slope face. Along the 215-foot length of the road, the elevation changes from ~886 feet to ~864 feet
above mean sea level (MSL), generally yielding a 10% grade. While no hazards were mapped within
Section 1, there is a noted sloughing of soil along the embankment between Station 0+00 and Station
2+15. The heavy vegetation obscures much of the potential sloughing but evidence of outwash and
small cobbles is present along the side of the road. Table 6 summarizes the basic details of Section 1.
Table 6. Section 1 Data Summary
Section Area Start
Station
End
Station
Length
(ft)
Hazard
Count
Hazard-Length
Ratio (H:L)*100
RHRS Score
Upper Area
1 Upper 0+00 2+15 215 0* - 375
* Hazards may be obscured by dense vegetation
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SECTION 2
Section 2 is in the Upper Area outlined in our Initial Evaluation and is a broadly curving section of the
road. Along the 520-foot length of the section, the elevation changes from ~864 feet to ~748 feet MSL,
generally yielding a 22% grade. Within Section 2, a thick layer of saprolite (rock that has weathered to
soil) has formed atop the basalt bedrock. The failure of the saprolite has led to “scallops” of undermined
material remaining on the face of the slope and overhanging root mats of large trees that protrude out
several feet in some cases. Exposed corestones were observed in the face of the upslope in this section
with boulders up to 8 feet in their longest dimension. Along the downslope side of the road, an
ephemeral stream, which leads to Kaluahine Falls, continues to erode a gully that extends beyond the
scope of this investigation. The potential for large-scale landsliding (global instability) along of Section 2
has not been evaluated; however, the conditions observed in the field indicate that the surficial
sloughing may have deeper-seated failure planes. These deep-seated landslide-type failures typically do
not represent an immediate hazard and their evaluation was generally beyond the scope of this work.
Future evaluation of these features may be easier after initial mitigation and clearing work is completed.
To avoid inducing a large-scale failure, any excavation in this area must be limited to removal of surficial
material. We noted a significant downslope gully (DG-10), which appeared to be a shallow landslide,
located down-road from swale SW-12. Table 7 summarizes the basic details of Section 2.
Table 7. Section 2 Data Summary
Section Area Start
Station
End
Station
Length
(ft)
Hazard
Count
Hazard-Length
Ratio (H:L)*100
RHRS Score
Upper Area
Upper 2+15 7+35 520 17 3 375
SECTION 3
Section 3 is in the Central Area outlined in our Initial Evaluation. The alignment of the road in this
section is straight and, along the 415-foot length of the road, the elevation changes from ~748 feet to
~662 feet MSL, generally yielding a 21% grade. Within Section 3, the saprolite becomes less prevalent,
and more competent rock begins to outcrop around Station 11+50. As such, the scallops of saprolite are
less common but discrete zones of rock packages emerge as the most common geologic hazard.
Overhanging trees and their root mats are a hazard throughout Section 3. Table 8 summarizes the basic
details of Section 3.
Table 8. Section 3 Data Summary
Section Area Start
Station
End
Station
Length
(ft)
Hazard
Count
Hazard-Length
Ratio (H:L)*100
RHRS Score
Central Area
3 Central 7+35 11+50 415 9 2 327
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SECTION 4
Section 4 is in the Central Area containing the 2019 downslope landslide feature discussed in our Initial
Evaluation. Section 4 is the longest section. The alignment of the road is a straight corridor and along the
935-foot length of this section, the elevation changes from ~662 feet to ~428 feet MSL, generally
yielding a 25% grade. Within Section 4, trees and overhanging root mats persist but the dominant
hazards are the rock packages stemming from the variations in lava flows, mainly arising from ‘a’
and associated clinker layers. As an example of the combined effects, near Station 13+85 a bench has
formed around a tree causing root wedging, and a void has formed below Tree-08. Along the downslope
side of the road, a gully is forming near Station 15+00 but is difficult to ascertain from the topographic
contours generated in the LiDAR drone survey. Table 9 summarizes the basic details of Section 4.
Table 9. Section 4 Data Summary
Section Area Start
Station
End
Station
Length
(ft)
Hazard
Count
Hazard-Length
Ratio (H:L)*100
RHRS Score
Central Area
4 Central 11+50 20+85 935 21 2 327
SECTION 5
Section 5 is in the Lower Area outlined in our Initial Evaluation. The alignment of this 400-foot section of
road is broadly curving, forming somewhat of an open “z” shape. The elevation changes from ~428 feet
to ~346 feet MSL, generally yielding a 21% grade. Within Section 5, the loose packages of highly
fractured rock continue and differential erosion of the weaker ‘a’
competent rock of the flows. Typical of this differential erosion, near Station 21+30, clinker
was observed weathering out as differential erosion, DE-01. Two discernable gullies have formed,
extending from the upslope to the downslope sides of the road. However, these features are not well
detailed in the topographic contours generated in the LiDAR drone survey. Table 10 summarizes the
basic details of Section 5.
Table 10. Section 5 Data Summary
Section Area Start
Station
End
Station
Length
(ft)
Hazard
Count
Hazard-Length
Ratio (H:L)*100
RHRS Score
Lower Area
5 Lower 20+85 24+85 400 12 3 381
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SECTION 6
Section 6 is in the Lower Area outlined in our Initial Evaluation, and along this 285-foot section of
broadly curving road, the elevation changes from ~346 feet to ~280 feet MSL, generally yielding a
23% grade. Within Section 6, the combined effects of differential erosion, root wedging and rock
packages continue to pose hazards along the road. Extensive root systems are present at Tree-13,
creating a “web”, and exemplifying the ability of roots to infiltrate rock fractures. An area of
fracture-bound rock, RP-23, extends several feet along the crest of the slope and displays signs of recent
rockfall. Also, within Section 6, two observable upslope rock sources, RS-01, were visible from the
roadway. A range finder was used to measure the distance from the downslope edge of pavement (EOP)
to these outcrops, and as a rough measurement, they were found to up ~35 feet and ~60 feet from EOP.
Section 6 also contains a headwall structure, Headwall-03, on the downslope side near Station 24+95.
This structure appears to have been constructed in conjunction with other roadway improvements, but
the engineering properties or purpose were not discernable from the field. Table 11 summarizes the
basic details of Section 6.
Table 11. Section 6 Data Summary
Section Area Start
Station
End
Station
Length
(ft)
Hazard
Count
Hazard-Length
Ratio (H:L)*100
RHRS Score
Lower Area
6 Lower 24+85 27+70 285 16 6 381
SECTION 7
Section 7 is in the Lower Area outlined in our Initial Evaluation. Along this 225-foot section of roadway, a
single tight curve at Station 29+00 separates a steeper gradient from a gentler gradient down-slope of
the station. The total elevation along Section 7 changes from ~280 feet to ~250 feet MSL, generally
yielding a 13% grade. Section 7 continues to see the hazard of rock packages, especially along the crest
of the slope. Section 7 also contains a headwall feature, Headwall-02, near Station 29+25. Again, the
intent of this structure could not be determined from the field work. Table 12 summarizes the basic
details of Section 7.
Table 12. Section 7 Data Summary
Section Area Start
Station
End
Station
Length
(ft)
Hazard
Count
Hazard-Length
Ratio (H:L)*100
RHRS Score
Lower Area
7 Lower 27+70 29+95 225 4 2 381
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SECTION 8
Section 8 is the shortest section in the Lower Area outlined in our Initial Evaluation. Along the 130-foot
length of straight road the elevation changes form ~250 feet to ~218 feet MSL, generally yielding a
25% grade. A surface water flow path, forming upslope and downslope gullies, was noted as an
erosional feature undercutting the roadway and the crest of the slope. These gullies are visible in the
topographic contours, generated from the LiDAR drone survey data, as the “v” shape of the topographic
contours near UG-04 and DG-05. Within Section 8 extensive root structures exacerbate differential
erosion with notable voids forming as seen near DE-07. Table 13 summarizes the basic details of Section
8.
Table 13. Section 8 Data Summary
Section Area Start
Station
End
Station
Length
(ft)
Hazard
Count
Hazard-Length
Ratio (H:L)*100
RHRS Score
Lower Area
8 Lower 29+95 31+25 130 8 6 381
SECTION 9
Section 9 is in the Lower Area outlined in our Initial Evaluation. In this 220-foot length of curving road
the elevation changes from ~218 feet to ~169 feet MSL, generally yielding a 22% grade. Within Section
9, two downslope erosional gullies were noted but no upslope flow path could be attributed to these
features. The topographic contours generated from the LiDAR drone survey data vaguely indicate these
features. Although we did not observe water flowing in this area, surface water being diverted from the
constructed swales may be contributing to these features. Large boulders stemming from a rock source
~80 feet upslope from EOP, RS-04, were observed in the talus of the upslope, and a 10-inch rock was
noted lodged in a tree near Tree-18. The main hazards along the slope face of Section 9 are the
differential erosion and formation of rock packages. Table 14 summarizes the basic details of Section 9.
Table 14. Section 9 Data Summary
Section Area Start
Station
End
Station
Length
(ft)
Hazard
Count
Hazard-Length
Ratio (H:L)*100
RHRS Score
Lower Area
9 Lower 31+25 33+45 220 8 4 381
SECTION 10
Section 10 is in the Lower Area outlined in our Initial Evaluation and is a straight-broadly curving section
of roadway. Along the 290-foot length of road, the elevation changes from ~169 feet to ~101 feet MSL,
generally yielding a 23% grade. Two upslope erosional gullies and a single downslope gully were noted in
Section 10, and the topographic contours, generated from the LiDAR drone survey data, highlight the
paths of water flowing from upslope for UG-03, DG-03, and UG-02. The hazards along the slope face in
Section 10 are columnar rock packages with minor differential erosion along the crest, exacerbated by
heavy tree coverage with extensive root systems. A downed tree, Tree-22, was noted as being a recent
fall in UG-02. A resident passing through at the end of the day confirmed that this tree had fallen the
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morning of 18 May 2022, and that he had moved the fallen tree to the side of the road. Table 15
summarizes the basic details of Section 10.
Table 15. Section 10 Data Summary
Section Area Start
Station
End
Station
Length
(ft)
Hazard
Count
Hazard-Length
Ratio (H:L)*100
RHRS Score
Lower Area
10 Lower 33+45 36+35 290 15 5 381
SECTION 11
Section 11 is in the Lower Area outlined in our Initial Evaluation and is the final section of the road that
was evaluated for hazards. The roadway is another straight-broadly recurving section of the roadway.
Along the 315-foot length of road, the elevation changes from ~101 feet to ~38 feet MSL, generally
yielding a 20% grade. Two downslope erosional gullies were observed, but like Section 9, no upslope
features were attributed to their formation. Again, the diverting of over wash by the constructed swales
may be contributing to DG-01 and DG-02. An upslope erosional gully, UG-01, was observed at the end of
Section 11 but given the intersection of the valley road with the beach access road and the low
elevation, no associated down slope erosional feature was observed. The hazards along the slope face in
Section 11 stem from heavy tree cover and extensive root systems that are inducing root wedging in
rock packages. A slumping root mat was also noted at Tree-26, forming an overhanging feature. Table 16
summarizes the basic details of Section 11.
Table 16. Section 11 Data Summary
Section Area Start
Station
End
Station
Length
(ft)
Hazard
Count
Hazard-Length
Ratio (H:L)*100
RHRS Score
Lower Area
11 Lower 36+35 39+50 315 12 4 381
6 Schema for Section Prioritization and a Phased Approach for Mitigation
The prioritization of sections is based on several factors, with the main factor being the presence of
geologic hazards in each section, as identified in Table 4. However, because of the variability between
the hazards (e.g., hazard type, size, etc.) and the unpredictability of hazards occurring individually or in
combination with others, a simple ratio of the number of mapped hazards in a section to the section’s
length (the H:L ratio) was used as a normalization factor to prioritize sections. Sections with higher
Hazard to Length Ratios have more hazards per linear foot of roadway than do sections with lower
ratios.
The second factor for prioritization includes a level of professional judgement based on field
observations and the geometry of the road itself. Valley Road is steeply graded and narrow,
with sharp curves winding down into the Valley. The steep grade and condition of the pavement
necessitates the use of 4-wheel drive vehicles and slow travel speeds. The combined effect of this
situation is a prolonged exposure to hazards from the upslope face with minimal distance separating the
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travelers and the slope face.Curved sections of the road will be pinch points for traffic and increase the
exposure to hazards.
Lastly,prioritization of sections also considers the cost and feasibility of construction of remedial
measures.To minimize the impact to the public,the level of effort to construct mitigations and the time
expected to undertake the construction must be considered.
Based on the above factors and as requested by the County,we developed a phased mitigation
approach.Table 17 below highlights mitigation of sections based on a prioritized multi phased
construction approach to addressing the numerous hazards along the roadway.The phases were
established based on the factors for the prioritization schema to facilitate the quick response sought by
the County.This approach would first address areas that may not require a specialty contractor for
construction,followed by phases of construction that will require prolonged road closures and specialty
construction to mitigate the higher risk features.Specifications and provisions for the appropriate
qualifications of a contractor will be included in the design package.
Phase 1:This phase would include the mechanical excavation of scallop features within the saprolitic
material,minor rock packages,root mats,tree removal,and general vegetation clearing within
Sections 1 and 2.This work can best be described as hazards removal/excavation and is intended to
address areas that pose less risk than others and require less time to conduct the mitigation.Where
feasible,the County should also clean out and re establish surface drainage features,such as roadside
ditches and diversion berms,so that water is not directed in an uncontrolled manner over slopes.
Phase 2:This phase would consist of mitigation of the slope faces,including scaling loose debris and
rock packages,and the installation of draped mesh.Scaling is expected to be undertaken across the
entire slope face and will likely extend upslope as deemed necessary for the safety of construction
crews.However,it is preferred to limit upslope disturbance beyond the immediate slope face adjacent
to the roadway,as any disturbance may increase the limits of mesh installation or necessitate the need
for other remediation such as dowel installation,shotcrete,or additional barriers.
As the mitigation style for hazards in Phase 2 varies depending on the co occurrence of hazards,a
further prioritization of sections in this phase was required.At this point,the Hazard to Length Ratio was
added to the consideration for level of effort during construction and judgement based on the subject
matter experts’field observations to group sections of higher concern into subphases 2A through 2D,
ranked from highest priority to lowest priority,respectively.
Subphase 2A includes Sections 7,8,and 9 and will focus on scaling rock packages and erosional
features exacerbated by root wedging,as well as installation of a draped mesh to contain
further rockfall and sloughing overburden from reaching the road.
Subphase 2B includes Sections 10 and 11 and will focus on scaling columns of rock packages and
removal of extensive root structures and any rock attached,especially along the crest of the
slope face.Tree removal will uncover new packages of loose rock,which will also need to be
scaled.Installation of draped mesh to avoid excessive upslope disturbance is expected for much
of Section 10 and into Section 11.
Valley Road Evaluation Project
30 September 2022
Page 13
Subphase 2C includes Sections 5 and 6 and will focus on scaling highly fractured rock packages
along the crest of the slope and addressing the effects of differential erosion stemming from the
variation in lava flows. Removal of trees causing extensive root jacking will dislodge additional
rocks, which will need to be removed with minimal upslope disturbance. A rockfall attenuation
fence is proposed to be installed in Section 6 (in Phase 3) and may necessitate the need to
extend the mesh further down station to approximately Station 27+50.
Subphase 2D includes Sections 3 and 4 and will focus on the removal of saprolitic material that
was unable to be removed in Phase 1. The transition from saprolite to competent rock in Section
3 is expected to require light scaling to avoid the creation of undermined slope conditions.
Overhang removal will need to limit disturbance to the upper slope and the scaling of
differentially eroded rock packages will need to be light to not create any further undermined
areas.
It is important to note that the limits for mesh installation are approximate and will be refined during
final design. For this reason, Figures 14 through 24, Mitigation Features, are not strictly intended to
approximate limits of installation but rather to identify the general area of coverage for the slope face in
developing an estimate for cost of installation.
Phase 3: This phase includes the installation of rockfall impact fence systems in Sections 6, 8, and 9. The
fences are intended to prevent rockfall from the observed upslope rock sources from reaching the
roadway. Installation of the fences during this phase are broken out as a separate phase as a time
consideration for prolonged construction. The approximate delineation of the impact fences is marked
in Figures 19, 21, and 22. As access to the upper slope is expected to be difficult, this phase of
construction is more intensive than the other Phases. However, the sections requiring impact fence
systems will also be worked on in Phase 2, thus Phase 3 may be combined with the work of Phase 2 to
save on mobilization costs, should the County wish to do so. Furthermore, the recommended limits of
impact fences may be refined during the Phase 2 work based on conditions exposed during vegetation
clearing and grubbing, as well as rock scaling.
In general, all construction operations should be completed under the direction of an engineer or
geologist with professional experience in rockfall and slope hazard remediation. Tree removal including
root systems and overburden along the crest of the slope should be addressed at the beginning of each
construction phase.
Valley Road Evaluation Project
30 September 2022
Page 14
7 Mitigation Phasing Summary
Based on our evaluation, multiple geologic hazards are present along the Valley Road study area
that pose risk to the traveling public. We have classified the road into differing geologic hazard sections
and summarized likely mitigation scopes and costs for these areas. A three-phase approach for the
remediation of these hazards is proposed based on a prioritization of sections and the desire to
remediate the more easily constructed Sections followed by Sections prioritized by highest hazard risk.
The remediation approaches vary between each phase but are expected to include excavation of
surficial soil and rock, hand scaling of loose rock and saprolitic material, installation of draped mesh
systems to retain rock falling from the face of the slope, and a series of rockfall impact fences intended
to stop rockfalls stemming from upslope rock sources. Table 17 provides a summary of the proposed
phases and scopes of mitigation work along the roadway.
Table 17. Mitigation Phasing Summary
Construction
Mitigation
Phase
Section(s)/
Subgroups Mitigation Type(s)
Area of
Slope
Addressed
Description of Work Estimated
Duration1
Phase 1 –
General
Excavation
1, 2 Hazards Removal by
Excavation
Saprolitic
areas along
Slope Face
Remove scallops,
loose material, trim
root mats, and cut
trees
5 Weeks
Phase 2 – Rock
Stabilization
2A - 7, 8, 9
2B - 10, 11
2C - 5, 6
2D -3, 4
Hazards Removal by
Rock Scaling &
Installation of Draped
Mesh
Slope Face
and Crest
Scale loose Rock
Packages and install
draped mesh as
needed
57 Weeks
Phase 3 –
Rockfall
Attenuation
6, 8, 9 Rockfall Attenuator
Fence Systems
Upslope
Rock Source
Areas
Install rockfall impact
fence systems 48 Weeks
1 The Estimated Durations only includes active construction and does not include support activities such as materials acquisition,
mobilization, demobilization, etc.
In addition to the work outlined in Table 17, rock dowel installation may be utilized as a precaution if
construction destabilizes an area not able to be remediated by scaling or mesh alone. The specifications
and design of the dowels will be based on observed rock sizes and models of rockfall in the design
phase. Design of the draped mesh and impact fence systems will require further calculations and
modeling to establish limits of absorption. Proprietary design of mesh systems varies between each
manufacturer and a final design for material properties will be based on criteria provided by us,
although will require a stamped design from the contractor’s engineer.
Valley Road Evaluation Project
30 September 2022
Page 15
8 Schedule and Duration
The County has requested estimated durations for the proposed phases and subphases. The durations
by section were estimated using the approximated section mitigation lengths and coverages, and then
were compared to similar types of recent local Haley & Aldrich projects. The estimated durations have
been provided in weeks and include only active construction and do not include support activities such
as materials acquisition, mobilization, demobilization, etc. Table 17 above provides a summary of the
estimated duration of each Phase of work, and Table 18 below provides an estimated duration in weeks
for by each phase, subphase, and section.
Table 18. Estimated Minimum Durations in Weeks
Phase Subphase Section(s) Estimated Minimum
Duration1 (Weeks)
Phase 1 1 1 1
Phase 1 1 2 4
Phase 1 Subtotal 5
Phase 2 2A 7 6
Phase 2 2A 8 6
Phase 2 2A 9 6
Phase 2 2B 10 6
Phase 2 2B 11 6
Phase 2 2C 5 6
Phase 2 2C 6 6
Phase 2 2D 3 3
Phase 2 2D 4 4
Phase 2 Subtotal 49
Phase 3 3 6 19
Phase 3 3 8 16
Phase 3 3 9 13
Phase 3 Subtotal 48
1 The Estimated Durations include only active construction and does not include support activities such as materials
acquisition, mobilization, demobilization, permitting, etc.
Valley Road Evaluation Project
30 September 2022
Page 16
9 Cost Estimates
To estimate mitigation costs where sufficient information was available, we considered typical
mitigation methods for each hazard and what the most likely method would be at each section. We
concluded that the following methods of mitigation would most likely be required to address the
identified hazard areas.
MECHANICAL EXCAVATION
As discussed in our Initial Evaluation, mechanical excavation of the slope would remove the loose rock,
soil, and overhanging trees posing a risk above or adjacent to the roadway. The soil and rock mass
adjacent to the roadway can be removed by using conventional excavating equipment if the rock mass is
highly weathered and “rippable.” This type of work is highly invasive and has the potential to create
larger issues if care is not taken. Unit prices of $2 to $5 per square foot were used in our cost estimates.
ROCK SCALING
As discussed in our Initial Evaluation, rock scaling is the procedure of removing loose rocks from the
hillside and cliff face. Scaling is not considered a permanent mitigation and would typically need to be
conducted every 5 to 10 years to maintain its effectiveness, dependent on the site. Scaling should not be
considered as reliable as structural methods since there is typically some subjectivity in selecting which
rocks to remove. In addition, it is not always apparent what rocks are likely to fail within a specific
period. Scaling can be conducted mechanically if equipment can safely reach the specific rock areas from
the roadway (e.g., overhangs directly adjacent to the road), though scaling is often done by hand by
workers rappelling down the cliff face and prying rocks loose. Unit prices of $6 to $13 per square foot
were used in our cost estimates.
DRAPERY NETTING
As discussed in our Initial Evaluation, rockfall drapery netting consists of high strength steel fabric, laid
over the slope/source area and connected to the slope by cables and rock bolts that are usually installed
along the top of the cliff. Generally, a fallout area is included in the design and the netting placed to
allow rocks to drop behind the netting into the fallout area at the base of the cliff/source. This allows for
maintenance/removal of rocks as needed and maintains the useful life of the netting.
Rockfall netting is designed based on rock size, slope gradient, and area covered. Netting is selected that
can control rocks of the size expected to be generated from the specific site. The netting and anchorage
must also be of sufficient strength to support the weight of rocks that might lodge between the slope
and netting, along with its own weight, a function of the slope gradient, as well as the dimensions of the
area netted. Since netting is typically more expensive than fencing and more difficult to install, netting is
typically used only where site conditions do not provide sufficient room for fence installation, such as
along narrow stretches of the Lower Section of Waipi‘o Valley Road.
Drapery netting is the most economical measure where an adequate ditch is already located at the base
of the slope, so drapery netting was selected for such locations. If there is no ditch, a ditch may be
constructed where there is adequate shoulder space or routine monitoring and maintenance would
Valley Road Evaluation Project
30 September 2022
Page 17
need to be performed. Unit prices of $8 to $20 per square foot were used in our cost estimates. A
conceptual design detail for Drapery Netting is shown on Figure 25.
ROCKFALL IMPACT FENCE
As discussed in our Initial Evaluation, rockfall fences consist of high-strength fences installed at the toe
of a slope to “catch” falling rocks. The fences are manufactured from steel components that have
built-in energy dissipation/absorption capabilities. Typically, steel rings and sacrificial components are
integrated into the fencing, which deform elastically and then plastically to stop rocks that impact the
fence. The fences are generally constructed of posts that are connected to concrete footings or placed
into concrete filled holes (where rock is present at the surface). The posts are guyed together laterally,
and often in the upslope direction with steel cables. High-strength steel fabric runs between the posts
and is the primary element that the rock impacts. The rock energy is transferred to the fabric, which
transfers it to the posts, cables, and ground anchors/foundations. Some energy is also dissipated by
plastic deformation of the rockfall fence components.
Rockfall fencing is designed based on three main characteristics: rock impact energy, rock bounce
height, and site soil conditions. Rock impact energy and bounce height were estimated from the
computer program RocFall, as noted in Section 4.3 of the Initial Evaluation. Foundation conditions were
not determined under the scope of this report but would be determined as part of additional work if
fencing is selected as a mitigation strategy. Additionally, precise fence locations and lengths will need to
be determined in the design phase, which may affect the estimated lengths provided in this cost
estimate. Unit prices of $800 to $4,500 per linear foot were used in our cost estimates. A conceptual
design detail for a Rockfall Impact Fence is shown on Figure 25.
ROCK BOLTING
As discussed in our Initial Evaluation, localized stabilization methods target rockfall source zones and
include rock dowels, cable lashing, shotcrete, and anchored netting systems. Rock dowels are fully
grouted steel bars that are not post-tensioned and secure specific unstable rock blocks. Cable lashing
systems typically use wire rope to stabilize rock blocks that cannot be doweled. Shotcrete (concrete
propelled by a nozzle) can stabilize shear zones or highly weathered and fractured rock masses and are
often paired with dowels or anchors. Anchored netting with erosion control matting, which is secured by
boundary cables, cable anchors and patterned or targeted soil nails/rock dowels, can be used on
combination soil and rock slopes or larger fractured rock masses. These methods would likely be used in
conjunction with other mitigation methods.
Individual rock bolting, lashing or other measures may be necessary in lieu of or to supplement netting,
but determining the need for such measures would require additional consideration. Unit prices of
$5,000 to $6,500 each would be anticipated, but cost estimates could not be developed for these
measures at this conceptual stage and were not included in the cost estimates matrix below. Provisions
for rock bolting, lashing, or other measures for incidental rock stabilization will be considered in the
project plans and specifications.
Waipi o Valley Road Evaluation Project
30 September 2022
Page 18
OTHER NON GEOLOGIC ROADWAY IMPROVEMENTS
Surface drainage improvements and road realignment costs are not included in the cost estimates
below; however, the County may want to consider additional non geologic roadway improvements,
such as, widening, striping, grade changes, guardrails, vertical and horizontal alignment changes.
SUMMARY OF COSTS
Appendix D details the estimated costs for rockfall mitigation. Mitigation costs for other hazards could
not be characterized sufficiently to allow for a reasonable estimation of costs at this conceptual stage.
We appreciate the opportunity to support the County of Hawai’i on the Waipi o Valley Road project.
Please contact us if you have any questions.
Sincerely yours,
HALEY & ALDRICH, INC.
Christopher M. Eddy
Technical Specialist
Daniel Trisler, P.E.
Principal Geotechnical Engineer
Attachments:
Figure 1 – Project Locus
Figure 2 – Site Plan
Figures 3 through 13 – Sections Figures – Site Features
Figures 14 through 24 – Sections Figures – Mitigation Features
Figure 25 – Conceptual Details
Appendix A – Photo Log
AppendixB–GPSFieldData
Appendix C – Features Data by Section
Appendix D – Rockfall Mitigation Measures and Estimated Costs by Section
\\haleyaldrich.com\share\pdx_data\Notebooks\0203303 001_Waipio_Valley_Geotechnical_Design\Deliverables\Reports\Waipio Valley Road
Phase 1 Final\2022_0930_HAI_Waipio Valley Road Phase 1_F.docx
Daniel Trisler,P.E.
FIGURES
SITE
155°35'0"W155°36'0"W155°37'0"W155°38'0"W
20°8'0"N
20°7'0"N
20°6'0"N
20°5'0"N
20°4'0"N
GIS: \\haleyaldrich.com\share\pdx_data\Notebooks\0203303-001_Waipio_Valley_Geotechnical_Design\GIS\Maps\2022_07\203303_001_0001_PROJECT_LOCUS.mxd - khaskins - 7/1/2022 2:31:57 PMMAP SOURCE: ESRISITE COORDINATES: 20°06'54"N, 155°35'29"W
WAIPIO VALLEY ROAD EVALUATIONHONOKAA, HAWAII
PROJECT LOCUS
FIGURE 1APPROXIMATE SCALE: 1 IN = 4000 FT 2022
BASE MAP SERVICES
Ideal scales forsite vincity figures
1 : 108,000Scale bar = 4 miles
1 : 54,000Scale bar = 2 miles
1 : 24,000 (default)
1 : 13,500Scale bar = 0.5 mile
HI
500
550600650700750
800
850
900
50
150
200
250
300
350
400
300
350
400450
500 550600650700[][][]
[][]
[]
[][]
[]
[][][][][][][][][][][][][]
SET M
AG
N
A
IL
466,41
6
.0
8
N
OR
TH
1,611,
5
39
.
08
EA
STELEV.=8
81
.
25
E
E
E
E
0+00
1+002+003+004
+
0
0
5+0
0
6+00
7+00
8+00
9+00
10+0
0
11+0
0
12+0
0
13+0
0
14+0
0
15+0
0
16+00
17+00
18+0
0
19+0
0
20+0
0
21+0022+0023+00
24+0025+0
0
26+00
27+0028+0
0
29+00
30+0
0
31+00
32+0033+00
34+0035+0036+0
0
37+00
38+0
0
39+0039+67.54
FIGURE 13
FIGURE 12
FIGURE 11 FIGURE 10
FIGURE 7
FIGURE 6
FIGURE 5
FIGURE 4
FIGURE 3
FIGURE 9
FIGURE 8
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0002_SITE_PLAN.DWGSLIVNYAK, OLEG00029/30/2022 4:38 PMLayout:Printed:FIGURE 2
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SITE PLAN
SCALE: AS SHOWN
SEPTEMBER 2022
0 150 300 450 600
SCALE IN FEET
LEGEND
EDGE OF ROAD
GUARD RAIL
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
NOTES
1.ACCURACY FOR GPS POINT AND LINE FEATURES WERE LIMITED DUE TO
POOR SATELLITE CONNECTIVITY RELATED TO TOPOGRAPHIC AND
VEGETATIVE OBSTRUCTIONS ALONG THE ROADWAY. THUS, GPS
FEATURE LOCATIONS ARE APPROXIMATE AND NOT INTENDED FOR
SURVEY OR CONSTRUCTION USE.
2.DUE TO LIMITED ACCURACY FOR GPS LINE FEATURES CAPTURED IN THE
FIELD, GPS LINE FEATURES WERE SIMPLIFIED TO BE SHOWN AS LINES
APPROXIMATELY PARALLEL TO THE ROADWAY ALIGNMENT CENTERLINE
WITH START AND END POINT TAKEN FROM THE ORIGINAL LINE.
3.SEE TABLES 2, 3, AND 5 IN REPORT FOR ACRONYM DEFINITIONS.
[]
870
880
89
0
900
910
920
860
870
880
890
900
840
850
860
87
0
880
890
900
840850860870870880[][][][][][][][][][][][][][][][][][][][][][][][][][][]
[][][][][][]
[]
[]
[][][][][][][][]SET MAG NAIL
466,416.08 NORTH
1,611,539.08 EAST
ELEV.=881.25
STATION=0+00.00
OFFSET=0.00
NORTHING=466437.15
EASTING=1611567.73
SECTION-01 START
SECTION-01 END
0+
0
0
0+50
1+00
1+50
2
+
0
0
2+50
3+00
3+50
STATION=0+32.23
OFFSET=9.54R
NORTHING=466416.08
EASTING=1611539.08
UTILITY POLE, TYP.
GUARD RAIL, TYP.
EDGE OF ROAD, TYP.
S02U
SW-14
TP-1
GC-1
SW-15
Culvert-Outlet
Culvert-InletS01L
S01U
CS-1
CS-2
OH-1
STATION=2+15.00
OFFSET=0.00
NORTHING=466246.78
EASTING=1611509.29
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0003_0013_RHRS_GPS.DWGSLIVNYAK, OLEGSECTION-019/30/2022 4:38 PMLayout:Printed:FIGURE 3
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION1 SITE FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 10 20 30 40
SCALE IN FEET
NOTES
1. ACCURACY FOR GPS POINT AND LINE FEATURES WERE LIMITED
DUE TO POOR SATELLITE CONNECTIVITY RELATED TO
TOPOGRAPHIC AND VEGETATIVE OBSTRUCTIONS ALONG THE
ROADWAY. THUS, GPS FEATURE LOCATIONS ARE APPROXIMATE
AND NOT INTENDED FOR SURVEY OR CONSTRUCTION USE.
2. DUE TO LIMITED ACCURACY FOR GPS LINE FEATURES
CAPTURED IN THE FIELD, GPS LINE FEATURES WERE SIMPLIFIED
TO BE SHOWN AS LINES APPROXIMATELY PARALLEL TO THE
ROADWAY ALIGNMENT CENTERLINE WITH START AND END
POINT TAKEN FROM THE ORIGINAL LINE.
3. SEE TABLES 2, 3, AND 5 IN REPORT FOR ACRONYM DEFINITIONS.
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
GPS POINTS
ADJUSTED GPS POINTS
GPS TRAVERSE LINES
UPSLOPE ROCK SOURCE
[]
MATCHLINE - SEE SHEET 4
87088089090091092086087088089090084
0850860870880890900840
850
860
870
870
880 7207307407507
6
0770780790800810820830840850860870880890900
770
770
780
780
790
790
800
800
810
810
820
820
830
840
850
860
870
880
890
900
910
[][][][][][][
][][][][][][
][][][][][][][][][][][][]SET MAG NAIL466,416.08 NORTH1,611,539.08 EASTELEV.=881.25SC-4
0+000+501+001+502+002+503+003+
5
0
4+00
4+50
5+00 5+50
6+00 6+507+007+508+008+50SECTION-02 START
SECTION-02 END
GUARD RAIL, TYP.
STATION=2+15.92
OFFSET=0.00
NORTHING=466247.20
EASTING=1611508.47
EDGE OF ROAD, TYP.
S02U
CS-3
TP-3
SW-12
TP-2
SW-11
SW-13
DG-10
DG-11
DG-12
SW-14
TP-1
GC-1
SW-15
Culvert-Outlet
Culvert-Inlet
S01L
S01U
S02L
CS-1
CS-2
SC-1
CS-4
Tree-1
Tree-2
Tree-3
S03U
SC-6
Tree-4
Tree-5
Tree-6
OH-3RP-1
OH-2
SC-5SC-4
SC-3SC-2
OH-1
STATION=7+35.00
OFFSET=0.00
NORTHING=466426.33
EASTING=1611132.67
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0003_0013_RHRS_GPS.DWGSLIVNYAK, OLEGSECTION-029/30/2022 4:38 PMLayout:Printed:FIGURE 4
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION2 SITE FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 20 40 60 80
SCALE IN FEET
NOTES
1. ACCURACY FOR GPS POINT AND LINE FEATURES WERE LIMITED
DUE TO POOR SATELLITE CONNECTIVITY RELATED TO
TOPOGRAPHIC AND VEGETATIVE OBSTRUCTIONS ALONG THE
ROADWAY. THUS, GPS FEATURE LOCATIONS ARE APPROXIMATE
AND NOT INTENDED FOR SURVEY OR CONSTRUCTION USE.
2. DUE TO LIMITED ACCURACY FOR GPS LINE FEATURES
CAPTURED IN THE FIELD, GPS LINE FEATURES WERE SIMPLIFIED
TO BE SHOWN AS LINES APPROXIMATELY PARALLEL TO THE
ROADWAY ALIGNMENT CENTERLINE WITH START AND END
POINT TAKEN FROM THE ORIGINAL LINE.
3. SEE TABLES 2, 3, AND 5 IN REPORT FOR ACRONYM DEFINITIONS.
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
GPS POINTS
ADJUSTED GPS POINTS
GPS TRAVERSE LINES
UPSLOPE ROCK SOURCE
CONCRETE[]
MATCHLINE - SEE SHEET 3
MATCHLINE - SEE SHEET 5
600
610
620
630
640
650
660
670
680
690
70
0
71
0
72
0
730
740
750
760
770
780
790
800
810
820
830
840
850
640
650
660
670
680
690
720
730
740
750 760770
78
0
79
0
80
0
810
820
830
6+00
6+
5
0
7+
0
0
7+
5
0
8+
0
0
8+
5
0
9+
0
0
9+5
0
10+
0
0
10+
5
0
11+
0
0
11
+
5
0
12
+
0
0
SECTION-03 END
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
SET MAG NAIL
STATION=11+16.15
OFFSET=7.02R
NORTHING=466233.63
EASTING=1610803.31 TP-5
Boulder
GC-2
SW-9
TP-4
SW-10
TP-3
SW-12
SW-11
DG-10
S02L
Tree-1
Tree-2
Tree-3
S03U
SC-6
Tree-4 Tree-5
Tree-6
RP-2
S03L
S04U RP-3
RP-4
OH-6
OH-5
OH-4
OH-3
RP-1
OH-2
SC-5
STATION=7+35.00
OFFSET=0.00
NORTHING=466426.33
EASTING=1611132.67
SECTION-03 START
STATION=11+50.00
OFFSET=0.00
NORTHING=466209.28
EASTING=1610781.27
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0003_0013_RHRS_GPS.DWGSLIVNYAK, OLEGSECTION-039/30/2022 4:38 PMLayout:Printed:FIGURE 5
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION3 SITE FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 20 40 60 80
SCALE IN FEET
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
GPS POINTS
ADJUSTED GPS POINTS
GPS TRAVERSE LINES
UPSLOPE ROCK SOURCE
CONCRETE
NOTES
1. ACCURACY FOR GPS POINT AND LINE FEATURES WERE LIMITED
DUE TO POOR SATELLITE CONNECTIVITY RELATED TO
TOPOGRAPHIC AND VEGETATIVE OBSTRUCTIONS ALONG THE
ROADWAY. THUS, GPS FEATURE LOCATIONS ARE APPROXIMATE
AND NOT INTENDED FOR SURVEY OR CONSTRUCTION USE.
2. DUE TO LIMITED ACCURACY FOR GPS LINE FEATURES
CAPTURED IN THE FIELD, GPS LINE FEATURES WERE SIMPLIFIED
TO BE SHOWN AS LINES APPROXIMATELY PARALLEL TO THE
ROADWAY ALIGNMENT CENTERLINE WITH START AND END
POINT TAKEN FROM THE ORIGINAL LINE.
3. SEE TABLES 2, 3, AND 5 IN REPORT FOR ACRONYM DEFINITIONS.
[]
MATCHLINE - SEE SHEET 4
MATCHLINE - SEE SHEET 6
370
380
390
400
410
420
430
440
450
460470
480
490
500
510
520
530 540550
560
570
580
590
600
610
620
630
640
650
660
670
680
690
700
710
720
730
740
750
760
400
410
42
0
430
440
450
460
470
480
490
500
510
520
530
540
550
560
570
580
590
600
610
620
630
640
560
570
580
590
600
610
620
630
640
65
0
660
670
680
690
700
710
720
730
740
750
[][][][][][]EEEEEEEEEEEEEEEEEEEEEE11+
0
0
11
+
5
0
12
+
0
0
12+
5
0
13+
0
0
13+
5
0
14+
0
0
14+
5
0
15
+
0
0
15
+
5
0
16
+
0
0
16+
5
0
17+0
0
17+5
0
18+0
0
18+
5
0
19
+
0
0
19
+
5
0
20+
0
0
20+
5
0
21+00
SET MAG NAIL
SECTION-04 START
SECTION-04 END
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
GUARD RAIL, TYP.
HIGH TENSION OVERHEAD WIRE
STATION=11+16.15
OFFSET=7.02R
NORTHING=466233.63
EASTING=1610803.31
STATION=20+84.54
OFFSET=0.30R
NORTHING=465687.31
EASTING=1610011.35
DG-9
TP-9
SW-1
SW-2
SW-3
SW-4
TP-8
GC-3
SW-5
SW-6
TP-7
Tree-7
SW-7
TP-6
SW-8
TP-5
Boulder
GC-2
SW-9
RP-14
S03L
S04U RP-3
RP-5
RP-6
RP-7
RP-8
RP-9
Tree-8
Tree-9
RP-13
RP-15
Tree-10 S04L
S05U
RP-16
RP-12
OH-8
RP-11
RP-10
OH-7
RP-4
OH-6
OH-5 STATION=11+50.00
OFFSET=0.00
NORTHING=466209.28
EASTING=1610781.27
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0003_0013_RHRS_GPS.DWGSLIVNYAK, OLEGSECTION-049/30/2022 4:38 PMLayout:Printed:FIGURE 6
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION4 SITE FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 30 60 90 120
SCALE IN FEET
NOTES
1. ACCURACY FOR GPS POINT AND LINE FEATURES WERE LIMITED
DUE TO POOR SATELLITE CONNECTIVITY RELATED TO
TOPOGRAPHIC AND VEGETATIVE OBSTRUCTIONS ALONG THE
ROADWAY. THUS, GPS FEATURE LOCATIONS ARE APPROXIMATE
AND NOT INTENDED FOR SURVEY OR CONSTRUCTION USE.
2. DUE TO LIMITED ACCURACY FOR GPS LINE FEATURES
CAPTURED IN THE FIELD, GPS LINE FEATURES WERE SIMPLIFIED
TO BE SHOWN AS LINES APPROXIMATELY PARALLEL TO THE
ROADWAY ALIGNMENT CENTERLINE WITH START AND END
POINT TAKEN FROM THE ORIGINAL LINE.
3. SEE TABLES 2, 3, AND 5 IN REPORT FOR ACRONYM DEFINITIONS.
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
GPS POINTS
ADJUSTED GPS POINTS
GPS TRAVERSE LINES
UPSLOPE ROCK SOURCE
CONCRETE[]
MATCHLINE - SEE SHEET 5
MATCHLINE - SEE SHEET 7
30
0
310
3
3
0
3
4
0
3
5
0
3
6
0
37
0
240
250
260
27
0
28
0
300
31
0
330
34
0
35
0
36
0
3
7
0
3
8
0
390
40
0
410
42
0
430
440
450
46
0
300
310
330
340
350
360
370
380
390
400
410
420
430
440
450
460
470
48
0
49
0
500
51
0
520
5
3
0
36
0
37
0
380
390
400
410
4
2
0
430
440
450
46
0
470
480
490
50
0
510
23
0
24
0
2
5
0
26
0
270
280
300
310
330
340
350
360
370
380
3
9
0
4
0
0
4
1
0
4
2
0
43
0
44
0
4
5
0
4
6
0 4704
8
0
4
9
0
500
5
1
0
520
530
540
[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]EEEEEE1
9
+
5
0
20
+
0
0
20
+
5
0
21+00
21+50
22+
0
0
22
+
5
0
2
3
+
0
0
23+
5
0
24+00
24
+
5
0
25
+
0
0
25+
5
0
2
6
+
0
0
STATION=20+84.05
OFFSET=0.00
NORTHING=465687.56
EASTING=1610011.87
STATION=22+85.56
OFFSET=8.89R
NORTHING=465549.70
EASTING=1609879.38
TP11
DG-7
UG-6
Headwall-3
TP-10
GC-4
DG-8
UG-7
TP-9
SW-1
SW-2
RP-14
Tree-13
Tree-9
RP-15
Tree-10
S04L
S05U
RP-16
DE-1
Tree-11
Tree-12
RP-17
RP-20
S05L
S06U DE-3
RP-21
RW-1
DE-4
RW-2
DE-5
DE-2
RP-19
RP-18
OH-9
STATION=24+85.00
OFFSET=0.00
NORTHING=465406.11
EASTING=1609746.10
SECTION-05 END
SECTION-05 START
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
SET MAG NAIL
GUARD RAIL, TYP.\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0003_0013_RHRS_GPS.DWGSLIVNYAK, OLEGSECTION-059/30/2022 4:38 PMLayout:Printed:FIGURE 7
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION5 SITE FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 20 40 60 80
SCALE IN FEET
NOTES
1. ACCURACY FOR GPS POINT AND LINE FEATURES WERE LIMITED
DUE TO POOR SATELLITE CONNECTIVITY RELATED TO
TOPOGRAPHIC AND VEGETATIVE OBSTRUCTIONS ALONG THE
ROADWAY. THUS, GPS FEATURE LOCATIONS ARE APPROXIMATE
AND NOT INTENDED FOR SURVEY OR CONSTRUCTION USE.
2. DUE TO LIMITED ACCURACY FOR GPS LINE FEATURES
CAPTURED IN THE FIELD, GPS LINE FEATURES WERE SIMPLIFIED
TO BE SHOWN AS LINES APPROXIMATELY PARALLEL TO THE
ROADWAY ALIGNMENT CENTERLINE WITH START AND END
POINT TAKEN FROM THE ORIGINAL LINE.
3. SEE TABLES 2, 3, AND 5 IN REPORT FOR ACRONYM DEFINITIONS.
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
GPS POINTS
ADJUSTED GPS POINTS
GPS TRAVERSE LINES
UPSLOPE ROCK SOURCE
CONCRETE[]
MATCHLINE - SEE SHEET 6
MATCHLINE - SEE SHEET 8
220
230
240
250
260
270
280
300
310
260
270
280
300
310
330
340
350
360
370
380
390
400
410
420
300
310
330
340
350
360
370
380
390
400
410
420
430
440
450
460
[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]25+00
25+50
26+00
26+50
27+00
27+50
SECTION-06 START
SECTION-06 END
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
GUARD RAIL, TYP.
TP11
DG-7
UG-6
DG-6
UG-5
Headwall-3
Tree-13
S05L
S06U
DE-3 RP-21
RW-1
DE-4
RW-2
DE-5
RP-22
DE-6
S06L
S07U
RP-24
RS-1
RP-23
DE-2
STATION=24+85.00
OFFSET=0.00
NORTHING=465406.11
EASTING=1609746.10
STATION=27+70.00
OFFSET=0.00
NORTHING=465225.90
EASTING=1609535.83
RS-1
RS-1
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0003_0013_RHRS_GPS.DWGSLIVNYAK, OLEGSECTION-069/30/2022 4:38 PMLayout:Printed:FIGURE 8
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION6 SITE FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 10 20 30 40
SCALE IN FEET
NOTES
1. ACCURACY FOR GPS POINT AND LINE FEATURES WERE LIMITED
DUE TO POOR SATELLITE CONNECTIVITY RELATED TO
TOPOGRAPHIC AND VEGETATIVE OBSTRUCTIONS ALONG THE
ROADWAY. THUS, GPS FEATURE LOCATIONS ARE APPROXIMATE
AND NOT INTENDED FOR SURVEY OR CONSTRUCTION USE.
2. DUE TO LIMITED ACCURACY FOR GPS LINE FEATURES
CAPTURED IN THE FIELD, GPS LINE FEATURES WERE SIMPLIFIED
TO BE SHOWN AS LINES APPROXIMATELY PARALLEL TO THE
ROADWAY ALIGNMENT CENTERLINE WITH START AND END
POINT TAKEN FROM THE ORIGINAL LINE.
3. SEE TABLES 2, 3, AND 5 IN REPORT FOR ACRONYM DEFINITIONS.
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
GPS POINTS
ADJUSTED GPS POINTS
GPS TRAVERSE LINES
UPSLOPE ROCK SOURCE
CONCRETE[]
MATCHLINE - SEE SHEET 7
MATCHLINE - SEE SHEET 9
17
0
180
20
0
220
230
24
0
25
0
26
0
270
280
30
0
310
330
34
0
350
360
370
170
180
200
220
230
240
250
260
270
280
300
310
330
340
350
360
370
380
[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]27+50
28+00
28+50
29+00
29
+
5
0
30+00
30+5
0
SECTION-07 START
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
GUARD RAIL, TYP.
SECTION-07 END
TP-13
Headwall-2
TP12
RP-26
Tree-14
S06L
S07U
RP-25
RP-24
S08U
S07L
Tree-15
Tree-16 RS-2
DE-7
RS-1
STATION=27+70.00
OFFSET=0.00
NORTHING=465225.90
EASTING=1609535.83
STATION=29+95.00
OFFSET=0.00
NORTHING=465130.19
EASTING=1609343.83
RS-1
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0003_0013_RHRS_GPS.DWGSLIVNYAK, OLEGSECTION-079/30/2022 4:39 PMLayout:Printed:FIGURE 9
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION7 SITE FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 10 20 30 40
SCALE IN FEET
NOTES
1. ACCURACY FOR GPS POINT AND LINE FEATURES WERE LIMITED
DUE TO POOR SATELLITE CONNECTIVITY RELATED TO
TOPOGRAPHIC AND VEGETATIVE OBSTRUCTIONS ALONG THE
ROADWAY. THUS, GPS FEATURE LOCATIONS ARE APPROXIMATE
AND NOT INTENDED FOR SURVEY OR CONSTRUCTION USE.
2. DUE TO LIMITED ACCURACY FOR GPS LINE FEATURES
CAPTURED IN THE FIELD, GPS LINE FEATURES WERE SIMPLIFIED
TO BE SHOWN AS LINES APPROXIMATELY PARALLEL TO THE
ROADWAY ALIGNMENT CENTERLINE WITH START AND END
POINT TAKEN FROM THE ORIGINAL LINE.
3. SEE TABLES 2, 3, AND 5 IN REPORT FOR ACRONYM DEFINITIONS.
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
GPS POINTS
ADJUSTED GPS POINTS
GPS TRAVERSE LINES
UPSLOPE ROCK SOURCE
CONCRETE[]
MATCHLINE - SEE SHEET 8
MATCHLINE - SEE SHEET 10
170
180
200220
230
240
250
260
270
280
300
310
170
180
200
220
230
240
250
260
270
280
300
310
330
340
350
360
370
[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]RS-4
29+00
29+5
0
30+00
30+50 31+00
31+
5
0
32+00
SECTION-08 START
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
GUARD RAIL, TYP.
SECTION-08 END
Headwall-1
TP-13
UG-4
DG-5
Headwall-2
Tree-14
S08U
S07L
Tree-15
Tree-16
Tree-17
S08L
S09U
Tree-18
RP-27
RP-28
DE-8
RS-3
RS-4
RS-2DE-7
STATION=29+95.00
OFFSET=0.00
NORTHING=465130.19
EASTING=1609343.83
STATION=31+25.00
OFFSET=0.00
NORTHING=465077.58
EASTING=1609225.26
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0003_0013_RHRS_GPS.DWGSLIVNYAK, OLEGSECTION-089/30/2022 4:39 PMLayout:Printed:FIGURE 10
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION8 SITE FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 10 20 30 40
SCALE IN FEET
NOTES
1. ACCURACY FOR GPS POINT AND LINE FEATURES WERE LIMITED
DUE TO POOR SATELLITE CONNECTIVITY RELATED TO
TOPOGRAPHIC AND VEGETATIVE OBSTRUCTIONS ALONG THE
ROADWAY. THUS, GPS FEATURE LOCATIONS ARE APPROXIMATE
AND NOT INTENDED FOR SURVEY OR CONSTRUCTION USE.
2. DUE TO LIMITED ACCURACY FOR GPS LINE FEATURES
CAPTURED IN THE FIELD, GPS LINE FEATURES WERE SIMPLIFIED
TO BE SHOWN AS LINES APPROXIMATELY PARALLEL TO THE
ROADWAY ALIGNMENT CENTERLINE WITH START AND END
POINT TAKEN FROM THE ORIGINAL LINE.
3. SEE TABLES 2, 3, AND 5 IN REPORT FOR ACRONYM DEFINITIONS.
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
GPS POINTS
ADJUSTED GPS POINTS
GPS TRAVERSE LINES
UPSLOPE ROCK SOURCE
CONCRETE[]
MATCHLINE - SEE SHEET 9 MATCHLINE - SEE SHEET 11
150
160
170
180
200
220
230
240
150
160
170
180
200
220
230
240
250
260
270
2
8
0
170
180
200220230
240250260270280
300
310
[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]RS-4
31+00
31+50
32+00
32+50
33+00
33+50
34+0
0
SECTION-09 START
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
GUARD RAIL, TYP.
SECTION-09 END
SET MAG NAIL, TYP.
STATION=32+60.62
OFFSET=6.23R
NORTHING=465075.25
EASTING=1609092.83
Headwall-1
DG-3
TP-14
UG-3
GC-5
DG-4
UG-4
DG-5
S08L
S09U
Tree-18
RP-27
RP-28
DE-9
DE-10
Tree-19
S09L
S10U
Tree-20
RP-30
DE-8
RS-3
RP-29
RS-4
STATION=31+25.00
OFFSET=0.00
NORTHING=465077.58
EASTING=1609225.26
STATION=33+45.00
OFFSET=0.00
NORTHING=465042.70
EASTING=1609014.16
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0003_0013_RHRS_GPS.DWGSLIVNYAK, OLEGSECTION-099/30/2022 4:39 PMLayout:Printed:FIGURE 11
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION9 SITE FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 10 20 30 40
SCALE IN FEET
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
GPS POINTS
ADJUSTED GPS POINTS
GPS TRAVERSE LINES
UPSLOPE ROCK SOURCE
CONCRETE[]
NOTES
1. ACCURACY FOR GPS POINT AND LINE FEATURES WERE LIMITED
DUE TO POOR SATELLITE CONNECTIVITY RELATED TO
TOPOGRAPHIC AND VEGETATIVE OBSTRUCTIONS ALONG THE
ROADWAY. THUS, GPS FEATURE LOCATIONS ARE APPROXIMATE
AND NOT INTENDED FOR SURVEY OR CONSTRUCTION USE.
2. DUE TO LIMITED ACCURACY FOR GPS LINE FEATURES
CAPTURED IN THE FIELD, GPS LINE FEATURES WERE SIMPLIFIED
TO BE SHOWN AS LINES APPROXIMATELY PARALLEL TO THE
ROADWAY ALIGNMENT CENTERLINE WITH START AND END
POINT TAKEN FROM THE ORIGINAL LINE.
3. SEE TABLES 2, 3, AND 5 IN REPORT FOR ACRONYM DEFINITIONS.
MATCHLINE - SEE SHEET 10
MATCHLINE - SEE SHEET 12
50
60
70
90110120
130
150
160
170
180
200
110
120
130
150160170
180
200
220
230
240
[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]33+50
34+00
34+50
35+00
35+50
36+00
36+50SECTION-10 START EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
GUARD RAIL, TYP.
SECTION-10 END
TP-16
TP-15
UG-2
DG-3
UG-3
S09L
S10U
Tree-20
RP-30
RP-32
Tree-21
Tree-22
RP-33
Tree-23
RP-34
Tree-24
S10L
S11U
RP-35
RP-34RP-31
RP-29
STATION=33+45.00
OFFSET=0.00
NORTHING=465042.70
EASTING=1609014.16
STATION=36+35.00
OFFSET=0.00
NORTHING=465019.16
EASTING=1608733.63
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0003_0013_RHRS_GPS.DWGSLIVNYAK, OLEGSECTION-109/30/2022 4:39 PMLayout:Printed:FIGURE 12
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION10 SITE FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 10 20 30 40
SCALE IN FEET
NOTES
1. ACCURACY FOR GPS POINT AND LINE FEATURES WERE LIMITED
DUE TO POOR SATELLITE CONNECTIVITY RELATED TO
TOPOGRAPHIC AND VEGETATIVE OBSTRUCTIONS ALONG THE
ROADWAY. THUS, GPS FEATURE LOCATIONS ARE APPROXIMATE
AND NOT INTENDED FOR SURVEY OR CONSTRUCTION USE.
2. DUE TO LIMITED ACCURACY FOR GPS LINE FEATURES
CAPTURED IN THE FIELD, GPS LINE FEATURES WERE SIMPLIFIED
TO BE SHOWN AS LINES APPROXIMATELY PARALLEL TO THE
ROADWAY ALIGNMENT CENTERLINE WITH START AND END
POINT TAKEN FROM THE ORIGINAL LINE.
3. SEE TABLES 2, 3, AND 5 IN REPORT FOR ACRONYM DEFINITIONS.
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
GPS POINTS
ADJUSTED GPS POINTS
GPS TRAVERSE LINES
UPSLOPE ROCK SOURCE
CONCRETE[]
MATCHLINE - SEE SHEET 11
MATCHLINE - SEE SHEET 13
40
50
60
70
90
110
120
130
150
160
170
50
60
7090 304050
60
70
90
11
0
120
130
[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]36+50
37+
0
0
37+50
38+00
38+50
39+00 39+5
0
SECTION-11 START
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
GUARD RAIL, TYP.
SECTION-11 END
SET MAG NAIL
DG-2
STATION=37+47.86
OFFSET=6.38R
NORTHING=465001.01
EASTING=1608621.73
TP-17
DG-1
GC-6
S10L
S11U
Tree-25
RW-3
RW-4
Tree-27
RP-37
S11L
UG-1
TP-18
TREE 26RP-36
OH-10
RP-35
STATION=36+35.00
OFFSET=0.00
NORTHING=465019.16
EASTING=1608733.63
STATION=39+50.00
OFFSET=0.00
NORTHING=464878.06
EASTING=1608465.87
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0003_0013_RHRS_GPS.DWGSLIVNYAK, OLEGSECTION-119/30/2022 4:39 PMLayout:Printed:FIGURE 13
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION11 SITE FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 10 20 30 40
SCALE IN FEET
NOTES
1. ACCURACY FOR GPS POINT AND LINE FEATURES WERE LIMITED
DUE TO POOR SATELLITE CONNECTIVITY RELATED TO
TOPOGRAPHIC AND VEGETATIVE OBSTRUCTIONS ALONG THE
ROADWAY. THUS, GPS FEATURE LOCATIONS ARE APPROXIMATE
AND NOT INTENDED FOR SURVEY OR CONSTRUCTION USE.
2. DUE TO LIMITED ACCURACY FOR GPS LINE FEATURES
CAPTURED IN THE FIELD, GPS LINE FEATURES WERE SIMPLIFIED
TO BE SHOWN AS LINES APPROXIMATELY PARALLEL TO THE
ROADWAY ALIGNMENT CENTERLINE WITH START AND END
POINT TAKEN FROM THE ORIGINAL LINE.
3. SEE TABLES 2, 3, AND 5 IN REPORT FOR ACRONYM DEFINITIONS.
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
GPS POINTS
ADJUSTED GPS POINTS
GPS TRAVERSE LINES
UPSLOPE ROCK SOURCE
CONCRETE[]
MATCHLINE - SEE SHEET 12
870
880
89
0
900
910
920
860
870
880
890
900
840
850
860
87
0
880
890
900
840850860870870880[][][][][][][][][][][][][][][][][][][][][][][][][][][]
[][][][][][]
[]
[]
[][][][][][][][]SET MAG NAIL
466,416.08 NORTH
1,611,539.08 EAST
ELEV.=881.25
STATION=0+00.00
OFFSET=0.00
NORTHING=466437.15
EASTING=1611567.73
SECTION-01 START
SECTION-01 END
0+
0
0
0+50
1+00
1+50
2
+
0
0
2+50
3+00
3+50
STATION=0+32.23
OFFSET=9.54R
NORTHING=466416.08
EASTING=1611539.08
UTILITY POLE, TYP.
GUARD RAIL, TYP.
EDGE OF ROAD, TYP.
STATION=2+15.00
OFFSET=0.00
NORTHING=466246.78
EASTING=1611509.29
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0014_0024_RHRS-MITIGATION.DWGSLIVNYAK, OLEGSECTION-019/30/2022 4:39 PMLayout:Printed:FIGURE 14
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION1 MITIGATION
FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 10 20 30 40
SCALE IN FEET
[]
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
ROCKFALL FENCE
HAZARDS REMOVAL
CONCRETE
MATCHLINE - SEE SHEET 15
87088089090091092086087088089090084
0850860870880890900840
850
860
870
870
880 7207307407507
6
0770780790800810820830840850860870880890900
770
770
780
780
790
790
800
800
810
810
820
820
830
840
850
860
870
880
890
900
910
[][][][][][][
][][][][][][
][][][][][][][][][][][][]SET MAG NAIL466,416.08 NORTH1,611,539.08 EASTELEV.=881.250+000+501+001+502+002+503+003+
5
0
4+00
4+50
5+00 5+50
6+00 6+507+007+508+008+50SECTION-02 START
SECTION-02 END
GUARD RAIL, TYP.
STATION=2+15.92
OFFSET=0.00
NORTHING=466247.20
EASTING=1611508.47
EDGE OF ROAD, TYP.
STATION=7+35.00
OFFSET=0.00
NORTHING=466426.33
EASTING=1611132.67
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0014_0024_RHRS-MITIGATION.DWGSLIVNYAK, OLEGSECTION-029/30/2022 4:39 PMLayout:Printed:FIGURE 15
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION2 MITIGATION
FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 20 40 60 80
SCALE IN FEET
[]
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
ROCKFALL FENCE
HAZARDS REMOVAL
CONCRETE
MATCHLINE - SEE SHEET 14
MATCHLINE - SEE SHEET 16
600
610
620
630
640
650
660
670
680
690
70
0
71
0
72
0
730
740
750
760
770
780
790
800
810
820
830
840
850
640
650
660
670
680
690
720
730
740
750 760770
78
0
79
0
80
0
810
820
830
6+00
6+
5
0
7+
0
0
7+
5
0
8+
0
0
8+
5
0
9+
0
0
9+5
0
10+
0
0
10+
5
0
11+
0
0
11
+
5
0
12
+
0
0
SECTION-03 END
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
SET MAG NAIL
STATION=11+16.15
OFFSET=7.02R
NORTHING=466233.63
EASTING=1610803.31
STATION=7+35.00
OFFSET=0.00
NORTHING=466426.33
EASTING=1611132.67
SECTION-03 START
STATION=11+50.00
OFFSET=0.00
NORTHING=466209.28
EASTING=1610781.27
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0014_0024_RHRS-MITIGATION.DWGSLIVNYAK, OLEGSECTION-039/30/2022 4:39 PMLayout:Printed:FIGURE 16
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION3 MITIGATION
FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 20 40 60 80
SCALE IN FEET
[]
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
ROCKFALL FENCE
HAZARDS REMOVAL
DRAPED MESH
CONCRETE
MATCHLINE - SEE SHEET 15
MATCHLINE - SEE SHEET 17
370
380
390
400
410
420
430
440
450
460470
480
490
500
510
520
530 540550
560
570
580
590
600
610
620
630
640
650
660
670
680
690
700
710
720
730
740
750
760
400
410
42
0
430
440
450
460
470
480
490
500
510
520
530
540
550
560
570
580
590
600
610
620
630
640
560
570
580
590
600
610
620
630
640
65
0
660
670
680
690
700
710
720
730
740
750
[][][][][][]EEEEEEEEEEEEEEEEEEEEEE11+
0
0
11
+
5
0
12
+
0
0
12+
5
0
13+
0
0
13+
5
0
14+
0
0
14+
5
0
15
+
0
0
15
+
5
0
16
+
0
0
16+
5
0
17+0
0
17+5
0
18+0
0
18+
5
0
19
+
0
0
19
+
5
0
20+
0
0
20+
5
0
21+00
SET MAG NAIL
SECTION-04 START
SECTION-04 END
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
GUARD RAIL, TYP.
HIGH TENSION OVERHEAD WIRE
STATION=11+16.15
OFFSET=7.02R
NORTHING=466233.63
EASTING=1610803.31
STATION=20+84.54
OFFSET=0.30R
NORTHING=465687.31
EASTING=1610011.35
STATION=11+50.00
OFFSET=0.00
NORTHING=466209.28
EASTING=1610781.27
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0014_0024_RHRS-MITIGATION.DWGSLIVNYAK, OLEGSECTION-049/30/2022 4:40 PMLayout:Printed:FIGURE 17
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION4 MITIGATION
FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 30 60 90 120
SCALE IN FEET
[]
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
ROCKFALL FENCE
HAZARDS REMOVAL
DRAPED MESH
CONCRETE
MATCHLINE - SEE SHEET 16
MATCHLINE - SEE SHEET 18
30
0
310
3
3
0
3
4
0
3
5
0
3
6
0
37
0
240
250
260
27
0
28
0
300
31
0
330
34
0
35
0
36
0
3
7
0
3
8
0
390
40
0
410
42
0
430
440
450
46
0
300
310
330
340
350
360
370
380
390
400
410
420
430
440
450
460
470
48
0
49
0
500
51
0
520
5
3
0
36
0
37
0
380
390
400
410
4
2
0
430
440
450
46
0
470
480
490
50
0
510
23
0
24
0
2
5
0
26
0
270
280
300
310
330
340
350
360
370
380
3
9
0
4
0
0
4
1
0
4
2
0
43
0
44
0
4
5
0
4
6
0 4704
8
0
4
9
0
500
5
1
0
520
530
540
[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]EEEEEE1
9
+
5
0
20
+
0
0
20
+
5
0
21+00
21+50
22+
0
0
22
+
5
0
2
3
+
0
0
23+
5
0
24+00
24
+
5
0
25
+
0
0
25+
5
0
2
6
+
0
0
STATION=20+84.05
OFFSET=0.00
NORTHING=465687.56
EASTING=1610011.87
STATION=22+85.56
OFFSET=8.89R
NORTHING=465549.70
EASTING=1609879.38
STATION=24+85.00
OFFSET=0.00
NORTHING=465406.11
EASTING=1609746.10
SECTION-05 END
SECTION-05 START
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
SET MAG NAIL
GUARD RAIL, TYP.\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0014_0024_RHRS-MITIGATION.DWGSLIVNYAK, OLEGSECTION-059/30/2022 4:40 PMLayout:Printed:FIGURE 18
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION5 MITIGATION
FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 20 40 60 80
SCALE IN FEET
[]
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
ROCKFALL FENCE
HAZARDS REMOVAL
DRAPED MESH
CONCRETE
MATCHLINE - SEE SHEET 17
MATCHLINE - SEE SHEET 19
220
230
240
250
260
270
280
300
310
260
270
280
300
310
330
340
350
360
370
380
390
400
410
420
300
310
330
340
350
360
370
380
390
400
410
420
430
440
450
460
[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]25+00
25+50
26+00
26+50
27+00
27+50
SECTION-06 START
SECTION-06 END
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
GUARD RAIL, TYP.
STATION=24+85.00
OFFSET=0.00
NORTHING=465406.11
EASTING=1609746.10
STATION=27+70.00
OFFSET=0.00
NORTHING=465225.90
EASTING=1609535.83
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0014_0024_RHRS-MITIGATION.DWGSLIVNYAK, OLEGSECTION-069/30/2022 4:40 PMLayout:Printed:FIGURE 19
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION6 MITIGATION
FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 10 20 30 40
SCALE IN FEET
[]
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
ROCKFALL FENCE
HAZARDS REMOVAL
DRAPED MESH
CONCRETE
MATCHLINE - SEE SHEET 18
MATCHLINE - SEE SHEET 20
17
0
180
20
0
220
230
24
0
25
0
26
0
270
280
30
0
310
330
34
0
350
360
370
170
180
200
220
230
240
250
260
270
280
300
310
330
340
350
360
370
380
[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]27+50
28+00
28+50
29+00
29
+
5
0
30+00
30+5
0
SECTION-07 START
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
GUARD RAIL, TYP.
SECTION-07 END
STATION=27+70.00
OFFSET=0.00
NORTHING=465225.90
EASTING=1609535.83
STATION=29+95.00
OFFSET=0.00
NORTHING=465130.19
EASTING=1609343.83
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0014_0024_RHRS-MITIGATION.DWGSLIVNYAK, OLEGSECTION-079/30/2022 4:40 PMLayout:Printed:FIGURE 20
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION7 MITIGATION
FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 10 20 30 40
SCALE IN FEET
[]
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
ROCKFALL FENCE
HAZARDS REMOVAL
DRAPED MESH
CONCRETE
MATCHLINE - SEE SHEET 19
MATCHLINE - SEE SHEET 21
170
180
200220
230
240
250
260
270
280
300
310
170
180
200
220
230
240
250
260
270
280
300
310
330
340
350
360
370
[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]29+00
29+5
0
30+00
30+50 31+00
31+
5
0
32+00
SECTION-08 START
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
GUARD RAIL, TYP.
SECTION-08 END
STATION=29+95.00
OFFSET=0.00
NORTHING=465130.19
EASTING=1609343.83
STATION=31+25.00
OFFSET=0.00
NORTHING=465077.58
EASTING=1609225.26
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0014_0024_RHRS-MITIGATION.DWGSLIVNYAK, OLEGSECTION-089/30/2022 4:40 PMLayout:Printed:FIGURE 21
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION8 MITIGATION
FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 10 20 30 40
SCALE IN FEET
[]
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
ROCKFALL FENCE
HAZARDS REMOVAL
DRAPED MESH
CONCRETE
MATCHLINE - SEE SHEET 20
MATCHLINE - SEE SHEET 22
150
160
170
180
200
220
230
240
150
160
170
180
200
220
230
240
250
260
270
2
8
0
170
180
200220230
240250260270280
300
310
[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]31+00
31+50
32+00
32+50
33+00
33+50
34+0
0
SECTION-09 START
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
GUARD RAIL, TYP.
SECTION-09 END
SET MAG NAIL, TYP.
STATION=32+60.62
OFFSET=6.23R
NORTHING=465075.25
EASTING=1609092.83
STATION=31+25.00
OFFSET=0.00
NORTHING=465077.58
EASTING=1609225.26
STATION=33+45.00
OFFSET=0.00
NORTHING=465042.70
EASTING=1609014.16
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0014_0024_RHRS-MITIGATION.DWGSLIVNYAK, OLEGSECTION-099/30/2022 4:40 PMLayout:Printed:FIGURE 22
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION9 MITIGATION
FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 10 20 30 40
SCALE IN FEET
[]
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
ROCKFALL FENCE
HAZARDS REMOVAL
DRAPED MESH
CONCRETE
MATCHLINE - SEE SHEET 21
MATCHLINE - SEE SHEET 23
50
60
70
90110120
130
150
160
170
180
200
110
120
130
150160170
180
200
220
230
240
[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]33+50
34+00
34+50
35+00
35+50
36+00
36+50SECTION-10 START EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
GUARD RAIL, TYP.
SECTION-10 END
STATION=33+45.00
OFFSET=0.00
NORTHING=465042.70
EASTING=1609014.16
STATION=36+35.00
OFFSET=0.00
NORTHING=465019.16
EASTING=1608733.63
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0014_0024_RHRS-MITIGATION.DWGSLIVNYAK, OLEGSECTION-109/30/2022 4:40 PMLayout:Printed:FIGURE 23
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION10 MITIGATION
FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 10 20 30 40
SCALE IN FEET
[]
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
ROCKFALL FENCE
HAZARDS REMOVAL
DRAPED MESH
CONCRETE
MATCHLINE - SEE SHEET 22
MATCHLINE - SEE SHEET 24
40
50
60
70
90
110
120
130
150
160
170
50
60
7090 304050
60
70
90
11
0
120
130
[][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][][]36+50
37+
0
0
37+50
38+00
38+50
39+00 39+5
0
SECTION-11 START
EDGE OF ROAD, TYP.
UTILITY POLE, TYP.
GUARD RAIL, TYP.
SECTION-11 END
SET MAG NAIL
STATION=37+47.86
OFFSET=6.38R
NORTHING=465001.01
EASTING=1608621.73
STATION=36+35.00
OFFSET=0.00
NORTHING=465019.16
EASTING=1608733.63
STATION=39+50.00
OFFSET=0.00
NORTHING=464878.06
EASTING=1608465.87
\\HALEYALDRICH.COM\SHARE\PDX_DATA\NOTEBOOKS\0203303-001_WAIPIO_VALLEY_GEOTECHNICAL_DESIGN\CAD\FIGURES\WAIPIO VALLEY ROAD GEOTECH DESIGN\0203303_001_0014_0024_RHRS-MITIGATION.DWGSLIVNYAK, OLEGSECTION-119/30/2022 4:40 PMLayout:Printed:FIGURE 24
WAIPI‘O VALLEY ROAD GEOTECHNICAL DESIGN
WAIPI‘O VALLEY ROAD
HONOKA‘A, HAWAI‘I
SECTION11 MITIGATION
FEATURES
SCALE: AS SHOWN
SEPTEMBER 2022
0 10 20 30 40
SCALE IN FEET
[]
LEGEND
SET MAG NAIL
UTILITY POLE
ROAD SIGN
EDGE OF ROAD
GUARD RAIL
SECTION ALIGNMENT
2' TOPOGRAPHIC CONTOUR
10' TOPOGRAPHIC CONTOUR
ROCKFALL FENCE
HAZARDS REMOVAL
DRAPED MESH
CONCRETE
MATCHLINE - SEE SHEET 23
APPENDIX A
Photo Log
Waipio Valley Road Evaluation Project
File No. 0203303
Date : May 16
Haley & Aldrich Inc. Page 1 of 9
Photo 1: A corestone, CS-01.
Photo 2: Differential erosion, DE-02.
Waipio Valley Road Evaluation Project
File No. 0203303
Date : May 16
Haley & Aldrich Inc. Page 2 of 9
Photo 3: Overhang, OH-01.
Photo 4: Rock package, RP-36.
Waipio Valley Road Evaluation Project
File No. 0203303
Date : May 16
Haley & Aldrich Inc. Page 3 of 9
Photo 5: Root wedging, RW-01.
Waipio Valley Road Evaluation Project
File No. 0203303
Date : May 16
Haley & Aldrich Inc. Page 4 of 9
Photo 6: Scallop, SC-02.
Waipio Valley Road Evaluation Project
File No. 0203303
Date : May 16
Haley & Aldrich Inc. Page 5 of 9
Photo 7: Tree, Tree-02.
Photo 8: Upslope gully, UG-05.
Waipio Valley Road Evaluation Project
File No. 0203303
Date : May 16
Haley & Aldrich Inc. Page 6 of 9
Photo 9: Upslope rock source, RS-04.
Photo 10: Downslope gully, DG-10.
Waipio Valley Road Evaluation Project
File No. 0203303
Date : May 16
Haley & Aldrich Inc. Page 7 of 9
Photo 11: Boulder, Boulder-01.
Photo 12: Culvert, Culvert-01.
Waipio Valley Road Evaluation Project
File No. 0203303
Date : May 16
Haley & Aldrich Inc. Page 8 of 9
Photo 13: Headwall, Headwall-03.
Photo 14: Telephone pole, TP-08.
Waipio Valley Road Evaluation Project
File No. 0203303
Date : May 16
Haley & Aldrich Inc. Page 9 of 9
Photo 15: Swale, SW-03.
APPENDIX B
GPS Field Data
Field ID Photo Video #Shape Section Feature Name Feature Full Name
1 Point 11 TP 18 Telephone Pole 18
2 Point 11 DG 01 Downslope Gully 1
3 Point 11 TP 17 Telephone Pole 17
4 Point 11 DG 02 Downslope Gully 2
5 Point 11 GC 06 Ground Control 6
6 Point 10 TP 16 Telephone Pole 16
7 Point 10 TP 15 Telephone Pole 15
8 Point 10 UG 02 Upslope Gully 2
9 Point 10 DG 03 Downslope Gully 3
10 Point 9 TP 14 Telephone Pole 14
11 Point 10 UG 03 Upslope Gully 3
12 Point 9 GC 05 Ground Control 5
13 Point 9 DG 04 Downslope Gully 4
14 Point 9 Headwall 01 Headwall 1
15 Point 8 TP 13 Telephone Pole 13
16 Point 8 UG 04 Upslope Gully 4
17 Point 8 DG 05 Downslope Gully 5
18 Point 7 TP 12 Telephone Pole 12
19 Point 7 Headwall 02 Headwall 2
20 Point 6 TP 11 Telephone Pole 11
21 Point 6 DG 07 Downslope Gully 7
22 Point 6 UG 06 Upslope Gully 6
23 Point 6 DG 06 Downslope Gully 6
24 Point 6 UG 05 Upslope Gully 5
25 Point 6 Headwall 03 Headwall 3
26 Point 5 TP 10 Telephone Pole 10
27 Point 5 GC 04 Ground Control 4
28 Point 5 DG 08 Downslope Gully 8
29 Point 5 UG 07 Upslope Gully 7
30 Line Waipio Valley Road Waipio Valley Road
31 Point 4 TP 09 Telephone Pole 9
32 1465 Point 4 SW 01 Swale 1
33 1466 Point 4 SW 02 Swale 2
34 1467 Point 4 SW 03 Swale 3
35 1468 Point 4 SW 04 Swale 4
36 Point 4 TP 08 Telephone Pole 8
37 1469 Point 4 SW 05 Swale 5
38 Point 4 GC 03 Ground Control 3
39 1474 1475 Point 4 SW 06 Swale 6
40 Point 4 TP 07 Telephone Pole 7
41 Point 4 DG 09 Downslope Gully 9
42 1467 Point 4 SW 07 Swale 7
43 Point GC 00 Ground Control 0
44 Point 4 TP 06 Telephone Pole 6
45 1477 Point 4 SW 08 Swale 8
46 Point 3 TP 05 Telephone Pole 5
47 Point 3 Boulder Boulder
48 Point 3 GC 02 Ground Control 2
49 1478 1480 Point 3 SW 09 Swale 9
50 Point 3 TP 04 Telephone Pole 4
51 1481 1482 Point 3 SW 10 Swale 10
52 Point 2 TP 03 Telephone Pole 3
53 1483 Point 2 SW 11 Swale 11
54 1484 Point 2 SW 12 Swale 12
55 Point 2 TP 02 Telephone Pole 2
56 1485 1486 Point 2 SW 13 Swale 13
57 Point 2 DG 10 Downslope Gully 10
58 Point 2 DG 11 Downslope Gully 11
59 Point 2 DG 12 Downslope Gully 12
60 1489 1490 Point 2 SW 14 Swale 14
61 Point 1 TP 01 Telephone Pole 1
62 Point 1 GC 01 Ground Control 1
63 1491 Point 1 SW 15 Swale 15
64 Point 1 Culvert Outlet Culvert Outlet
65 Point 1 Culvert Inlet Culvert Inlet
66 Point 1 S01U Section 1 Upper
67 Point 1 S01L Section 1 Lower
68 1514 1515 Point 2 S02U Section 2 Upper
69 Point 2 S02L Section 2 Lower
70 1553 Point 2 CS 01 Corestone 1
71 1554 1557 Line 2 OH 01 Overhang 1
72 1558 Point 2 SC 01 Scallop 1
73 1559 Point 2 CS 02 Corestone 2
74 1561 1564 Line 2 SC 02 Scallop 2
75 1565 1567 Line 2 SC 03 Scallop 3
76 1560 Point 2 CS 03 Corestone 3
77 1568 Point 2 SC 04 Scallop 4
78 1568 Point 2 CS 04 Corestone 4
79 1568 Line 2 SC 04 Line Scallop 4
80 1570 Line 2 SC 05 Scallop 5
81 1571 1572 Point 2 Tree 01 Tree 1
82 1573 1576 Line 2 OH 02 Overhang 2
83 1577 Point 2 Tree 02 Tree 2
84 1577 Point 2 Tree 03 Tree 3
85 Point 3 S03U Section 3 Upper
86 1578 1586 Line 3 OH 03 Overhang 3
87 1587 Point 3 SC 06 Scallop 6
88 1588 Line 3 RP 01 Rock Package 1
89 1589 Point 3 Tree 04 Tree 4
90 1590 Point 3 Tree 05 Tree 5
91 1591 Point 3 Tree 06 Tree 6
92 1592 Point 3 RP 02 Rock Package 2
93 1593 1594 Line 3 OH 04 Overhang 4
94 1595 1596 Line 3 OH 05 Overhang 5
95 Point 3 S03L Section 3 Lower
96 Point 4 S04U Section 4 Upper
97 1597 Point 4 RP 03 Rock Package 3
98 1598 Line 4 OH 06 Overhang 6
99 1599 1601 Line 4 RP 04 Rock Package 4
100 1602 Line 4 OH 07 Overhang 7
101 1603 Point 4 Tree 07 Tree 7
102 1604 Point 4 RP 05 Rock Package 5
103 1605 Point 4 RP 06 Rock Package 6
104 1606 Point 4 RP 07 Rock Package 7
105 1607 1608 Point 4 RP 08 Rock Package 8
106 1609 1610 Point 4 RP 09 Rock Package 9
107 1611 1613 Line 4 RP 10 Rock Package 10
108 1614 1616 Line 4 RP 11 Rock Package 11
109 1617 1618 Line 4 OH 08 Overhang 8
110 1619 1626 Line 4 RP 12 Rock Package 12
111 1627 Point 4 Tree 08 Tree 8
112 1628 Point 4 RP 13 Rock Package 13
113 1629 Point 4 Tree 09 Tree 9
114 1630 Point 4 RP 14 Rock Package 14
115 1631 Point 4 RP 15 Rock Package 15
116 1632 Point 4 Tree 10 Tree 10
117 Point 4 S04L Section 4 Lower
118 Point 5 S05U Section 5 Upper
119 1633 Point 5 RP 16 Rock Package 16
120 1634 Point 5 DE 01 Differential Erosion 1
121 1635 Line 5 OH 09 Overhang 9
122 1636 Point 5 Tree 11 Tree 11
123 1637 Point 5 Tree 12 Tree 12
124 1638 1639 Point 5 RP 17 Rock Package 17
125 1640 1641 Line 5 RP 18 Rock Package 18
126 1642 1644 Line 5 RP 19 Rock Package 19
127 1645 Point 5 RP 20 Rock Package 20
128 1646 Line 5 DE 02 Differential Erosion 2
129 Point 5 S05L Section 5 Lower
130 Point 6 S06U Section 6 Upper
131 1647 Point 6 DE 03 Differential Erosion 3
132 1648 Point 6 RP 21 Rock Package 21
133 1649 Point 6 Tree 13 Tree 13
134 1650 Point 6 RW 01 Root Wedging 1
135 1651 Point 6 DE 04 Differential Erosion 4
136 1652 Point 6 RW 02 Root Wedging 2
137 1653 Point 6 DE 05 Differential Erosion 5
138 1654 Point 6 RP 22 Rock Package 22
139 1655 1657 Line 6 RP 23 Rock Package 23
140 1658 Point 6 DE 06 Differential Erosion 6
141 1659 Line 6 RS 01 Upslope Rock Source 1
142 Point 6 S06L Section 6 Lower
143 Point 7 S07U Section 7 Upper
144 1660 Point 7 RP 24 Rock Package 24
145 1661 Point 7 RP 25 Rock Package 25
146 1662 Point 7 RP 26 Rock Package 26
147 Point 7 S07L Section 7 Lower
148 Point 8 S08U Section 8 Upper
149 1663 Point 8 Tree 14 Tree 14
150 1664 1665 Line 8 DE 07 Differential Erosion 7
151 1666 Point 8 Tree 15 Tree 15
152 1667 Point 8 Tree 16 Tree 16
153 1668 Line 8 RS 02 Upslope Rock Source 2
154 1669 Point 8 Tree 17 Tree 17
155 Point 8 S08L Section 8 Lower
156 Point 9 S09U Section 9 Upper
157 1672 Point 9 Tree 18 Tree 18
158 1673 Point 9 RP 27 Rock Package 27
159 1675 Point 9 RP 28 Rock Package 28
160 1676 Line 9 RS 04 Upslope Rock Source 4
161 1677 Point 9 DE 09 Differential Erosion 9
162 1678 Point 9 DE 10 Differential Erosion 10
163 1679 Point 9 Tree 19 Tree 19
164 Point 9 S09L Section 9 Lower
165 Point 10 S10U Section 10 Upper
166 1680 Point 10 Tree 20 Tree 20
167 1681 1682 Line 10 RP 29 Rock Package 29
168 1683 Point 10 RP 30 Rock Package 30
169 1684 Line 10 RP 31 Rock Package 31
170 1686 Point 10 RP 32 Rock Package 32
171 1687 Point 10 Tree 21 Tree 21
172 1688 Point 10 Tree 22 Tree 22
173 1689 Point 10 RP 33 Rock Package 33
174 1690 Point 10 Tree 23 Tree 23
175 1691 1692 Point 10 RP 34 Rock Package 34
176 1691 1692 Line 10 RP 34 Rock Package 34
177 1693 Point 10 Tree 24 Tree 24
178 Point 10 S10L Section 10 Lower
179 Point 11 S11U Section 11 Upper
180 1694 1695 Line 11 RP 35 Rock Package 35
181 1696 Point 11 Tree 25 Tree 25
182 1697 1698 Point 11 RW 03 Root Wedging 3
183 1699 Point 11 RW 04 Root Wedging 4
184 1700 Line 11 RP 36 Rock Package 36
185 1701 Line 11 Tree 26 Tree 26
186 1702 Point 11 Tree 27 Tree 27
187 1703 Point 11 RP 37 Rock Package 37
188 1704 Line 11 OH 10 Overhang 10
189 Point 11 S11L Section 11 Lower
190 Point 12 S12L Section 12 Lower
191 Line 12 S12 Line Section 12 Line
192 Point 12 TP 25 Telephone Pole 25
193 Point 12 TP 24 Telephone Pole 24
194 Point 12 TP 23 Telephone Pole 23
195 Point 12 TP 22 Telephone Pole 22
196 Point 12 TP 21 Telephone Pole 21
197 Point 12 TP 20 Telephone Pole 20
198 Point 12 TP 19 Telephone Pole 19
199 Point 11 UG 01 Upslope Gully 1
200 1671 Point 8 DE 08 Differential Erosion 8
201 1670 Point 8 RS 03 Upslope Rock Source 3
APPENDIX C
Features Data by Section
Corestone Differential
Erosion
Downslope
Gully Overhang Rock
Package
Root
Wedging Scallop Tree Upslope
Gully
Upslope
Rock
Source
1 0+00 2+15 215 1 See note
below.
Culvert-Inlet/Outlet, SW-15, TP-
01, GC-01
2 2+15 7+35 520
CS-01,
CS-02,
CS-03,
CS-04
DG-10,
DG-11,
DG-12
OH-01,
OH-02
SC-01,
SC-02,
SC-03,
SC-04,
SC-05
Tree-01,
Tree-02,
Tree-03 17
SW-14, SW-13, SW-12, SW-11,
TP-02, TP-03
3 7+35 11+50 415
OH-03,
OH-04,
OH-05
RP-01,
RP-02
SC-06 Tree-04,
Tree-05,
Tree-06 9
Boulder, SW-10, SW-09,
TP-04, TP-05, GC-02
4 11+50 20+85 935
DG-09 OH-06,
OH-07,
OH-08
RP-03,
RP-04,
RP-05,
RP-06,
RP-07,
RP-08,
RP-09,
RP-10,
RP-11,
RP-12,
RP-13,
RP-14,
RP-15
Tree-07,
Tree-08,
Tree-09,
Tree-10
21
SW-08, SW-07, SW-06, SW-05,
SW-04, SW-03, SW-02, SW-01,
TP-06, TP-07, TP-08, TP-09,
GC-03
5 20+85 24+85 400
DE-01,
DE-02
DG-08 OH-09 RP-16,
RP-17,
RP-18,
RP-19,
RP-20
Tree-11,
Tree-12
UG-07
12
TP-10, GC-04
6 24+85 27+70 285
DE-02,
DE-03,
DE-04,
DE-05,
DE-06
DG-06,
DG-07
RP-21,
RP-22,
RP-23
RW-01,
RW-02
Tree-13 UG-06,
UG-05
RS-01
16
Headwall-03, TP-11
7 27+70 29+95 225
RP-24,
RP-25,
RP-26
Tree-14
4
Headwall-02, TP-12
8 29+95 31+25 130
DE-07,
DE-08
Tree-15,
Tree-16,
Tree-17
UG-04 RS-02,
RS-03 8
TP-13
9 31+25 33+45 220
DE-09,
DE-10
DG-04,
DG-05
RP-27,
RP-28
Tree-18 RS-04
8
Headwall-01, TP-14, GC-05
10 33+45 36+35 290
DG-03 RP-29,
RP-30,
RP-31,
RP-32,
RP-33,
RP-34,
Tree-19,
Tree-20,
Tree-21,
Tree-22,
Tree-23,
Tree-24
UG-03,
UG-02
15
TP-15, TP-16
11 36+35 39+50 315
DG-01,
DG-02
OH-10 RP-35,
RP-36,
RP-37
RW-03,
RW-04
Tree-25,
Tree-26,
Tree-27
UG-01
12
TP-17, TP-18, GC-6
Total
Hazard
Features
Other
Features
1 While no hazards were mapped within Section-01, there is a noted sloughing of soil along the embankment between Sta. 0+00 and Sta. 2+15. The heavy vegetation obscures much of the failing scarp but evidence of outwash and
small cobbles is present along the side of the road.
Section Start
Station
End
Station
Length
(ft)
Hazard Feature Types
APPENDIX D
Rockfall Mitigation Measures and Estimated Costs by
Section
Table 1. Rockfall Mitigation Measures and Estimated Costs by Section
Section Mitigation Units Unit Costs per sq ft* Subtotal Costs Section Total Cost
1 Hazards Removal 2,500 ft2 $2 – $5 $5,000 – $13,000 $5,000 – $13,000
2 Hazards Removal 13,500 ft2 $2 – $5 $27,000 – $68,000 $27,000 – $68,000
3 Rock Scaling 6,000 ft2 $6 – $13 $36,000 – $78,000 $84,000 – $198,000 Drapery Netting 6,000 ft2 $8 – $20 $48,000 – $120,000
4 Rock Scaling 16,500 ft2 $6 – $13 $99,000 – $215,000 $231,000 – $545,000 Drapery Netting 16,500 ft2 $8 – $20 $132,000 –$330,000
5 Rock Scaling 4,000 ft2 $6 – $13 $24,000 – $52,000 $56,000 – $132,000 Drapery Netting 4,000 ft2 $8 – $20 $32,000 – $80,000
6
Rock Scaling 1,500 ft2 $6 – $13 $9,000 – $20,000
$101,000 – $500,000 Drapery Netting 1,500 ft2 $8 – $20 $12,000 – $30,000
Rockfall Impact
Fence 100 ft $800 – $4,500
per linear foot $80,000 – $450,000
7 Rock Scaling 1,500 ft2 $6 – $13 $9,000 – $20,000 $21,000– $50,000 Drapery Netting 1,500 ft2 $8 – $20 $12,000 – $30,000
8
Rock Scaling 1,000 ft2 $6 – $13 $6,000 – $13,000
$94,000 –$483,000 Drapery Netting 1,000 ft2 $8 – $20 $8,000 – $20,000
Rockfall Impact
Fence 100 ft $800 – $4,500
per linear foot $80,000 – $450,000
9
Rock Scaling 2,000 ft2 $6 – $13 $12,000 –$26,000
$108,000 – $516,000 Drapery Netting 2,000 ft2 $8 – $20 $16,000 – $40,000
Rockfall Impact
Fence 100 ft $800 – $4,500
per linear foot $80,000 – $450,000
10 Rock Scaling 3,000 ft2 $6 – $13 $18,000 – $39,000 $42,000 – $99,000 Drapery Netting 3,000 ft2 $8 – $20 $24,000 – $60,000
11 Rock Scaling 3,000 ft2 $6 – $13 $18,000 – $39,000 $42,000 – $99,000 Drapery Netting 3,000 ft2 $8 – $20 $24,000 – $60,000
Notes:
* Unit costs are provided per square foot except where noted.
1 Phases 2 and 3 will require clearing and grubbing, which are included in the estimates for the installation of the noted systems. 2 The above mitigation cost estimates are approximate and should not be considered “Engineer Estimates”, but rough
order of magnitude costs suitable for conceptual planning purposes only and do not account for ancillary permitting or
construction costs related to the construction of these given measure.
3 Further evaluation may be required to confirm the needs for mitigation and for design of mitigation measures.