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LWD management has evolved over the years from removal of debris to a long term passing management approach. A LWD passing approach would cause large wooden logs and branches to rotate parallel with the flow of the creek to pass beneath bridges.
The average tree length in the Soquel Creek watershed was identified as being between 15 and 30 feet long. The narrowest clear span of the Stockton Avenue Bridge is 10 feet. This appears to cause buildup of debris that can span the whole creek width, cause damage to the bridge, and cause significant flooding to adjacent areas.
The 2016 Due Diligence memorandum, prepared
by Kimley Horn, identified four potential debris
control countermeasures: debris sweeper, debris
fins, debris deflectors (cage and pier variants)
and bridge replacement. The purpose of this
report is to analyze each debris diversion
countermeasure and potential flood risk along
Soquel Creek.
Existing Conditions
The Stockton Avenue Bridge is furthest downstream bridge in the Soquel Creek watershed, which is known to have LWD that has historically caused flooding by damming up bridges, specifically in 1955 and 1982 storm seasons. Bridges upstream from the site, at Soquel Drive and Highway 1, have larger spans than the Stockton Avenue Bridge. The span of the Soquel Drive Bridge, which was replaced in 1890, 1927, 1956 and most recently in 2003 with the added intent to facilitate the passage of LWD, now has a span of 140 feet compared to the Stockton Avenue Bridge center clear span of 80 feet.
This increase in bridge clear span at Soquel Drive Bridge creates a higher potential than historically existed for debris to accumulate upstream of Stockton Avenue Bridge and cause flooding risk to low laying areas. During a March 18th, 2024 site visit, LWD was observed in the eastern bridge span. Sediment accumulated around the LWD reducing the hydraulic capacity of the bridge.
Figure: Debris Accumulation in
Eastern Span of Stockton
Avenue Bridge
Figure: 1982 Debris Accumulation upstream of
Soquel Drive Bridge.
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Countermeasure Alternatives
Alternative 1: Debris Diversion Fin
Debris diversion fins are comprised of
vertical, free-standing, reinforced
concrete walls extending upstream from,
but not connected to, the existing bridge
piers. The top of the fin wall can be
sloping or horizontal. In the proposed
alternative, the top of the fin wall is
sloping; higher adjacent to the bridge
and declining into the fin wall footing at
the opposite end. The eastern fin wall is
suggested to be installed at an angle to
minimize debris catch between the
bridge pier and the creek wall; a space that
is approximately 8 feet to 9 feet wide at
the narrowest.
Alternative 2: Debris Diversion Cage
Debris diversion cages are meant to
orient large debris to flow under the
bridge. The debris diversion cages are
comprised of a prefabricated steel
triangular cage upstream of a bridge
that are designed to orient debris such
as trees or logs so that they pass under
the bridge longitudinally. The cage may
also be located directly in front of a pier.
For bridge deflectors to work, the flow
direction needs to be fairly stable.
Installation of a debris diversion cages at
the Stockton Avenue Bridge would be
comprised of cages at each bridge pier, placed on three reinforced concrete piers within the Soquel Creek channel.
Figure: Debris Diversion Fin
Figure: Debris Diversion Cage
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Alternative 3: Debris Deflector Piers
Debris diversion piers are meant to orient
large debris to flow under the bridge. The
debris deflectors are comprised of vertical
poles upstream of a bridge that are
designed to orient debris such as trees or
logs so that it passes under the bridge
longitudinally. The deflectors may also be
located directly in front of a pier. For
bridge deflectors to work, the flow
direction needs to be fairly stable. The
design of this type of system is
complicated, and physical model tests
may be necessary.
Implementation of a debris diversion piers at the Stockton Avenue Bridge would be comprised of eleven (11) piers at each bridge pier, placed on reinforced concrete piers with in the Soquel Creek channel.
Alternative 4: Debris Sweeper
Debris sweepers are a vaned cylinder
located in front of a pier that rotates with
the flow and “sweeps” the debris away
from the pier and into the flow between
bridge piers. Sweepers are usually
polyethylene and float up and down so
they can move with the water surface.
Implementation at the Stockton Avenue
Bridge would include the installation of two
manufactured floating debris sweepers
adjacent to the existing piers within the
channel of Soquel Creek. The sweepers
would be installed on reinforced concrete
piers, and the sweepers would rise and fall
with the water level of the creek.
Figure: Debris Diversion Piers
Figure: Debris Sweeper
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Alternative 5: Bridge Replacement
Replacement of the Stockton Avenue Bridge would include a 135 foot clear span bridge, with abutments in the same location as the existing bridge and a six (6) foot deck structure. The replacement would widen the bridge by eight (8) feet to 52 feet wide. The widened bridge will accommodate the increased street section.
Figure: Preliminary Longitudinal Section of Bridge Replacement 281
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Hydraulic Analysis
Water surface elevations within Soquel Creek at the Stockton Avenue Bridge were calculated using HEC-RAS version 6.5, the Army Corps of Engineer’s Hydrologic Engineering Center’s River Analysis System computer program. Use of HEC-RAS to model channel hydraulics for the scenarios provided is considered appropriate as the water in the channel, at the elevations modeled, is flowing in one direction, downstream, toward the ocean during the flow event.
Topography
The source for topographic information in the area of the project is the County of Santa Cruz Geographic Information Systems Department.
Bridge
The source for dimensions of the Stockton Avenue Bridge is the As Built Plans Set from Caltrans, Document No. 40008995 for Capitola Bridge, dated October 1933.
Peak Flow
The peak flow used for the 100-year storm event is 17,500 cfs in accordance with the Federal Emergency Management Agency’s (FEMA) Flood Insurance Study (FIS) for Santa Cruz County, CA and Incorporated Areas, FIS No. 06087CV001C.
The peak flow for the lower flow event of 1,200 cfs is pulled from the United States Geological Survey’s (USGS) website, “USGS Water Data for the Nation” (waterdata.usgs.gov/nwis). USGS provides data retrieved from a flow monitoring location in Soquel Creek. Between January 2024 and March 2024 four storms produced flows of 1000 cfs or more in Soquel Creek. Large woody debris was observed to be caught below the Stockton Avenue Bridge in February 2024 and in March 2024.
Hydrograph for Unsteady Flow Analysis
A simplified hydrograph was developed based upon the flow data for the lower peak flow storm of January 2024. The hydrograph assumes a storm flow duration of 24 hours with peak flow occurring at 9 hours and 15 minutes after the start of the flow event.
Starting Hydraulic Grade Line
In this preliminary analysis, to evaluate the response of hydraulic grade line upstream of the Stockton Avenue Bridge to each of the Countermeasure Alternatives, it is assumed that the tide is low and Soquel Creek flows freely at normal depth conditions toward the Pacific Ocean.
Channel Roughness
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United States Geological Survey Water-Supply Paper 2339 “Guide for Selecting Manning’s Roughness Coefficients for Natural Channels and Flood Plains” G. Arcement, Jr. & V. Schneider Main Channel:
Table 1. “Base values of Manning’s n”
Sand Channel
n = 0.026
Floodplains:
Utilize a base value of 0.026 and add an adjustment factor from:
Table 2. “Adjustment values for factors that affect the roughness of a channel” Amount of vegetation – medium – adjustment factor 0.010 n = 0.036
Debris Piers
HEC-RAS includes the ability to identify the width and depth of floating debris caught on bridge piers, which affect the channel cross section geometry. Data is not available for the amount of LWD that could be caught on a structure for any given storm event. Assumptions were made for the amount of floating debris caught on the Stockton Avenue Bridge and the counter measure alternatives. These assumptions are provided below.
Additional Assumptions for Existing Condition and Countermeasure Alternatives Existing Condition
• Assumes that debris is caught on the bridge piers.
• Debris capture is represented by debris piers in the HEC-RAS model • Debris piers extend 15 feet on either side of the centerline of the eastern bridge pier. • Debris piers extend 10 feet on either side of the centerline of the western bridge pier. • The debris pier floats below the water surface at 6’ deep.
Alternative 1: Debris Diversion Fin
• Fins are represented by a blockage in the channel.
• Because the fin is angled toward the creek wall, it is assumed that LWD for the most part, continues to flow past and under the bridge to the ocean. However, it is assumed that some amount of debris will be caught on “v” that the fin forms with the creek wall. The 283
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LWD retained on the angled fin is assumed to block the flow of water from passing under the small eastern span of the bridge.
Goal of analysis: See whether there is a reduction in capacity of the channel and resulting increase in water surface elevation, assuming that the fins are mostly functioning but some debris is caught on them.
Alternative 2: Debris Diversion Cage
• Both cages are represented as the piers of a false bridge inserted upstream of the Stockton Avenue Bridge
• The center of the false bridge is at the midpoint of the triangle made by the cage. • The diversion cages are represented as piers of the false bridge. It is assumed that some amount of debris will be caught on the cages, rendering the space inside the cage an area of ineffective flow.
• The width of the false bridge is the same as the length of the triangle made by the cage in the stream.
• The piers of the false bridge vary in width from upstream to downstream. Pier widths up and downstream match the width of the cage in the stream. • The floating pier debris option is turned on to account for some amount of debris caught on the debris diversion cage.
• The width of the debris is assumed to extend 4.75 feet on either side of the nose of the cage.
• The depth of debris is assumed to extend 9.5 feet below the water surface.
Goal of analysis: See the reduction in capacity of the channel and resulting increase in water surface elevation assuming that the diversion cages are mostly functioning but some debris is caught on them.
Alternative 3: Debris Deflector Piers
• Both sets of piers are represented as the piers of a false bridge inserted upstream of the Stockton Avenue Bridge
• The center of the false bridge is at the midpoint of the pier triangle. • It is assumed that some amount of debris will be caught on the piers, rendering the space inside the pier configuration, behind the debris, an area of ineffective flow. • The width of the false bridge is the same as the length of the triangle in the stream. • The piers of the false bridge vary in width from upstream to downstream. Pier widths up and downstream match the width of the debris piers in the stream. • The floating pier debris option is turned on to account for some amount of debris caught on the piers.
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• The width of the debris is assumed to extend 4.75 feet on either side of the pier. • The depth of debris is assumed to be 4 feet below the water surface.
Goal of analysis: See the whether there is a reduction in capacity of the channel and resulting increase in water surface elevation assuming that the deflector piers are mostly functioning but some debris is caught on them. The amount of debris is less than for the Debris Diversion Cages.
Alternative 4: Debris Sweeper
• Both sweepers are represented as the piers of a false bridge inserted upstream of the Stockton Avenue Bridge
• The center of the false bridge is at the centerline of the sweeper and its supporting pole. • It is assumed that some amount of debris will be caught on the sweeper. • The floating pier debris option is turned on to account for some amount of debris caught on the sweeper.
• The width of the debris is assumed to extend 2.75 feet on either side of the sweeper. • The depth of debris is assumed to be 4 feet below the water surface.
Goal of the analysis: See the whether there is a reduction in capacity of the channel and resulting increase in water surface elevation assuming that the debris sweepers are mostly functioning but some debris is caught on them.
Alternative 5: Bridge Replacement
Goal of the analysis: See the change in capacity of the channel, over existing conditions, with the construction of a clear span bridge and removal of existing bridge and bridge piers in the channel.
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Results
Table 1: Depth at Upstream Side of Stockton Avenue Bridge All Alternatives with Debris Capture
Model
Station
170.36
Existing
Conditions
(with debris)
(feet)
Alternative 1
Debris Fin
(feet)
Alternative 2
Debris Cage
(feet)
Alternative 3
Debris Piers
(feet)
Alternative 4
Debris
Sweeper
(feet)
Q100
17,500 cfs 11.29 12.82 11.72 11.72 11.66
QJan2024
1,200 cfs 3.96 5.50 4.02 4.02 4.01
Table 2: Depth 50 feet upstream of Stockton Avenue Bridge All Alternatives with Debris Capture
Model
Station
218.85
Existing
Conditions
(with debris)
(feet)
Alternative 1
Debris Fin
(feet)
Alternative 2
Debris Cage
(feet)
Alternative 3
Debris Piers
(feet)
Alternative 4
Debris
Sweeper
(feet)
Q100
17,500 cfs 15.61 18.11 14.20 13.90 14.17
QJan2024
1,200 cfs 4.18 6.53 4.18 4.17 4.18
Table 3: Depth at Upstream Side of Stockton Avenue Bridge Existing Conditions and Alternative 5 (Clear Span Bridge) Model
Station
170.36
Existing
Conditions
(feet)
Alternative 5
Clear Span
Bridge
(feet)
Q100
17,500 cfs 11.71 11.91
QJan2024
1,200 cfs 4.02 4.03
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Table 4: Depth 50 feet upstream of Stockton Avenue Bridge Existing Conditions and Alternative 5 (Clear Span Bridge) Model
Station
218.85
Existing
Conditions
(feet)
Alternative 5
Clear Span
Bridge
(feet)
Q100
17,500 cfs 13.06 12.20
QJan2024
1,200 cfs 4.05 4.02
Conclusions
As seen in Tables 1 and 2, above, with the exception of Alternative 1, the debris fin, water surface elevations on the upstream side of the Stockton Avenue Bridge for Alternatives 2 through 4, are within 6” of the existing condition water surface elevations. The debris diversion fin alternative shows an increase in water surface elevation by 1.5’ at the bridge. This increase is due to a partial blockage of the channel by the eastern fin. The blockage is caused by angling the fin toward the creek wall to deflect LWD away from the narrow span underneath the bridge on its east side.
Further upstream, however, water surface elevations associated with debris countermeasure Alternatives 2 through 4 are lower by 1.4 to 1.7 feet than existing conditions for the 100-year event, indicating a relief in backwater conditions due to the change in LWD capture at the bridge. For the lower flow event, there is negligible difference in water surface elevation upstream due to the installation of Alternatives 2 through 4. Backwater effects upstream are exacerbated by the blockage of the channel caused by the eastern fin for both the 100-year and lower flow event.
Tables 3 and 4 provide a comparison of water surface elevations, for the 100-year and lower flow events, between the bridge in Existing Condition, and the Alternative 5 Clear Span Bridge.
Both scenarios were modeled assuming no debris accumulation in order to compare channel capacity. At the upstream side of the bridge, the water surface elevation increases by 0.2’ for the 100-year event and 0.1’ for the lower flow event. While there is a loss of the existing bridge piers in the middle of the channel for the clear span bridge, the clear span bridge has a deeper deck section which becomes submerged on the eastern side during the 100-year event, causing 287
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a constriction in the model. Upstream of the bridge, water surface elevation goes down with Alternative 5. The increased capacity at the channel bottom under the bridge by removal of the existing bridge piers may be alleviating backwater effects upstream in spite of the new, deeper bridge deck being partially submerged during the 100-year event.
It is noted that at the bridge for the existing condition, the 100-year water surface elevation is slightly less (approximately 5”) for the model which includes debris. This is due to a velocity difference in the channel under the bridge. The model with the debris included indicates that water velocity under the bridge is higher under the debris condition, 13.7 +/- feet per second vs.
10.9 +/- feet per second for the no-debris condition. But while water surface is elevated by 0.2’ at the bridge, further upstream, water surface elevation for the 100-year event is decreased. For the lower flow event, changes in water surface elevation between existing condition and Alternative 5, the clear span bridge, are negligible.
When upstream conditions are compared for the Existing Conditions with Debris (the existing bridge with no diversion measures and capturing debris on the existing bridge piers) and Alternative 5 (clear span bridge), the models show an approximately 2.6 feet decrease in water surface elevation.
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Attachment 1
HEC-RAS Model Results Tables
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Item 9 A.
HEC-RAS Plan: ExCondStead1200 River: SoquelCreek Reach: SoquelCreekUP Profile: PF 1 Reach River Sta Profile E.G. Elev W.S. Elev Crit W.S. Frctn Loss C & E Loss Top Width Q Left Q Channel Q Right Vel Chnl (ft) (ft) (ft) (ft) (ft) (ft) (cfs) (cfs) (cfs) (ft/s)
SoquelCreekUP 203.28 PF 1 4.16 4.07 0.00 0.00 120.81 1200.00 2.44 SoquelCreekUP 195.4 PF 1 4.16 4.07 1.45 0.00 0.01 121.47 1200.00 2.44 SoquelCreekUP 170.36 BR U PF 1 4.15 4.01 1.63 0.02 0.01 101.95 1200.00 2.93 SoquelCreekUP 170.36 BR D PF 1 4.11 4.00 1.50 0.00 0.01 115.03 1200.00 2.61 SoquelCreekUP 145.32 PF 1 4.10 4.01 0.00 0.00 126.03 1200.00 2.38 SoquelCreekUP 140.31 PF 1 4.10 4.01 0.00 0.00 124.07 1200.00 2.42 Existing Condition
Q1200
With Debris
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Item 9 A.
HEC-RAS Plan: ExCondStead1 River: SoquelCreek Reach: SoquelCreekUP Profile: PF 1 Reach River Sta Profile E.G. Elev W.S. Elev Crit W.S. Frctn Loss C & E Loss Top Width Q Left Q Channel Q Right Vel Chnl (ft) (ft) (ft) (ft) (ft) (ft) (cfs) (cfs) (cfs) (ft/s)
SoquelCreekUP 203.28 PF 1 14.96 13.25 0.01 0.02 149.14 17500.00 10.47 SoquelCreekUP 195.4 PF 1 14.93 13.16 8.71 0.01 0.34 148.55 17500.00 10.67 SoquelCreekUP 170.36 BR U PF 1 14.58 11.67 9.65 0.20 0.18 115.52 17500.00 13.68 SoquelCreekUP 170.36 BR D PF 1 14.19 11.64 9.13 0.01 0.26 121.12 17500.00 12.80 SoquelCreekUP 145.32 PF 1 13.93 11.89 0.01 0.00 148.64 17500.00 11.45 SoquelCreekUP 140.31 PF 1 13.92 11.87 0.02 0.09 143.71 17500.00 11.47 Existing Condition
Q17500
With Debris
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Item 9 A.
HEC-RAS Plan: QS 17500 No Debris River: SoquelCreek Reach: SoquelCreekUP Profile: PF 1 Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
SoquelCreekUP 457.43 PF 1 17500.00 0.00 13.82 15.37 0.001307 10.45 2033.18 289.28 0.51 SoquelCreekUP 447.43 PF 1 17500.00 0.00 13.79 15.36 0.001337 10.50 2018.04 288.34 0.52 SoquelCreekUP 433.47 PF 1 17500.00 0.00 13.81 15.33 0.001355 10.28 2033.95 293.08 0.52 SoquelCreekUP 423.47 PF 1 17500.00 0.00 13.79 15.31 0.001363 10.26 2024.38 290.99 0.52 SoquelCreekUP 413.47 PF 1 17500.00 0.00 13.65 15.29 0.001368 10.69 1996.93 293.06 0.52 SoquelCreekUP 393.46 PF 1 17500.00 0.00 13.72 15.22 0.001374 10.10 2017.60 297.27 0.51 SoquelCreekUP 373.46 PF 1 17500.00 0.00 13.56 15.18 0.001446 10.49 1949.61 302.70 0.53 SoquelCreekUP 353.46 PF 1 17500.00 0.00 13.43 15.14 0.001473 10.74 1890.19 297.99 0.54 SoquelCreekUP 333.46 PF 1 17500.00 0.00 13.41 15.10 0.001469 10.65 1888.57 297.93 0.54 SoquelCreekUP 313.46 PF 1 17500.00 0.00 13.24 15.06 0.001492 10.98 1799.80 294.97 0.55 SoquelCreekUP 293.46 PF 1 17500.00 0.00 13.19 15.03 0.001501 10.95 1737.53 296.86 0.55 SoquelCreekUP 273.46 PF 1 17500.00 0.00 13.17 15.00 0.001486 10.93 1698.64 214.35 0.55 SoquelCreekUP 253.46 PF 1 17500.00 0.00 13.29 14.90 0.001922 10.17 1721.48 194.88 0.60 SoquelCreekUP 245.93 PF 1 17500.00 0.00 13.28 14.88 0.001893 10.13 1727.34 193.41 0.60 SoquelCreekUP 228.95 PF 1 17500.00 0.00 13.20 14.84 0.001874 10.26 1705.25 185.14 0.60 SoquelCreekUP 218.85 PF 1 17500.00 0.00 13.06 14.81 0.001641 10.63 1661.97 171.40 0.57 SoquelCreekUP 211.97 PF 1 17500.00 0.00 13.05 14.80 0.001725 10.60 1651.43 158.21 0.58 SoquelCreekUP 203.28 PF 1 17500.00 0.00 12.97 14.77 0.001666 10.74 1629.34 147.62 0.57 SoquelCreekUP 195.4 PF 1 17500.00 0.00 12.89 8.71 14.74 0.001455 10.91 1603.46 147.53 0.56 SoquelCreekUP 170.36 Bridge
SoquelCreekUP 145.32 PF 1 17500.00 0.00 11.89 13.93 0.001851 11.45 1528.91 148.64 0.60 SoquelCreekUP 140.31 PF 1 17500.00 0.00 11.87 13.92 0.002036 11.47 1525.11 143.71 0.62 SoquelCreekUP 130.3 PF 1 17500.00 0.00 11.45 13.80 0.002425 12.31 1421.37 137.80 0.68 SoquelCreekUP 120.28 PF 1 17500.00 0.00 10.98 13.67 0.002923 13.16 1331.51 137.93 0.74 SoquelCreekUP 110.27 PF 1 17500.00 0.00 10.88 9.27 13.64 0.003633 13.34 1312.21 156.21 0.81 SoquelCreekUP 103.87 PF 1 17500.00 0.00 9.62 9.62 13.50 0.005676 15.80 1111.51 147.73 1.00 SoquelCreekUP 86.16 PF 1 17500.00 0.00 8.15 8.15 12.16 0.005653 16.06 1090.40 139.30 1.00 SoquelCreekUP 76.02 PF 1 17500.00 0.00 7.37 7.37 11.05 0.005689 15.38 1137.69 154.86 1.00 SoquelCreekUP 65.88 PF 1 17500.00 0.00 6.92 6.92 10.38 0.005723 14.92 1173.01 169.85 1.00 SoquelCreekUP 59.74 PF 1 17500.00 0.00 6.73 6.73 10.09 0.005734 14.70 1190.18 177.25 1.00 SoquelCreekUP 49.6 PF 1 17500.00 0.00 6.97 6.49 9.78 0.004561 13.44 1302.23 187.14 0.90 SoquelCreekUP 38.98 PF 1 17500.00 0.00 7.30 9.57 0.003460 12.08 1448.60 198.82 0.79 SoquelCreekUP 28.98 PF 1 17500.00 0.00 7.44 9.46 0.003134 11.41 1533.92 206.96 0.74 SoquelCreekUP 18.98 PF 1 17500.00 0.00 7.23 9.41 0.003478 11.86 1475.24 211.82 0.79 SoquelCreekUP 10 PF 1 17500.00 0.00 7.16 6.26 9.38 0.003730 11.96 1462.96 219.52 0.82 SoquelCreekUP 0 PF 1 17500.00 0.00 6.41 6.41 9.27 0.005792 13.56 1290.64 226.00 1.00 Existing Condition
Q17500
No Debris
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HEC-RAS Plan: PCOpt117500 River: SoquelCreek Reach: SoquelCreekUP Profile: PF 1 Reach River Sta Profile E.G. Elev W.S. Elev Crit W.S. Frctn Loss C & E Loss Top Width Q Left Q Channel Q Right Vel Chnl (ft) (ft) (ft) (ft) (ft) (ft) (cfs) (cfs) (cfs) (ft/s)
SoquelCreekUP 203.28 PF 1 18.71 17.95 0.05 0.31 327.16 335.08 17164.93 7.05 SoquelCreekUP 195.4 PF 1 18.35 16.55 12.58 0.01 0.86 235.59 9.77 17490.23 10.77 SoquelCreekUP 170.36 BR U PF 1 17.48 12.82 12.82 0.24 1.06 108.41 17500.00 17.32 SoquelCreekUP 170.36 BR D PF 1 14.19 11.64 9.13 0.01 0.26 121.12 17500.00 12.80 SoquelCreekUP 145.32 PF 1 13.93 11.89 0.01 0.00 148.64 17500.00 11.45 SoquelCreekUP 140.31 PF 1 13.92 11.87 0.02 0.09 143.71 17500.00 11.47 Alternative 1
Q17500
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Item 9 A.
HEC-RAS Plan: Opt2QS1200 River: SoquelCreek Reach: SoquelCreekUP Profile: PF 1 Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
SoquelCreekUP 457.43 PF 1 1200.00 0.00 4.24 4.35 0.000356 2.68 447.13 105.78 0.23 SoquelCreekUP 447.43 PF 1 1200.00 0.00 4.24 4.35 0.000352 2.67 449.28 106.26 0.23 SoquelCreekUP 433.47 PF 1 1200.00 0.00 4.23 4.34 0.000348 2.65 452.30 107.07 0.23 SoquelCreekUP 423.47 PF 1 1200.00 0.00 4.23 4.34 0.000345 2.64 454.47 107.65 0.23 SoquelCreekUP 413.47 PF 1 1200.00 0.00 4.23 4.34 0.000341 2.63 456.63 108.23 0.23 SoquelCreekUP 393.46 PF 1 1200.00 0.00 4.22 4.33 0.000335 2.60 460.98 109.40 0.22 SoquelCreekUP 373.46 PF 1 1200.00 0.00 4.22 4.32 0.000329 2.58 465.31 110.56 0.22 SoquelCreekUP 353.46 PF 1 1200.00 0.00 4.21 4.31 0.000323 2.56 469.61 111.73 0.22 SoquelCreekUP 333.46 PF 1 1200.00 0.00 4.21 4.31 0.000318 2.53 473.94 112.89 0.22 SoquelCreekUP 313.46 PF 1 1200.00 0.00 4.20 4.30 0.000312 2.51 478.26 114.06 0.22 SoquelCreekUP 293.46 PF 1 1200.00 0.00 4.20 4.29 0.000307 2.49 482.59 115.23 0.21 SoquelCreekUP 273.46 PF 1 1200.00 0.00 4.19 4.29 0.000302 2.46 486.90 116.39 0.21 SoquelCreekUP 253.46 PF 1 1200.00 0.00 4.19 4.28 0.000296 2.44 491.19 117.55 0.21 SoquelCreekUP 245.93 PF 1 1200.00 0.00 4.19 4.28 0.000295 2.43 492.85 117.99 0.21 SoquelCreekUP 228.95 PF 1 1200.00 0.00 4.18 4.27 0.000290 2.42 496.48 118.98 0.21 SoquelCreekUP 218.85 PF 1 1200.00 0.00 4.18 4.27 0.000288 2.41 498.60 119.55 0.21 SoquelCreekUP 216 PF 1 1200.00 0.00 4.18 1.46 4.27 0.000286 2.40 500.05 119.95 0.21 SoquelCreekUP 204.45 Bridge
SoquelCreekUP 193.2 PF 1 1200.00 0.00 4.08 4.17 0.000291 2.43 492.98 121.47 0.21 SoquelCreekUP 193.1 PF 1 1200.00 0.00 4.06 4.16 0.000294 2.44 491.10 121.47 0.21 SoquelCreekUP 193 PF 1 1200.00 0.00 4.05 1.45 4.14 0.000298 2.45 489.17 121.47 0.22 SoquelCreekUP 170.36 Bridge
SoquelCreekUP 145.32 PF 1 1200.00 0.00 4.01 4.10 0.000294 2.38 505.04 126.03 0.21 SoquelCreekUP 140.31 PF 1 1200.00 0.00 4.01 4.10 0.000305 2.42 496.53 124.07 0.21 SoquelCreekUP 130.3 PF 1 1200.00 0.00 4.00 4.09 0.000324 2.48 483.37 121.08 0.22 SoquelCreekUP 120.28 PF 1 1200.00 0.00 3.99 4.09 0.000344 2.55 470.22 118.09 0.23 SoquelCreekUP 110.27 PF 1 1200.00 0.00 3.98 4.08 0.000366 2.62 457.24 115.10 0.23 SoquelCreekUP 103.87 PF 1 1200.00 0.00 3.97 4.08 0.000387 2.69 445.35 112.37 0.24 SoquelCreekUP 86.16 PF 1 1200.00 0.00 3.99 4.07 0.000266 2.26 531.51 133.52 0.20 SoquelCreekUP 76.02 PF 1 1200.00 0.00 4.00 4.06 0.000196 1.95 616.19 154.32 0.17 SoquelCreekUP 65.88 PF 1 1200.00 0.00 4.00 4.05 0.000161 1.77 677.47 169.42 0.16 SoquelCreekUP 59.74 PF 1 1200.00 0.00 4.00 4.05 0.000147 1.70 707.58 176.85 0.15 SoquelCreekUP 49.6 PF 1 1200.00 0.00 4.01 4.05 0.000131 1.61 747.58 186.74 0.14 SoquelCreekUP 38.98 PF 1 1200.00 0.00 4.01 4.04 0.000116 1.51 794.27 198.32 0.13 SoquelCreekUP 28.98 PF 1 1200.00 0.00 4.01 4.04 0.000107 1.46 824.57 206.33 0.13 SoquelCreekUP 18.98 PF 1 1200.00 0.00 4.01 4.04 0.000117 1.49 804.02 206.12 0.13 SoquelCreekUP 10 PF 1 1200.00 0.00 4.00 4.04 0.000123 1.52 791.15 206.16 0.14 SoquelCreekUP 0 PF 1 1200.00 0.00 4.00 1.32 4.04 0.000138 1.57 766.39 209.47 0.14 Alternative 2
Q1200
294
Item 9 A.
HEC-RAS Plan: Opt2QS17500 River: SoquelCreek Reach: SoquelCreekUP Profile: PF 1 Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
SoquelCreekUP 457.43 PF 1 17500.00 0.00 14.85 16.05 0.000950 9.31 2336.19 297.43 0.44 SoquelCreekUP 447.43 PF 1 17500.00 0.00 14.83 16.04 0.000967 9.34 2323.40 296.52 0.44 SoquelCreekUP 433.47 PF 1 17500.00 0.00 14.85 16.01 0.000974 9.13 2343.73 301.52 0.44 SoquelCreekUP 423.47 PF 1 17500.00 0.00 14.84 16.00 0.000985 9.12 2333.31 300.12 0.44 SoquelCreekUP 413.47 PF 1 17500.00 0.00 14.76 15.99 0.000978 9.45 2324.77 301.99 0.44 SoquelCreekUP 393.46 PF 1 17500.00 0.00 14.80 15.94 0.000971 8.95 2341.85 304.84 0.44 SoquelCreekUP 373.46 PF 1 17500.00 0.00 14.71 15.92 0.001003 9.20 2304.51 313.17 0.45 SoquelCreekUP 353.46 PF 1 17500.00 0.00 14.62 15.89 0.001013 9.40 2252.35 308.12 0.45 SoquelCreekUP 333.46 PF 1 17500.00 0.00 14.62 15.86 0.001008 9.30 2253.42 308.92 0.45 SoquelCreekUP 313.46 PF 1 17500.00 0.00 14.49 15.83 0.001006 9.61 2175.55 306.77 0.46 SoquelCreekUP 293.46 PF 1 17500.00 0.00 14.43 15.81 0.001022 9.63 2112.24 308.75 0.46 SoquelCreekUP 273.46 PF 1 17500.00 0.00 14.33 15.78 0.001063 9.81 2025.39 309.02 0.47 SoquelCreekUP 253.46 PF 1 17500.00 0.00 14.46 15.69 0.001364 8.90 2014.82 305.21 0.51 SoquelCreekUP 245.93 PF 1 17500.00 0.00 14.45 15.68 0.001338 8.88 2015.14 301.75 0.51 SoquelCreekUP 228.95 PF 1 17500.00 0.00 14.39 15.65 0.001360 9.02 1967.84 298.82 0.51 SoquelCreekUP 218.85 PF 1 17500.00 0.00 14.20 15.62 0.001192 9.58 1876.80 227.45 0.49 SoquelCreekUP 216 PF 1 17500.00 0.00 14.21 8.78 15.60 0.001349 9.47 1855.09 210.80 0.51 SoquelCreekUP 204.45 Bridge
SoquelCreekUP 193.2 PF 1 17500.00 0.00 13.11 14.89 0.001367 10.71 1633.96 148.35 0.54 SoquelCreekUP 193.1 PF 1 17500.00 0.00 13.00 14.81 0.001411 10.81 1618.60 147.94 0.55 SoquelCreekUP 193 PF 1 17500.00 0.00 12.88 8.71 14.73 0.001457 10.92 1602.85 147.52 0.56 SoquelCreekUP 170.36 Bridge
SoquelCreekUP 145.32 PF 1 17500.00 0.00 11.89 13.93 0.001851 11.45 1528.91 148.64 0.60 SoquelCreekUP 140.31 PF 1 17500.00 0.00 11.87 13.92 0.002036 11.47 1525.11 143.71 0.62 SoquelCreekUP 130.3 PF 1 17500.00 0.00 11.45 13.80 0.002425 12.31 1421.37 137.80 0.68 SoquelCreekUP 120.28 PF 1 17500.00 0.00 10.98 13.67 0.002923 13.16 1331.51 137.93 0.74 SoquelCreekUP 110.27 PF 1 17500.00 0.00 10.88 9.27 13.64 0.003633 13.34 1312.21 156.21 0.81 SoquelCreekUP 103.87 PF 1 17500.00 0.00 9.62 9.62 13.50 0.005676 15.80 1111.51 147.73 1.00 SoquelCreekUP 86.16 PF 1 17500.00 0.00 8.15 8.15 12.16 0.005653 16.06 1090.40 139.30 1.00 SoquelCreekUP 76.02 PF 1 17500.00 0.00 7.37 7.37 11.05 0.005689 15.38 1137.69 154.86 1.00 SoquelCreekUP 65.88 PF 1 17500.00 0.00 6.92 6.92 10.38 0.005723 14.92 1173.01 169.85 1.00 SoquelCreekUP 59.74 PF 1 17500.00 0.00 6.73 6.73 10.09 0.005734 14.70 1190.18 177.25 1.00 SoquelCreekUP 49.6 PF 1 17500.00 0.00 6.97 6.49 9.78 0.004561 13.44 1302.23 187.14 0.90 SoquelCreekUP 38.98 PF 1 17500.00 0.00 7.30 9.57 0.003460 12.08 1448.60 198.82 0.79 SoquelCreekUP 28.98 PF 1 17500.00 0.00 7.44 9.46 0.003134 11.41 1533.92 206.96 0.74 SoquelCreekUP 18.98 PF 1 17500.00 0.00 7.23 9.41 0.003478 11.86 1475.24 211.82 0.79 SoquelCreekUP 10 PF 1 17500.00 0.00 7.16 6.26 9.38 0.003730 11.96 1462.96 219.52 0.82 SoquelCreekUP 0 PF 1 17500.00 0.00 6.41 6.41 9.27 0.005792 13.56 1290.64 226.00 1.00 Alternative 2
Q17500
295
Item 9 A.
HEC-RAS Plan: Opt3QS1200 River: SoquelCreek Reach: SoquelCreekUP Profile: PF 1 Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
SoquelCreekUP 457.43 PF 1 1200.00 0.00 4.23 4.34 0.000359 2.69 445.98 105.77 0.23 SoquelCreekUP 447.43 PF 1 1200.00 0.00 4.23 4.34 0.000355 2.68 448.13 106.26 0.23 SoquelCreekUP 433.47 PF 1 1200.00 0.00 4.22 4.33 0.000351 2.66 451.14 107.07 0.23 SoquelCreekUP 423.47 PF 1 1200.00 0.00 4.22 4.33 0.000348 2.65 453.29 107.65 0.23 SoquelCreekUP 413.47 PF 1 1200.00 0.00 4.22 4.32 0.000344 2.63 455.45 108.23 0.23 SoquelCreekUP 393.46 PF 1 1200.00 0.00 4.21 4.32 0.000338 2.61 459.78 109.39 0.22 SoquelCreekUP 373.46 PF 1 1200.00 0.00 4.21 4.31 0.000332 2.59 464.08 110.56 0.22 SoquelCreekUP 353.46 PF 1 1200.00 0.00 4.20 4.30 0.000326 2.56 468.37 111.72 0.22 SoquelCreekUP 333.46 PF 1 1200.00 0.00 4.20 4.30 0.000320 2.54 472.68 112.89 0.22 SoquelCreekUP 313.46 PF 1 1200.00 0.00 4.19 4.29 0.000315 2.52 476.98 114.05 0.22 SoquelCreekUP 293.46 PF 1 1200.00 0.00 4.19 4.28 0.000309 2.49 481.29 115.23 0.22 SoquelCreekUP 273.46 PF 1 1200.00 0.00 4.18 4.28 0.000304 2.47 485.58 116.38 0.21 SoquelCreekUP 253.46 PF 1 1200.00 0.00 4.18 4.27 0.000299 2.45 489.86 117.55 0.21 SoquelCreekUP 245.93 PF 1 1200.00 0.00 4.17 4.27 0.000297 2.44 491.51 117.99 0.21 SoquelCreekUP 228.95 PF 1 1200.00 0.00 4.17 4.26 0.000293 2.42 495.12 118.98 0.21 SoquelCreekUP 218.85 PF 1 1200.00 0.00 4.17 1.46 4.26 0.000291 2.41 497.23 119.55 0.21 SoquelCreekUP 205.45 Bridge
SoquelCreekUP 193.2 PF 1 1200.00 0.00 4.08 4.17 0.000291 2.43 492.98 121.47 0.21 SoquelCreekUP 193.1 PF 1 1200.00 0.00 4.06 4.16 0.000294 2.44 491.10 121.47 0.21 SoquelCreekUP 193 PF 1 1200.00 0.00 4.05 1.45 4.14 0.000298 2.45 489.17 121.47 0.22 SoquelCreekUP 170.36 Bridge
SoquelCreekUP 145.32 PF 1 1200.00 0.00 4.01 4.10 0.000294 2.38 505.04 126.03 0.21 SoquelCreekUP 140.31 PF 1 1200.00 0.00 4.01 4.10 0.000305 2.42 496.53 124.07 0.21 SoquelCreekUP 130.3 PF 1 1200.00 0.00 4.00 4.09 0.000324 2.48 483.37 121.08 0.22 SoquelCreekUP 120.28 PF 1 1200.00 0.00 3.99 4.09 0.000344 2.55 470.22 118.09 0.23 SoquelCreekUP 110.27 PF 1 1200.00 0.00 3.98 4.08 0.000366 2.62 457.24 115.10 0.23 SoquelCreekUP 103.87 PF 1 1200.00 0.00 3.97 4.08 0.000387 2.69 445.35 112.37 0.24 SoquelCreekUP 86.16 PF 1 1200.00 0.00 3.99 4.07 0.000266 2.26 531.51 133.52 0.20 SoquelCreekUP 76.02 PF 1 1200.00 0.00 4.00 4.06 0.000196 1.95 616.19 154.32 0.17 SoquelCreekUP 65.88 PF 1 1200.00 0.00 4.00 4.05 0.000161 1.77 677.47 169.42 0.16 SoquelCreekUP 59.74 PF 1 1200.00 0.00 4.00 4.05 0.000147 1.70 707.58 176.85 0.15 SoquelCreekUP 49.6 PF 1 1200.00 0.00 4.01 4.05 0.000131 1.61 747.58 186.74 0.14 SoquelCreekUP 38.98 PF 1 1200.00 0.00 4.01 4.04 0.000116 1.51 794.27 198.32 0.13 SoquelCreekUP 28.98 PF 1 1200.00 0.00 4.01 4.04 0.000107 1.46 824.57 206.33 0.13 SoquelCreekUP 18.98 PF 1 1200.00 0.00 4.01 4.04 0.000117 1.49 804.02 206.12 0.13 SoquelCreekUP 10 PF 1 1200.00 0.00 4.00 4.04 0.000123 1.52 791.15 206.16 0.14 SoquelCreekUP 0 PF 1 1200.00 0.00 4.00 1.32 4.04 0.000138 1.57 766.39 209.47 0.14 Alternative 3
Q1200
296
Item 9 A.
HEC-RAS Plan: Opt3QS17500 River: SoquelCreek Reach: SoquelCreekUP Profile: PF 1 Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
SoquelCreekUP 457.43 PF 1 17500.00 0.00 14.58 15.87 0.001029 9.59 2257.76 295.35 0.46 SoquelCreekUP 447.43 PF 1 17500.00 0.00 14.57 15.86 0.001048 9.62 2244.73 294.44 0.46 SoquelCreekUP 433.47 PF 1 17500.00 0.00 14.58 15.83 0.001057 9.41 2263.94 299.38 0.46 SoquelCreekUP 423.47 PF 1 17500.00 0.00 14.57 15.82 0.001068 9.39 2253.59 297.72 0.46 SoquelCreekUP 413.47 PF 1 17500.00 0.00 14.48 15.80 0.001062 9.74 2241.30 299.66 0.46 SoquelCreekUP 393.46 PF 1 17500.00 0.00 14.53 15.75 0.001058 9.22 2259.18 302.91 0.45 SoquelCreekUP 373.46 PF 1 17500.00 0.00 14.43 15.72 0.001096 9.50 2215.17 310.58 0.47 SoquelCreekUP 353.46 PF 1 17500.00 0.00 14.33 15.69 0.001108 9.71 2161.81 305.54 0.47 SoquelCreekUP 333.46 PF 1 17500.00 0.00 14.32 15.66 0.001104 9.61 2162.26 306.20 0.47 SoquelCreekUP 313.46 PF 1 17500.00 0.00 14.18 15.63 0.001106 9.93 2081.84 304.14 0.48 SoquelCreekUP 293.46 PF 1 17500.00 0.00 14.13 15.61 0.001122 9.94 2018.54 306.06 0.48 SoquelCreekUP 273.46 PF 1 17500.00 0.00 14.02 15.57 0.001167 10.13 1929.74 306.18 0.49 SoquelCreekUP 253.46 PF 1 17500.00 0.00 14.16 15.48 0.001518 9.22 1922.52 301.62 0.54 SoquelCreekUP 245.93 PF 1 17500.00 0.00 14.15 15.46 0.001492 9.19 1923.76 298.84 0.53 SoquelCreekUP 228.95 PF 1 17500.00 0.00 14.08 15.43 0.001511 9.33 1881.73 253.06 0.54 SoquelCreekUP 218.85 PF 1 17500.00 0.00 13.90 8.78 15.40 0.001292 9.84 1813.46 191.79 0.51 SoquelCreekUP 205.45 Bridge
SoquelCreekUP 193.2 PF 1 17500.00 0.00 13.11 14.89 0.001367 10.71 1633.96 148.35 0.54 SoquelCreekUP 193.1 PF 1 17500.00 0.00 13.00 14.81 0.001411 10.81 1618.60 147.94 0.55 SoquelCreekUP 193 PF 1 17500.00 0.00 12.88 8.71 14.73 0.001457 10.92 1602.85 147.52 0.56 SoquelCreekUP 170.36 Bridge
SoquelCreekUP 145.32 PF 1 17500.00 0.00 11.89 13.93 0.001851 11.45 1528.91 148.64 0.60 SoquelCreekUP 140.31 PF 1 17500.00 0.00 11.87 13.92 0.002036 11.47 1525.11 143.71 0.62 SoquelCreekUP 130.3 PF 1 17500.00 0.00 11.45 13.80 0.002425 12.31 1421.37 137.80 0.68 SoquelCreekUP 120.28 PF 1 17500.00 0.00 10.98 13.67 0.002923 13.16 1331.51 137.93 0.74 SoquelCreekUP 110.27 PF 1 17500.00 0.00 10.88 9.27 13.64 0.003633 13.34 1312.21 156.21 0.81 SoquelCreekUP 103.87 PF 1 17500.00 0.00 9.62 9.62 13.50 0.005676 15.80 1111.51 147.73 1.00 SoquelCreekUP 86.16 PF 1 17500.00 0.00 8.15 8.15 12.16 0.005653 16.06 1090.40 139.30 1.00 SoquelCreekUP 76.02 PF 1 17500.00 0.00 7.37 7.37 11.05 0.005689 15.38 1137.69 154.86 1.00 SoquelCreekUP 65.88 PF 1 17500.00 0.00 6.92 6.92 10.38 0.005723 14.92 1173.01 169.85 1.00 SoquelCreekUP 59.74 PF 1 17500.00 0.00 6.73 6.73 10.09 0.005734 14.70 1190.18 177.25 1.00 SoquelCreekUP 49.6 PF 1 17500.00 0.00 6.97 6.49 9.78 0.004561 13.44 1302.23 187.14 0.90 SoquelCreekUP 38.98 PF 1 17500.00 0.00 7.30 9.57 0.003460 12.08 1448.60 198.82 0.79 SoquelCreekUP 28.98 PF 1 17500.00 0.00 7.44 9.46 0.003134 11.41 1533.92 206.96 0.74 SoquelCreekUP 18.98 PF 1 17500.00 0.00 7.23 9.41 0.003478 11.86 1475.24 211.82 0.79 SoquelCreekUP 10 PF 1 17500.00 0.00 7.16 6.26 9.38 0.003730 11.96 1462.96 219.52 0.82 SoquelCreekUP 0 PF 1 17500.00 0.00 6.41 6.41 9.27 0.005792 13.56 1290.64 226.00 1.00 Alternative 3
Q17500
297
Item 9 A.
HEC-RAS Plan: Opt4QS1200 River: SoquelCreek Reach: SoquelCreekUP Profile: PF 1 Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
SoquelCreekUP 457.43 PF 1 1200.00 0.00 4.24 4.35 0.000357 2.69 446.84 105.78 0.23 SoquelCreekUP 447.43 PF 1 1200.00 0.00 4.23 4.35 0.000353 2.67 448.99 106.26 0.23 SoquelCreekUP 433.47 PF 1 1200.00 0.00 4.23 4.34 0.000349 2.65 452.00 107.07 0.23 SoquelCreekUP 423.47 PF 1 1200.00 0.00 4.23 4.34 0.000345 2.64 454.17 107.65 0.23 SoquelCreekUP 413.47 PF 1 1200.00 0.00 4.23 4.33 0.000342 2.63 456.33 108.23 0.23 SoquelCreekUP 393.46 PF 1 1200.00 0.00 4.22 4.33 0.000336 2.60 460.67 109.39 0.22 SoquelCreekUP 373.46 PF 1 1200.00 0.00 4.21 4.32 0.000330 2.58 464.99 110.56 0.22 SoquelCreekUP 353.46 PF 1 1200.00 0.00 4.21 4.31 0.000324 2.56 469.29 111.73 0.22 SoquelCreekUP 333.46 PF 1 1200.00 0.00 4.20 4.30 0.000318 2.53 473.62 112.89 0.22 SoquelCreekUP 313.46 PF 1 1200.00 0.00 4.20 4.30 0.000313 2.51 477.93 114.06 0.22 SoquelCreekUP 293.46 PF 1 1200.00 0.00 4.19 4.29 0.000307 2.49 482.25 115.23 0.21 SoquelCreekUP 273.46 PF 1 1200.00 0.00 4.19 4.28 0.000302 2.47 486.56 116.39 0.21 SoquelCreekUP 253.46 PF 1 1200.00 0.00 4.18 4.28 0.000297 2.44 490.85 117.55 0.21 SoquelCreekUP 245.93 PF 1 1200.00 0.00 4.18 4.27 0.000295 2.44 492.50 117.99 0.21 SoquelCreekUP 228.95 PF 1 1200.00 0.00 4.18 4.27 0.000291 2.42 496.13 118.98 0.21 SoquelCreekUP 218.85 PF 1 1200.00 0.00 4.18 4.27 0.000289 2.41 498.25 119.55 0.21 SoquelCreekUP 216 PF 1 1200.00 0.00 4.17 4.26 0.000289 2.41 498.01 119.55 0.21 SoquelCreekUP 211.97 PF 1 1200.00 0.00 4.17 4.26 0.000287 2.40 499.45 119.95 0.21 SoquelCreekUP 206 PF 1 1200.00 0.00 4.17 4.26 0.000284 2.39 502.91 120.83 0.21 SoquelCreekUP 203.28 PF 1 1200.00 0.00 4.17 4.26 0.000284 2.39 502.62 120.83 0.21 SoquelCreekUP 199 PF 1 1200.00 0.00 4.17 1.45 4.25 0.000271 2.38 503.49 121.48 0.21 SoquelCreekUP 196.94 Bridge
SoquelCreekUP 193.2 PF 1 1200.00 0.00 4.10 4.19 0.000286 2.42 495.52 121.47 0.21 SoquelCreekUP 193.1 PF 1 1200.00 0.00 4.08 4.18 0.000289 2.43 493.68 121.47 0.21 SoquelCreekUP 193 PF 1 1200.00 0.00 4.07 1.45 4.16 0.000293 2.44 491.76 121.47 0.21 SoquelCreekUP 170.36 Bridge
SoquelCreekUP 145.32 PF 1 1200.00 0.00 4.01 4.10 0.000294 2.38 505.04 126.03 0.21 SoquelCreekUP 140.31 PF 1 1200.00 0.00 4.01 4.10 0.000305 2.42 496.53 124.07 0.21 SoquelCreekUP 130.3 PF 1 1200.00 0.00 4.00 4.09 0.000324 2.48 483.37 121.08 0.22 SoquelCreekUP 120.28 PF 1 1200.00 0.00 3.99 4.09 0.000344 2.55 470.22 118.09 0.23 SoquelCreekUP 110.27 PF 1 1200.00 0.00 3.98 4.08 0.000366 2.62 457.24 115.10 0.23 SoquelCreekUP 103.87 PF 1 1200.00 0.00 3.97 4.08 0.000387 2.69 445.35 112.37 0.24 SoquelCreekUP 86.16 PF 1 1200.00 0.00 3.99 4.07 0.000266 2.26 531.51 133.52 0.20 SoquelCreekUP 76.02 PF 1 1200.00 0.00 4.00 4.06 0.000196 1.95 616.19 154.32 0.17 SoquelCreekUP 65.88 PF 1 1200.00 0.00 4.00 4.05 0.000161 1.77 677.47 169.42 0.16 SoquelCreekUP 59.74 PF 1 1200.00 0.00 4.00 4.05 0.000147 1.70 707.58 176.85 0.15 SoquelCreekUP 49.6 PF 1 1200.00 0.00 4.01 4.05 0.000131 1.61 747.58 186.74 0.14 SoquelCreekUP 38.98 PF 1 1200.00 0.00 4.01 4.04 0.000116 1.51 794.27 198.32 0.13 SoquelCreekUP 28.98 PF 1 1200.00 0.00 4.01 4.04 0.000107 1.46 824.57 206.33 0.13 SoquelCreekUP 18.98 PF 1 1200.00 0.00 4.01 4.04 0.000117 1.49 804.02 206.12 0.13 SoquelCreekUP 10 PF 1 1200.00 0.00 4.00 4.04 0.000123 1.52 791.15 206.16 0.14 SoquelCreekUP 0 PF 1 1200.00 0.00 4.00 1.32 4.04 0.000138 1.57 766.39 209.47 0.14 Alternative 4
Q1200
298
Item 9 A.
HEC-RAS Plan: Opt4QS17500 River: SoquelCreek Reach: SoquelCreekUP Profile: PF 1 Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
SoquelCreekUP 457.43 PF 1 17500.00 0.00 14.82 16.03 0.000957 9.34 2328.16 297.23 0.44 SoquelCreekUP 447.43 PF 1 17500.00 0.00 14.80 16.02 0.000975 9.37 2315.35 296.31 0.45 SoquelCreekUP 433.47 PF 1 17500.00 0.00 14.82 15.99 0.000982 9.16 2335.57 301.30 0.45 SoquelCreekUP 423.47 PF 1 17500.00 0.00 14.81 15.99 0.000993 9.15 2325.16 299.87 0.45 SoquelCreekUP 413.47 PF 1 17500.00 0.00 14.73 15.97 0.000986 9.47 2316.26 301.75 0.44 SoquelCreekUP 393.46 PF 1 17500.00 0.00 14.77 15.92 0.000979 8.98 2333.41 304.64 0.44 SoquelCreekUP 373.46 PF 1 17500.00 0.00 14.68 15.89 0.001012 9.23 2295.41 312.91 0.45 SoquelCreekUP 353.46 PF 1 17500.00 0.00 14.59 15.87 0.001022 9.43 2243.15 307.86 0.45 SoquelCreekUP 333.46 PF 1 17500.00 0.00 14.59 15.84 0.001017 9.34 2244.16 308.64 0.45 SoquelCreekUP 313.46 PF 1 17500.00 0.00 14.46 15.81 0.001016 9.64 2166.05 306.51 0.46 SoquelCreekUP 293.46 PF 1 17500.00 0.00 14.40 15.79 0.001032 9.66 2102.58 308.47 0.46 SoquelCreekUP 273.46 PF 1 17500.00 0.00 14.30 15.76 0.001073 9.84 2015.51 308.73 0.47 SoquelCreekUP 253.46 PF 1 17500.00 0.00 14.43 15.67 0.001379 8.93 2005.27 304.83 0.52 SoquelCreekUP 245.93 PF 1 17500.00 0.00 14.42 15.65 0.001353 8.91 2005.69 301.45 0.51 SoquelCreekUP 228.95 PF 1 17500.00 0.00 14.35 15.63 0.001375 9.06 1958.40 298.51 0.52 SoquelCreekUP 218.85 PF 1 17500.00 0.00 14.17 15.60 0.001203 9.61 1869.82 225.95 0.49 SoquelCreekUP 216 PF 1 17500.00 0.00 14.16 15.59 0.001206 9.62 1867.36 225.42 0.49 SoquelCreekUP 211.97 PF 1 17500.00 0.00 14.17 15.57 0.001366 9.50 1846.33 209.10 0.52 SoquelCreekUP 206 PF 1 17500.00 0.00 14.06 15.54 0.001281 9.76 1792.39 175.32 0.50 SoquelCreekUP 203.28 PF 1 17500.00 0.00 14.04 15.53 0.001285 9.77 1790.35 174.81 0.51 SoquelCreekUP 199 PF 1 17500.00 0.00 13.93 8.71 15.49 0.001099 10.03 1744.56 151.65 0.49 SoquelCreekUP 196.94 Bridge
SoquelCreekUP 193.2 PF 1 17500.00 0.00 13.36 15.07 0.001278 10.50 1667.22 149.36 0.53 SoquelCreekUP 193.1 PF 1 17500.00 0.00 13.26 15.00 0.001314 10.58 1653.42 148.95 0.53 SoquelCreekUP 193 PF 1 17500.00 0.00 13.14 8.71 14.92 0.001355 10.68 1638.31 148.49 0.54 SoquelCreekUP 170.36 Bridge
SoquelCreekUP 145.32 PF 1 17500.00 0.00 11.89 13.93 0.001851 11.45 1528.91 148.64 0.60 SoquelCreekUP 140.31 PF 1 17500.00 0.00 11.87 13.92 0.002036 11.47 1525.11 143.71 0.62 SoquelCreekUP 130.3 PF 1 17500.00 0.00 11.45 13.80 0.002425 12.31 1421.37 137.80 0.68 SoquelCreekUP 120.28 PF 1 17500.00 0.00 10.98 13.67 0.002923 13.16 1331.51 137.93 0.74 SoquelCreekUP 110.27 PF 1 17500.00 0.00 10.88 9.27 13.64 0.003633 13.34 1312.21 156.21 0.81 SoquelCreekUP 103.87 PF 1 17500.00 0.00 9.62 9.62 13.50 0.005676 15.80 1111.51 147.73 1.00 SoquelCreekUP 86.16 PF 1 17500.00 0.00 8.15 8.15 12.16 0.005653 16.06 1090.40 139.30 1.00 SoquelCreekUP 76.02 PF 1 17500.00 0.00 7.37 7.37 11.05 0.005689 15.38 1137.69 154.86 1.00 SoquelCreekUP 65.88 PF 1 17500.00 0.00 6.92 6.92 10.38 0.005723 14.92 1173.01 169.85 1.00 SoquelCreekUP 59.74 PF 1 17500.00 0.00 6.73 6.73 10.09 0.005734 14.70 1190.18 177.25 1.00 SoquelCreekUP 49.6 PF 1 17500.00 0.00 6.97 6.49 9.78 0.004561 13.44 1302.23 187.14 0.90 SoquelCreekUP 38.98 PF 1 17500.00 0.00 7.30 9.57 0.003460 12.08 1448.60 198.82 0.79 SoquelCreekUP 28.98 PF 1 17500.00 0.00 7.44 9.46 0.003134 11.41 1533.92 206.96 0.74 Alternative 4
Q17500
299
Item 9 A.
HEC-RAS Plan: Opt4QS17500 River: SoquelCreek Reach: SoquelCreekUP Profile: PF 1 (Continued) Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
SoquelCreekUP 18.98 PF 1 17500.00 0.00 7.23 9.41 0.003478 11.86 1475.24 211.82 0.79 SoquelCreekUP 10 PF 1 17500.00 0.00 7.16 6.26 9.38 0.003730 11.96 1462.96 219.52 0.82 SoquelCreekUP 0 PF 1 17500.00 0.00 6.41 6.41 9.27 0.005792 13.56 1290.64 226.00 1.00 Alternative 4
Q17500
300
Item 9 A.
HEC-RAS Plan: Opt5QS1200 River: SoquelCreek Reach: SoquelCreekUP Profile: PF 1 Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
SoquelCreekUP 457.43 PF 1 1200.00 0.00 4.10 4.22 0.000397 2.78 432.30 105.69 0.24 SoquelCreekUP 447.43 PF 1 1200.00 0.00 4.10 4.22 0.000393 2.76 434.34 106.24 0.24 SoquelCreekUP 433.47 PF 1 1200.00 0.00 4.09 4.21 0.000388 2.74 437.19 107.04 0.24 SoquelCreekUP 423.47 PF 1 1200.00 0.00 4.09 4.21 0.000385 2.73 439.23 107.63 0.24 SoquelCreekUP 413.47 PF 1 1200.00 0.00 4.09 4.20 0.000381 2.72 441.27 108.21 0.24 SoquelCreekUP 393.46 PF 1 1200.00 0.00 4.08 4.19 0.000375 2.69 445.38 109.37 0.24 SoquelCreekUP 373.46 PF 1 1200.00 0.00 4.07 4.18 0.000368 2.67 449.45 110.53 0.23 SoquelCreekUP 353.46 PF 1 1200.00 0.00 4.07 4.18 0.000362 2.65 453.51 111.70 0.23 SoquelCreekUP 333.46 PF 1 1200.00 0.00 4.06 4.17 0.000356 2.62 457.59 112.86 0.23 SoquelCreekUP 313.46 PF 1 1200.00 0.00 4.06 4.16 0.000350 2.60 461.66 114.03 0.23 SoquelCreekUP 293.46 PF 1 1200.00 0.00 4.05 4.15 0.000344 2.58 465.74 115.20 0.23 SoquelCreekUP 273.46 PF 1 1200.00 0.00 4.04 4.15 0.000339 2.55 469.80 116.36 0.22 SoquelCreekUP 253.46 PF 1 1200.00 0.00 4.04 4.14 0.000333 2.53 473.84 117.53 0.22 SoquelCreekUP 245.93 PF 1 1200.00 0.00 4.04 4.14 0.000331 2.52 475.40 117.97 0.22 SoquelCreekUP 228.95 PF 1 1200.00 0.00 4.03 4.13 0.000327 2.51 478.81 118.96 0.22 SoquelCreekUP 218.85 PF 1 1200.00 0.00 4.03 4.13 0.000324 2.50 480.82 119.53 0.22 SoquelCreekUP 211.97 PF 1 1200.00 0.00 4.03 4.12 0.000322 2.49 482.18 119.92 0.22 SoquelCreekUP 203.28 PF 1 1200.00 0.00 4.03 4.12 0.000318 2.47 485.48 120.80 0.22 SoquelCreekUP 195.4 PF 1 1200.00 0.00 4.02 1.45 4.12 0.000304 2.47 486.29 121.46 0.22 SoquelCreekUP 170.36 Bridge
SoquelCreekUP 145.32 PF 1 1200.00 0.00 4.01 4.10 0.000294 2.38 505.04 126.03 0.21 SoquelCreekUP 140.31 PF 1 1200.00 0.00 4.01 4.10 0.000305 2.42 496.53 124.07 0.21 SoquelCreekUP 130.3 PF 1 1200.00 0.00 4.00 4.09 0.000324 2.48 483.37 121.08 0.22 SoquelCreekUP 120.28 PF 1 1200.00 0.00 3.99 4.09 0.000344 2.55 470.22 118.09 0.23 SoquelCreekUP 110.27 PF 1 1200.00 0.00 3.98 4.08 0.000366 2.62 457.24 115.10 0.23 SoquelCreekUP 103.87 PF 1 1200.00 0.00 3.97 4.08 0.000387 2.69 445.35 112.37 0.24 SoquelCreekUP 86.16 PF 1 1200.00 0.00 3.99 4.07 0.000266 2.26 531.51 133.52 0.20 SoquelCreekUP 76.02 PF 1 1200.00 0.00 4.00 4.06 0.000196 1.95 616.19 154.32 0.17 SoquelCreekUP 65.88 PF 1 1200.00 0.00 4.00 4.05 0.000161 1.77 677.47 169.42 0.16 SoquelCreekUP 59.74 PF 1 1200.00 0.00 4.00 4.05 0.000147 1.70 707.58 176.85 0.15 SoquelCreekUP 49.6 PF 1 1200.00 0.00 4.01 4.05 0.000131 1.61 747.58 186.74 0.14 SoquelCreekUP 38.98 PF 1 1200.00 0.00 4.01 4.04 0.000116 1.51 794.27 198.32 0.13 SoquelCreekUP 28.98 PF 1 1200.00 0.00 4.01 4.04 0.000107 1.46 824.57 206.33 0.13 SoquelCreekUP 18.98 PF 1 1200.00 0.00 4.01 4.04 0.000117 1.49 804.02 206.12 0.13 SoquelCreekUP 10 PF 1 1200.00 0.00 4.00 4.04 0.000123 1.52 791.15 206.16 0.14 SoquelCreekUP 0 PF 1 1200.00 0.00 4.00 1.32 4.04 0.000138 1.57 766.39 209.47 0.14 Alternative 5
Q1200
301
Item 9 A.
HEC-RAS Plan: Opt5QS17500 River: SoquelCreek Reach: SoquelCreekUP Profile: PF 1 Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
SoquelCreekUP 457.43 PF 1 17500.00 0.00 13.13 15.00 0.001634 11.32 1836.27 283.91 0.57 SoquelCreekUP 447.43 PF 1 17500.00 0.00 13.09 14.98 0.001679 11.39 1817.73 282.83 0.58 SoquelCreekUP 433.47 PF 1 17500.00 0.00 13.11 14.94 0.001713 11.17 1830.46 287.45 0.58 SoquelCreekUP 423.47 PF 1 17500.00 0.00 13.09 14.92 0.001725 11.15 1821.71 285.66 0.58 SoquelCreekUP 413.47 PF 1 17500.00 0.00 12.87 14.89 0.001762 11.71 1769.96 287.16 0.58 SoquelCreekUP 393.46 PF 1 17500.00 0.00 12.97 14.79 0.001780 11.05 1794.74 292.15 0.58 SoquelCreekUP 373.46 PF 1 17500.00 0.00 12.70 14.73 0.001920 11.59 1694.13 294.87 0.60 SoquelCreekUP 353.46 PF 1 17500.00 0.00 12.52 9.23 14.68 0.001986 11.92 1622.94 290.55 0.62 SoquelCreekUP 333.46 PF 1 17500.00 0.00 12.50 9.15 14.63 0.001981 11.82 1619.37 289.58 0.62 SoquelCreekUP 313.46 PF 1 17500.00 0.00 12.33 9.10 14.58 0.001999 12.09 1536.21 254.15 0.62 SoquelCreekUP 293.46 PF 1 17500.00 0.00 12.34 14.52 0.001936 11.86 1532.54 200.49 0.62 SoquelCreekUP 273.46 PF 1 17500.00 0.00 12.31 14.47 0.001912 11.82 1532.60 184.58 0.61 SoquelCreekUP 253.46 PF 1 17500.00 0.00 12.41 14.37 0.002435 11.24 1556.87 179.15 0.67 SoquelCreekUP 245.93 PF 1 17500.00 0.00 12.40 14.34 0.002365 11.19 1563.72 177.11 0.66 SoquelCreekUP 228.95 PF 1 17500.00 0.00 12.32 14.31 0.002315 11.29 1549.77 169.75 0.66 SoquelCreekUP 218.85 PF 1 17500.00 0.00 12.20 14.27 0.002117 11.54 1520.05 161.74 0.64 SoquelCreekUP 211.97 PF 1 17500.00 0.00 12.20 14.26 0.002138 11.52 1519.73 150.45 0.64 SoquelCreekUP 203.28 PF 1 17500.00 0.00 12.14 14.23 0.002074 11.61 1507.90 143.18 0.63 SoquelCreekUP 195.4 PF 1 17500.00 0.00 12.08 8.71 14.21 0.001841 11.71 1494.36 143.82 0.62 SoquelCreekUP 170.36 Bridge
SoquelCreekUP 145.32 PF 1 17500.00 0.00 11.89 13.93 0.001851 11.45 1528.91 148.64 0.60 SoquelCreekUP 140.31 PF 1 17500.00 0.00 11.87 13.92 0.002036 11.47 1525.11 143.71 0.62 SoquelCreekUP 130.3 PF 1 17500.00 0.00 11.45 13.80 0.002425 12.31 1421.37 137.80 0.68 SoquelCreekUP 120.28 PF 1 17500.00 0.00 10.98 13.67 0.002923 13.16 1331.51 137.93 0.74 SoquelCreekUP 110.27 PF 1 17500.00 0.00 10.88 9.27 13.64 0.003633 13.34 1312.21 156.21 0.81 SoquelCreekUP 103.87 PF 1 17500.00 0.00 9.62 9.62 13.50 0.005676 15.80 1111.51 147.73 1.00 SoquelCreekUP 86.16 PF 1 17500.00 0.00 8.15 8.15 12.16 0.005653 16.06 1090.40 139.30 1.00 SoquelCreekUP 76.02 PF 1 17500.00 0.00 7.37 7.37 11.05 0.005689 15.38 1137.69 154.86 1.00 SoquelCreekUP 65.88 PF 1 17500.00 0.00 6.92 6.92 10.38 0.005723 14.92 1173.01 169.85 1.00 SoquelCreekUP 59.74 PF 1 17500.00 0.00 6.73 6.73 10.09 0.005734 14.70 1190.18 177.25 1.00 SoquelCreekUP 49.6 PF 1 17500.00 0.00 6.97 6.49 9.78 0.004561 13.44 1302.23 187.14 0.90 SoquelCreekUP 38.98 PF 1 17500.00 0.00 7.30 9.57 0.003460 12.08 1448.60 198.82 0.79 SoquelCreekUP 28.98 PF 1 17500.00 0.00 7.44 9.46 0.003134 11.41 1533.92 206.96 0.74 SoquelCreekUP 18.98 PF 1 17500.00 0.00 7.23 9.41 0.003478 11.86 1475.24 211.82 0.79 SoquelCreekUP 10 PF 1 17500.00 0.00 7.16 6.26 9.38 0.003730 11.96 1462.96 219.52 0.82 SoquelCreekUP 0 PF 1 17500.00 0.00 6.41 6.41 9.27 0.005792 13.56 1290.64 226.00 1.00 Alternative 5
Q17500
302
Item 9 A.
Attachment 2
HEC-RAS Model Cross Section Plots
303
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 35
ExCond Plan: ExCondSteadFlowQ1200 6/27/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Crit PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Existing Conditions Q1200
304
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 35
ExCond Plan: ExCondSteadFlowQ1200 6/27/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Crit PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Existing Conditions Q1200
305
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 ExCond Plan: ExCondSteadFlowQ1200 6/27/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Existing Conditions Q1200
306
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 35
ExCond Plan: ExCondSteadFlow 6/27/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Crit PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Existing Conditions Q17500
307
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 35
ExCond Plan: ExCondSteadFlow 6/27/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Crit PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Existing Conditions Q17500
308
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 ExCond Plan: ExCondSteadFlow 6/27/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Existing Conditions Q17500
309
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 35
ExCondNoDebrisPier Plan: ExConQ17500SNoDebris 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Crit PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Existing Conditions - No Debris
310
Item 9 A.
0 100 200 300 400 500 600
0 5
10 15
20 25
30 35
ProCondOp1 Plan: SteadQP17500 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Bank Sta
.036 .026 .036
Alternative 1
311
Item 9 A.
0 100 200 300 400 500 600
0 5
10 15
20 25
30 35
ProCondOp1 Plan: SteadQP17500 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Bank Sta
.036 .026 .036
Alternative 1
312
Item 9 A.
0 100 200 300 400 500 600
0 5
10 15
20 25
30 35
ProCondOp1 Plan: SteadQP17500 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Alternative 1
313
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 35
ProCondOp1 Plan: SteadQP17500 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Crit PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Alternative 1
314
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 35
ProCondOp1 Plan: SteadQP17500 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Crit PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Alternative 1
315
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 ProCondOp1 Plan: SteadQP17500 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Alternative 1
316
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 35
ProCondOp1 Plan: Opt1Q1200Stead 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Crit PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Alternative 1
317
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 35
ProCondOp1 Plan: Opt1Q1200Stead 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Crit PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Alternative 1
318
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 ProCondOp1 Plan: Opt1Q1200Stead 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Alternative 1
319
Item 9 A.
0 100 200 300 400 500 600
0 5
10 15
20 25
30 35
ProCondOp1 Plan: Opt1Q1200Stead 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Bank Sta
.036 .026 .036
Alternative 1
320
Item 9 A.
0 100 200 300 400 500 600
0 5
10 15
20 25
30 35
ProCondOp1 Plan: Opt1Q1200Stead 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Bank Sta
.036 .026 .036
Alternative 1
321
Item 9 A.
0 100 200 300 400 500 600
0 5
10 15
20 25
30 35
ProCondOp1 Plan: Opt1Q1200Stead 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Alternative 1
322
Item 9 A.
0 100 200 300 400 500 600
0 5
10 15
20 25
30 35
40 ProCondOp2 Plan: Opt2QS17000 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Bank Sta
.036 .026 .036
Alternative 2
323
Item 9 A.
0 100 200 300 400 500 600
0 5
10 15
20 25
30 35
ProCondOp2 Plan: Opt2QS17000 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Bank Sta
.036 .026 .036
Alternative 2
324
Item 9 A.
0 100 200 300 400 500 600
0 5
10 15
20 25
30 35
ProCondOp2 Plan: Opt2QS17000 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Crit PF 1
Ground
Bank Sta
.036 .026 .036
Alternative 2
325
Item 9 A.
0 100 200 300 400 500 600
0 20
40 60
80 100
ProCondOp2 Plan: Opt2QS17000 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Crit PF 1
Ground
Bank Sta
Pier Debris
.036 .026 .036
Alternative 2
326
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 35
ProCondOp2 Plan: Opt2QS17000 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Alternative 2
327
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 35
ProCondOp2 Plan: Opt2QS17000 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Alternative 2
328
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 35
ProCondOp2 Plan: Opt2QS17000 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Crit PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Alternative 2
329
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 35
ProCondOp2 Plan: Opt2QS17000 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Crit PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Alternative 2
330
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 ProCondOp2 Plan: Opt2QS17000 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Alternative 2
331
Item 9 A.
0 100 200 300 400 500
0 5
10 15
20 25
30 ProCondOp2 Plan: Opt2QS17000 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Ground
Ineff
Bank Sta
.036 .026 .036
Alternative 2
332
Item 9 A.
0 100 200 300 400 500 600
0 5
10 15
20 25
30 35
ProCondOp2 Plan: Opt2QS1200 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Crit PF 1
Ground
Bank Sta
.036 .026 .036
Alternative 2
333
Item 9 A.
0 100 200 300 400 500 600
0 20
40 60
80 100
ProCondOp2 Plan: Opt2QS1200 6/28/2024
Station (ft) Elevation (ft)
Legend
EG PF 1
WS PF 1
Crit PF 1
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Stockton Avenue Bridge – Bridge Pier Debris Mitigation Feasibility Report CSWST2 |
Appendix C – Geotechnical Assessment of Debris Control Countermeasure Alternatives 379
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GEOTECHNICAL
ENVIRONMENTAL
WATER RESOURCES
CONSTRUCTION SERVICES
COASTAL/MARINE GEOTECHNICS
2350 Mission College Boulevard, Suite 800, Santa Clara, CA 95054 (408) 574-4900 Fax (888) 279-2698 www.engeo.com
Project No.
May 15, 2024 24335.000.002
Ms. Julia Harberson, PE, LEED AP, QSD
CSW/Stuber-Stroeh Engineering Group, Inc.
504 Redwood Boulevard, Suite 310
Novato, CA 94947
Subject: Stockton Avenue Bridge
Capitola, California
GEOTECHNICAL ASSESSMENT OF DEBRIS CONTROL
COUNTERMEASURE ALTERNATIVES
References: 1. Caltrans. 2022. Bridge Inspection Report, Routine Inspection, Bridge No. 36C0110, Soquel Creek. May 18, 2022.
2. Kimley Horn. 2016. Memorandum – Due Diligence, Stockton Avenue Bridge, City of Capitola, California. December 5, 2016.
3. Santa Cruz County. Plans – Capitola Bridge over Soquel Creek at Capitola.
October 23, 1933.
Dear Ms. Harberson:
As requested, we reviewed the geotechnical aspects of the debris countermeasure alternatives proposed for the existing Stockton Bridge located in Capitola, California. We performed a site reconnaissance on March 17, 2024.
Stockton Avenue Bridge crosses Soquel Creek and consists of two vehicular lanes and sidewalks on either side. The bridge was constructed in 1934 and consists of two abutments and three spans between 25 and 90 feet long. Based on bridge plans prepared by Santa Cruz County dated October 23, 1933, the abutments and in-creek piers are supported by 12-inch-diameter timber piles, noted as “25’+ long.”
Kimley Horn prepared a memorandum, dated December 15, 2016, outlining the flooding problems and debris concerns of Soquel Creek. The Stockton Avenue Bridge is the furthest downstream bridge in the watershed. The watershed is known to have large woody debris that has historically caused flooding by damming up bridges. Upstream bridges at Soquel Drive and Highway 1 have larger spans than the Stockton Avenue Bridge. This creates the potential for debris to accumulate upstream of Stockton Avenue Bridge.
Kimley Horn provided the following debris control countermeasures. • Debris Sweeper
• Debris Fins
• Debris Deflectors
• Bridge Replacement
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CSW/Stuber-Stroeh Engineering Group, Inc. 24335.000.002 Stockton Avenue Bridge May 15, 2024
GEOTECHNICAL ASSESSMENT OF DEBRIS CONTROL Page 2
COUNTERMEASURE ALTERNATIVES
From a geotechnical perspective, the debris sweeper, debris fin, and debris deflectors do not impact the geotechnical capacity of the existing bridge. If a bridge replacement is elected, a foundation exploration, in accordance with Caltrans, shall be performed.
If you have any questions regarding this letter, please contact us.
Sincerely,
ENGEO Incorporated
Jeanine T. Ruffoni, PE, GE Robert H. Boeche, CEG
jtr/rhb/cb
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Stockton Avenue Bridge – Bridge Pier Debris Mitigation Feasibility Report CSWST2 |
Appendix D – Stockton Avenue Bridge Mitigation Project
– Biological Constraints Analysis
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DENISE DUFFY & ASSOCIATES, INC.
PLANNING AND ENVIRONMENTAL CONSULTING
MEMORANDUM
Date: June 7, 2024
To: Julia Harberson, PE – CSW/Stuber-Stroeh Engineering Group, Inc.
From: Matthew Johnson - Senior Environmental Scientist/Project Manager, DD&A, Inc.
Subject: Stockton Avenue Bridge Mitigation Project – Biological Constraints Analysis This Biological Constraints Analysis provides the results of a biological analysis conducted for the Stockton Avenue Bridge Mitigation Project (project), located in the City of Capitola, California (Attachment A - Figure 1). The Capitola Village, a cultural and business center in Capitola, is located at the terminus of Soquel Creek, where it enters the Pacific Ocean.
The purpose of this memo is to assess the environmental conditions within and immediately adjacent to each alternative, evaluate the general habitat features present; assess the potential for sensitive habitats, including wetlands and waters of US/State, and special-status plant and wildlife species at the sites; evaluate environmental constraints at the site and within the local vicinity; and identify typical mitigation measures to address impacts and potential regulatory permit requirements. The survey area consists of the impact area shown on project plans (Attachment A – Figure 2). The alternatives discussed in this memo are as follows:
Alternative 1 - Angle Fin:
Angle eastern-most fin to minimize debris catch between pier and creek wall.
Alternative 2 - Debris Deflector Cage:
Install deflector cage to minimize debris catch.
Alternative 3 - Galvanized Pier Poles:
Install pier poles to minimize debris catch.
Alternative 4 - Manufactured Floating Debris Sweeper:
Install manufactured floating debris sweeper to minimize debris catch.
Alternative 5 – Clear Span Bridge:
Remove existing footings within the channel of Soquel Creek to support a clear span bridge and widen bridge by 8’.
METHODS
DD&A Environmental Scientists conducted reconnaissance-level surveys of the survey area on May 14, 2024, to identify any special-status plant or wildlife species or suitable habitat for these species and identify any sensitive habitats present within the site. Survey methods included walking the survey area using aerial maps and GPS to map biological resources. Available reference materials were reviewed prior to 383
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conducting the field survey (see “Data Sources” below). Data collected during the survey were used to assess the environmental conditions of the survey area and its surroundings, evaluate environmental constraints at the site and within the local vicinity, and provide a basis for recommendations to minimize and avoid impacts.
The survey area was surveyed for botanical resources following the applicable guidelines outlined in the U.S. Fish and Wildlife Service (USFWS) Guidelines for Conducting and Reporting Botanical Inventories for Federally listed, Proposed and Candidate Plants (USFWS, 2000), the CDFW Protocols for Surveying and Evaluating Impacts to Special Status Native Plant Populations and Natural Communities (CDFW, 2018), and the California Native Plant Society (CNPS) Botanical Survey Guidelines (CNPS, 2001).
The survey also included an assessment of potentially jurisdictional wetlands and waters within the survey area in accordance with the requirements set forth in The Field Guide for Wetland Delineation: 1987 Corps of Engineers Manual (Wetland Training Institute, 1995) and the Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Arid West Region (Version 2.0) (Army Corps of Engineers [ACOE], 2008).
Data Sources
The primary literature and data sources reviewed to determine the occurrence or potential for occurrence of special-status species within and adjacent to the survey area include:
• Current agency status information from the USFWS and CDFW for species listed, proposed for listing, or candidates for listing as Threatened or Endangered under the ESA or CESA, and those considered CDFW “species of special concern” (CDFW, 2024b); • CDFW’s California Natural Diversity Database (CNDDB) occurrence reports for the Mt. Carmel quadrangle and the eight surrounding quadrangles (Monterey, Seaside, Spreckels, Soberanes Point, Carmel Valley, Point Sur, Big Sur, and Ventana Cones) (CDFW, 2024c; Attachment B); • The USFWS’s Information for Planning and Consulting (IPaC) Resource List (USFWS, 2024a:
Attachment B); and
• The CNPS Inventory of Rare and Endangered Vascular Plants of California (CNPS, 2024).
From these resources, a list of special-status plant and wildlife species known or with the potential to occur within and adjacent to the survey area was created (Attachment C). The list presents these species along with their legal status, habitat requirements, and a brief statement of their likelihood to occur.
Botany
A Manual of California Vegetation (Sawyer et.al., 2009) was utilized to determine if vegetation types identified as sensitive on CDFW’s California Natural Communities List (CDFW, 2024a) were present within the survey area. Scientific nomenclature for plant species identified within this document follows The Jepson Manual: Vascular Plants of California, Edition 2 (Baldwin et al., 2012); common names follow The Plants of Monterey County: An Illustrated Field Key (Matthews and Mitchell, 2015).
Wildlife
The wildlife literature and data sources were reviewed include CDFW reports on special-status wildlife (Remsen, 1978; Williams, 1986; Jennings and Hayes, 1994; Thelander, 1994), California Wildlife Habitat Relationships Program species-habitat models (Zeiner et al., 1988; and Zeiner et al., 1990), and general wildlife references (Stebbins, 1972, 1985, and 2003).
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Special-Status Species
Special-status species are those plants and animals that have been formally listed or proposed for listing as Endangered or Threatened or are Candidates for such listing under ESA or CESA. Listed species are afforded legal protection under the ESA and CESA. Species that meet the definition of rare or endangered under the CEQA Section 15380 are also considered special-status species. Animals identified as “species of special concern” (most of which are species whose breeding populations in California may face extirpation if current population trends continue) on the CDFW’s “Special Animals” list (CDFW, 2024b) meet this definition and are typically provided management consideration through the CEQA process, although they are not legally protected under the ESA or CESA.
Plants listed as rare under the California Native Plant Protection Act (CNPPA) or included in CNPS California Rare Plant Ranks (CRPR; formerly known as CNPS Lists) 1A, 1B, 2A, and 2B are also treated as special-status species as they meet the definitions of Sections 2062 and 2067 of the CESA and in accordance with CEQA Guidelines Section 15380. In general, CDFW requires that plant species on CRPR 1A (Plants presumed extirpated in California and Either Rare or Extinct Elsewhere), CRPR 1B (Plants rare, threatened, or endangered in California and elsewhere), CRPR 2A (Plants presumed extirpated in California, but more common elsewhere), and CRPR 2B (Plants rare, threatened, or endangered in California, but more common elsewhere) of the CNPS Inventory of Rare and Endangered Vascular Plants of California (CNPS, 2024) be fully considered during the preparation of environmental documents relating to CEQA.1 In addition, species of vascular plants, bryophytes, and lichens listed as having special-status by the CDFW are considered special-status plant species (CDFW, 2024c).
Raptors (e.g., eagles, hawks, and owls) and their nests are protected in California under Fish and Game Code Section 3503.5. Section 3503.5 states that it is “unlawful to take, possess, or destroy the nest or eggs of any such bird except otherwise provided by this code or any regulation adopted pursuant thereto.” In addition, fully protected species under the Fish and Game Code Section 3511 (birds), Section 4700 (mammals), Section 5515 (fish), and Section 5050 (reptiles and amphibians) are also considered specialstatus animal species. Species with no formal special-status designation but thought by experts to be rare or in serious decline may also be considered special-status animal species in some cases, depending on project-specific analysis and relevant, localized conservation needs or precedence.
Sensitive Habitats
Sensitive habitats include riparian corridors, wetlands, habitats for legally protected species, areas of high biological diversity, areas supporting rare or special-status wildlife habitat, and unusual or regionally restricted habitat types. Vegetation types considered sensitive include those identified as sensitive on the CDFW’s California Natural Communities List (i.e., those habitats that are rare or endangered within the borders of California) (CDFW, 2024a) and those that are occupied by species listed under ESA or are critical habitat in accordance with ESA. Specific habitats may also be identified as sensitive in city or county general plans or ordinances. Sensitive habitats are regulated under federal regulations (such as the Clean Water Act [CWA] and Executive Order 11990 – Protection of Wetlands), state regulations (such as CEQA and the CDFW Streambed Alteration Program), or local ordinances or policies (such as city or county tree ordinances and general plan policies).
1 Species on CRPR 3 (Plants about which we need more information - a review list) and CRPR 4 (Plants of limited distribution - a watch list) may, but generally do not, meet the definitions of Sections 2062 and 2067 of CESA, and are not typically considered in environmental documents relating to CEQA. 385
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SURVEY RESULTS
Habitat Types
As described in the Methods section, habitat types were identified within the survey area. Habitat types identified include developed and riverine (Attachment A – Figure 3). The discussion below provides an overview of the habitats observed within and adjacent to the project area and identifies if sensitive habitats are present or potentially present. Additional discussion of sensitive habitats is provided below.
Developed
• A Manual of California Vegetation classification(s): None • California Natural Communities List: Not listed
Developed portions of the survey area include the footprint of the existing bridge and surrounding urban infrastructure including sidewalks (Attachment A – Figure 3). Developed areas provide only low-quality habitat for plants and wildlife. Common wildlife species which do well in developed areas include American crow (Corvus brachyrhynchos), raccoon (Procyon lotor), striped skunk (Mephitis mephitis), scrub jay (Aphelocoma californica), European starling (Sturnus vulgaris), western fence lizard (Sceloporus occidentalis), and rock dove (Columba livia). No special-status wildlife species were observed within the developed areas of the survey area, and none are expected to occur. However, multiple active and historic violet-green swallow (Tachycineta thalassina) nests were observed underneath the existing bridge.
Riverine
• A Manual of California Vegetation classification(s): None • California Natural Communities List: Not listed
Riverine habitats are distinguished by intermittent or continuously running surface water (Zeiner et al., 1988). A stream typically originates at an elevated source, such as a spring or lake, and flows downward at a rate relative to slope or gradient and the volume of surface runoff. Riverine areas provide habitat for many aquatic species. The majority of inhabitants of fast-moving streams live in riffles on the underside of rubble and gravel, including mayflies and caddisflies. In slower moving waters with accumulating sediment, typical organisms include various species of mollusks and crustaceans.
Soquel Creek is known to support populations of central California coast steelhead (Oncorhynchus mykiss irideus), tidewater goby (Eucyclogobius newberryi), and western pond turtle (Actinemys marmorata), as well as a variety of avian species which forage within the creek. Additionally, Soquel Creek is a navigable water and is considered waters of the U.S. and State.
Sensitive Habitats
Waters of the US/State
Jurisdictional waters of the U.S. and State were identified within the survey area, consisting of open water of Soquel Creek (i.e., riverine habitat), a navigable waterway (ACOE 1971). The ordinary high-water mark (OHWM) defines the lateral extent of nontidal aquatic features in the absence of adjacent wetlands in the United States. The federal regulatory definition of the OHWM, 33 CFR 328.3(c)(7), states the OHWM is “that line on the shore established by the fluctuations of water and indicated by physical characteristics such as [a] clear, natural line impressed on the bank, shelving, changes in the character of soil, destruction of 386
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terrestrial vegetation, the presence of litter and debris, or other appropriate means that consider the characteristics of the surrounding areas.”
During the May 14, 2024, reconnaissance survey, DD&A documented the OHWM indicated by a stain line on the bridge piers and the confined banks of Soquel Creek (Attachment D – Photos 1-3) (Attachment A – Figure 4). Within the survey area Soquel Creek is a confined channel within engineered banks. The OHWM is approximately 11 feet 7 inches from the deck of the existing bridge and approximately 3 feet 8 inches from the bottom of Soquel Creek.
Special-Status Wildlife Species
The following discussion summarizes the special-status wildlife species that are known or have a moderate to high potential to occur within the survey area. Each of these species’ known or potential presence within the survey area are discussed below, as well as mitigation measures to reduce potential impacts to a lessthan-significant level under CEQA. No other special-status wildlife species are expected to occur based on lack of suitable habitat. Please refer to Attachment C for lists of all species evaluated for potential to occur.
Western Pond Turtle
Western pond turtle is proposed for listing as a federally endangered species and is a California Species of Special Concern. This species is uncommon to common in permanent or nearly permanent aquatic resources in a wide variety of habitats throughout California, west of the Sierra-Cascade crest and are absent from desert regions, except in the Mojave Desert along the Mojave River and its tributaries. Elevation range extends from near sea level to 1430 meters (4690 feet). Western pond turtles require basking sites such as partially submerged logs, rocks, mats of floating vegetation, or open mud banks. The home range of western pond turtles is typically quite restricted; however, ongoing research indicates that in many areas, turtles may leave the watercourse in late fall and move into upland habitats where they burrow into duff and/or soil and overwinter (Holland, 1994). However, western pond turtles remain active year-round and may move several times during the course of overwintering. The time spent in the terrestrial habitat appears highly variable; in southern California western pond turtles may remain in these sites for only a month or two.
In pond and lake habitats, however, some turtles remain in the pond during the winter (Holland, 1994).
Additionally, during the spring or early summer, females move overland for up to 100 meters (325 feet) to find suitable sites for egg-laying. Nests are typically excavated in compact, dry soils in areas characterized by sparse vegetation, usually short grasses or forbs (Holland, 1994). Three to 11 eggs are laid from March to August depending on local conditions (Ernst and Barbour, 1972). The western pond turtle is not known to be territorial, but aggressive encounters, including gesturing and physical combat (Bury and Wolfheim, 1973), are common and may function to maintain spacing on basking sites and to settle disputes over preferred spots. This species is considered omnivorous and food sources include aquatic plant material, beetles, and a wide variety of aquatic invertebrates. Fishes, frogs, and carrion have also been reported among their food (Stebbins, 1972).
Soquel Creek provides suitable aquatic habitat for this species. Additionally, suitable basking sites, including submerged logs, were observed within the survey area. The nearest CNDDB occurrence of this species is located approximately one mile upstream from the survey area in Soquel Creek. Therefore, this species has moderate potential to occur within the survey area. 387
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Central California Coast Steelhead
The central California coast steelhead is currently designated as federally Threatened in all naturally spawned populations (and their progeny) in streams from the Russian River (inclusive) to Aptos Creek (inclusive), and the drainages of San Francisco, San Pablo, and Suisun Bays eastward to Chipps Island at the confluence of the Sacramento and San Joaquin Rivers; and tributary streams to Suisun Marsh including Suisun Creek, Green Valley Creek, and an unnamed tributary to Cordelia Slough (commonly referred to as a Red Top Creek), exclusive of the Sacramento-San Joaquin River Basin of the California Central Valley (71 FR 833-862). The designation of critical habitat for steelhead became effective on January 2, 2006.
Primary constituent elements include freshwater spawning sites, freshwater rearing sites, freshwater migration corridors, estuarine areas, nearshore marine areas, and offshore areas.
The present distribution and abundance of steelhead in California has been greatly reduced from historical levels. In general, steelhead migrate to sea as two-year-old fish, spend two years in the ocean, and then return to fresh water to spawn. Peak spawning for steelhead occurs from December through April in small streams and tributaries. Unlike Pacific salmon, steelhead do not necessarily die after spawning, although repeat spawning rates are generally low and vary considerably among populations. Steelhead have traditionally been grouped into seasonal runs according to their peak migration period; in California there are well-defined winter, spring, and fall runs.
This species is known to occur within Soquel Creek; therefore, this species has a high potential to occur within the survey area.
Tidewater goby
The Tidewater goby is a federally Endangered species and a CDFW species of special concern. The tidewater goby is a small native goby found along the Pacific coast of California from the Smith River in Del Norte County, south to Agua Hedionda Lagoon in San Diego County. Local records for this species from the California Academy of Sciences show presence in the Paper Mill Creek and Rodeo Lagoon, the mouth of the Corte Madera Creek, in the vicinity of Lake Merced in San Francisco, and San Pablo Bay adjacent to the Sacramento-San Joaquin Estuary. Individuals of this species are in different developmental stages throughout the year. The spawning peak of this species in Rodeo Lagoon can be separated into two periods: from late March through July, and from late August through November. The male tidewater goby digs a vertical burrow approximately 100-200 mm into the sandy bottom in water 25-50 cm deep, which the male then guards after the female completes egg deposition. It has been reported that mollusks, insects, and crustaceans are the primary food for the tidewater goby.
This species is known to occur within Soquel Creek; therefore, this species has a high potential to occur within the survey area.
Nesting Avian Species
The California Fish and Game Code protects nesting birds, their eggs, and nests in several sections:
• Section 3503: Makes it illegal to take, possess, or destroy any bird's nest or eggs without reason. • Section 3503.5: Makes it illegal to take, possess, or destroy any bird of prey's nest or eggs, or the birds themselves.
• Section 3511: Protects 13 bird species that are fully protected. 388
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The nesting season varies by species and location, but for many birds in California, nesting season is typically from February to August. Nesting avian species that typically occur in the habitat type within and surrounding the survey area may include but is not limited to; cliff swallow (Petrochelidon pyrrhonota), dark-eyed junco (Junco hyemalis), Eurasian collared dove (Streptopelia decaocto), Anna’s hummingbird (Calypte anna), and house finch (Haemorhous mexicanus).
DD&A documented cliff swallow nests on the underside of Stockton Bridge during the May 14 reconnaissance survey (Attachment D – Photo 4) and several birds were observed foraging within and around Soquel Creek. Additionally, trees adjacent to Stockton Bridge may provide nesting habitat for several avian species.
Special-Status Plant Species
No special-status plant species were observed within the survey area during the survey or were determined unlikely to occur based on the species-specific reasons presented in Attachment C.
Potential Impacts and Typical Mitigation
Impact 1. Western pond turtle is known to occur within Soquel Creek and has a high potential to occur within the survey area. Construction-phase activities associated with the development of the project have the potential to impact (take) individual western pond turtles. This may include direct injury or mortality as a result of construction activities occurring within the channel of Soquel Creek. This is a potentially significant impact that can be reduced to a less than significant level with the implementation of the mitigation presented below.
Mitigation Measure 1a: Prior to construction activities, the project proponent shall retain a qualified biologist to conduct an Employee Education Program for the construction crew. The biologist shall meet with the construction crew at the project site at the onset of construction to educate the construction crew on the following: a) a review of the project boundaries; b) all special-status species that may be present, their habitat, and proper identification; c) the specific mitigation measures that will be incorporated into the construction effort; d) the general provisions and protections afforded by the regulatory agencies; and e) the proper procedures if a special-status animal is encountered within the project site.
Mitigation Measure 1b: To avoid or minimize impacts to western pond turtle, a qualified biologist shall conduct a pre-construction survey for western pond turtles and their nests within the project site no more than three days prior to construction. If a western pond turtle nest is found, it will be monitored and avoided until the eggs hatch. All western pond turtles discovered within the project site immediately prior to or during project activities shall be allowed to move out of the area of their own volition. If this is not feasible, they shall be captured by a qualified biologist and relocated out of harm's way to the nearest suitable habitat at least 100 feet upstream or downstream from the project site where the individual was found.
Impact 2. Central California coast steelhead and tidewater goby are known to occur within Soquel Creek and have a high potential to occur within the survey area. Construction-phase activities associated with the development of the project have the potential to impact (take) individuals of these species. This may include direct injury or mortality as a result of construction activities occurring within the channel of Soquel Creek.
This is a potentially significant impact that can be reduced to a less than significant level with the implementation of the mitigation presented below.
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Mitigation Measure 2a: The project proponent shall consult with the National Oceanic and Atmospheric Administration (NOAA) National Marine Fisheries Service (NMFS) to ensure compliance with ESA. ESA compliance may result in the need for incidental take coverage through Section 7 or Section 10 of the ESA. The resulting Biological Opinion (BO) and Incidental Take Statement may include typical conservation measures as described below in Mitigation Measures 2b-2g.
Mitigation Measure 2b: Project personnel shall ensure that trash and food items are contained in animal-proof containers and removed at least once a week to avoid attracting opportunistic predators such as coyotes. Plastic water bottles and plastic bags shall be picked up and removed daily even if not generated by on-site personnel.
Mitigation Measure 2c: The project shall utilize erosion control measures throughout all phases of the project where sediment runoff from exposed slopes could enter Soquel Creek.
Mitigation Measure 2d: Construction materials and/or equipment shall not be stockpiled or stored where they may be washed into Soquel Creek or cover adjacent riparian vegetation. Stockpiles shall be covered when measurable rain is forecasted.
Mitigation Measure 2e: All equipment that will be entering the project site shall be cleaned of materials deleterious to aquatic life including oil, grease, hydraulic fluid, soil, other debris and invasive species. Wash water containing mud or silt from washing or other operations shall not be allowed to enter Soquel Creek.
Mitigation Measure 2f: Qualified biologists with expertise in the areas of anadromous salmonid biology shall conduct fish relocation activities associated with construction, if determined necessary. Fish relocation shall be conducted in a manner which minimizes all potential risks to salmonids.
Fish relocation shall first use a seine net without a bag to herd fish out of the work site, if practicable, before capturing fish with other nets or using electrofishing techniques. Herding fish out of the work site with a seine will reduce the number of fish exposed to capture and electrofishing activities and reduce the number of fish subject to risks of mortality.
Salmonids shall be handled with extreme care and kept in water to the maximum extent possible during rescue activities. All captured fish must be kept in cool, shaded, and aerated water protected from excessive noise, jostling, or overcrowding. Fish shall not be held in buckets with potential predators. Fish will not be removed from this water except when released. Captured salmonids will be relocated as soon as possible to an instream location in which suitable habitat conditions are present to allow for adequate survival for transported fish and fish already present.
Mitigation Measure 2g: If any salmonids are found dead or injured, the biologist shall contact NMFS within 24-hours to review the activities resulting in the take and to determine if additional protective measures are required.
Impact 3. Several avian species have the potential to nest on Stockton Bridge and/or the trees adjacent to the bridge. Construction-phase activities associated with the development of the project have the potential to impact active nests either through direct impact (nest removal) or indirect impact (noise disturbance), resulting in nest abandonment or direct mortality. Impacts to active avian nests would be considered significant. This is a potentially significant impact that can be reduced to a less than significant level with the implementation of the mitigation presented below. 390
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Mitigation Measure 3: Construction activities that may directly (e.g., bridge removal) or indirectly affect (e.g., noise/ground disturbance) avian species nests shall be timed to avoid the nesting seasons (February 1 through September 15).
If construction activities must occur during the nesting season (February 1 through September 15), a qualified biologist shall conduct pre-construction surveys for nesting avian species within 500 feet of the proposed construction activities. Pre-construction surveys should be conducted no more than 7 days prior to the start of the construction activities during the early part of the breeding season (February through April) and no more than 14 days prior to the initiation of these activities during the late part of the breeding season (May through August).
If avian nests are identified during the pre-construction surveys, the qualified biologist would notify the contractor and an appropriate no-disturbance buffer would be imposed in which no construction activities or disturbance would take place (generally 500 feet in all directions for raptors; other avian species may have species-specific requirements) until the young of the year have fledged and are no longer reliant upon the nest or parental care for survival, as determined by a qualified biologist.
Once construction begins, the qualified biologist shall continuously monitor nests to detect behavioral changes resulting from the project. If behavioral changes resulting from the project occur, the no-disturbance buffer shall be increased.
Impact 4. Soquel Creek is a navigable waterway therefore it is considered waters of the US and the State. Additionally, Soquel Creek is subject to California Department of Fish and Wildlife (CDFW) jurisdiction under Section 1602 of CDFG code. Impacts associated with the installation of debris mitigation materials or with the removal of the existing bridge, to this sensitive habitat, would be considered significant. This is a potentially significant impact that can be reduced to a less than significant level with the implementation of the mitigation presented below.
Mitigation Measure 4: The project proponent shall coordinate with the ACOE, Regional Water Quality Control Board (RWQCB), and CDFW to procure a permit pursuant to the CWA Section 404, CWA Section 401, and CDFG Code Section 1602, respectively.
CONCLUSION & RECOMMENDATIONS
The discussion below provides a summary of the sensitive natural resources with the potential to occur within and adjacent to the survey area and regulatory permits that may be required if these resources are impacted. In addition, the summary below provides the main environmental concerns and permitting requirements for the alternatives considered.
Comparison of Project Alternatives
As described below, the similarity of the infrastructure proposed under Alternatives 1 through 5 would result in equal impacts to biological resources, regardless of which Alternative is implemented. Each Alternative would result in impacts to the three special-status species described above (western pond turtle, central California coast steelhead, and tidewater goby), as well as impacts to Waters of the U.S. and State.
Additionally, the survey area is located within the Coastal Zone and would result in impacts to the channel of Soquel Creek; therefore, the project is also under the jurisdiction of the California Coastal Commission and California Department of Fish and Wildlife. Impacts to these resources would likely require acquisition of the following regulatory permits:
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• United States Fish and Wildlife Service (USFWS) and National Marine Fisheries Service (NMFS): Section 7 of the Endangered Species Act (ESA).
• California Department of Fish and Wildlife (CDFW): Section 1602 of the California Fish and Game Code (Streambed Alteration Agreement).
• United States Army Corps of Engineers (ACOE): Section 404 of the Clean Water Act (CWA) and/or Rivers and Harbor Act Section 10 Permit.
• Central Coast Regional Water Quality Control Board (RWQCB): Section 401 of the CWA. • California Coastal Commission: Coastal Development Permit.
Alternative 1: Angle Fin
Alternative 1 would include installing fins onto the existing abutments within the channel of Soquel Creek.
The eastern most fin would be installed at an angle to minimize debris catch between the pier and creek wall. This Alternative would include installation of eight reinforced concrete piers within the channel of Soquel Creek. Implementation of Alternative 1 would result in impacts to the three special-status species described above, as well as impacts to Waters of the U.S. and State. This would require acquisition of the regulatory permits outlined above.
Alternative 2: Debris Deflector Cage
Alternative 2 would include installing debris deflector cages onto the existing abutments within the channel of Soquel Creek. This Alternative would include installation of three reinforced concrete piers on each cage within the channel of Soquel Creek, for a total of six piers. Alternative 2 would result in impacts to the same resources described above; therefore, there are no significant differences in the biological impact between the Alternatives and the same regulatory permits would be required.
Alternative 3: Galvanized Pier Poles
Alternative 3 would include installing galvanized pier poles embedded in concrete piers onto the existing abutments within the channel of Soquel Creek. This Alternative would include installation of six reinforced concrete piers on each cage within the channel of Soquel Creek, for a total of 12 piers. Alternative 3 would result in impacts to the same resources described above; therefore, there are no significant differences in the biological impact between the Alternatives and the same regulatory permits would be required.
However, the increased number of piers proposed under Alternative 3 may result in increased mitigation required by the regulatory agencies.
Alternative 4: Manufactured Floating Debris Sweeper
Alternative 4 would include the installation of two manufactured floating debris sweepers adjacent to the existing abutments within the channel of Soquel Creek. The sweepers would require one reinforced concrete pier each, for a total of two piers. The sweepers would rise and fall with the water level of the creek.
Alternative 4 would result in impacts to the same resources described above; therefore, there are no significant differences in the biological impact between the Alternatives and the same regulatory permits would be required. However, the decreased number of piers proposed under Alternative 4 may result in decreased mitigation required by the regulatory agencies.
Alternative 5: Clear Span Bridge
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Alternative 5 would include widening the bridge by 8 feet to accommodate an 8’ sidewalk, 5’ bike lane, and 12’ vehicle travel lane on each side, for a total width of 52 feet. The existing piers would be removed from the channel of Soquel Creek to support a clear span bridge. The existing timber piles will remain in place and the pier footings may remain in place; however, this will be determined at a later date. Alternative 5 would result in impacts to the same resources described above; therefore, the same regulatory permits would be required. However, no new impacts to the channel of Soquel Creek are proposed under this Alternative and existing structures within the channel are proposed for removal. Therefore, this Alternative may result in reduced mitigation requirements from the regulatory agencies.
Conclusion
Each proposed Alternative has the potential to impact federal and state-listed wildlife species and are likely to require acquisition of state and federal ITPs. Additionally, all Alternatives will impact Waters of the U.S. and/or State which will likely require acquisition of regulatory permits from the ACOE and RWQCB.
Additionally, the project is also under the jurisdiction of the California Coastal Commission and CDFW.
As identified above, the infrastructure proposed for Alternatives 1 through 5 are very similar and would result in almost identical impacts to the sensitive resources described in this report. For this reason, the environmental impact of Alternatives 1 through 5 would generally be the same. Therefore, due to the similarity of the proposed Alternatives, there is no preferred Alternative from a biological perspective.
However, the information outlined above regarding potential mitigation requirements from the regulatory agencies may be taken into account when choosing a project Alternative. 393
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References
Baldwin, B. G, et. al. 2012. The Jepson Manual – Vascular Plants of California, Second Edition, Thoroughly Revised and Expanded. University of California Press. Berkeley, CA. 1600 pp.
CDFW. 2018. Protocols for Surveying and Evaluating Impacts to Special Status Native Plant Populations and Natural Communities.
[CDFW] California Department of Fish and Game. 2024a. Natural Communities List. Available Online at: https://wildlife.ca.gov/Data/VegCAMP/Natural-Communities CDFW. 2024b. Special Animals List. Available online at
https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=109406 CDFW. 2024c. California Natural Diversity Database Rare Find 5 Report. Accessed April 2024.
California Native Plant Society (CNPS). 2001. Botanical Survey Guidelines.
CNPS. 2024. Inventory of Rare and Endangered Plants (online inventory, v8-03). California Native Plant Society. Sacramento, CA. Available online at: http://www.rareplants.cnps.org/ Ernst, C. H., and R. W. Barbour. 1972. Turtles of the United States. Univ. Kentucky Press, Lexington. 347pp.
Google LLC. 2023. Google Earth Pro Aerial Imagery.
Holland. 1994. The Western Pond Turtle; Habitat and History, 1993-1994 Final Report. Oregon Dept. of Fish and Wildlife, Portland, OR.
Jennings, M.R. and M.P. Hayes. 1994. Amphibian and reptile species of special concern in California. Final report to the California Department of Fish and Game, Inland Fisheries Division. 255 pp.
Matthews, M.A and M. Mitchell. 2015. The Plants of Monterey County; an Illustrated Field Key (Second Edition). California Native Plant Society, Sacramento, California. 446 pp.
Remsen, J.V. Jr. 1978. Bird species of special concern in California. California Dept. of Fish and Game, Nongame Wildlife Investigations, Wildlife Management Branch Administrative Report No. 78-1.
Sawyer, J.O., T. Keeler-Wolf, and J.M. Evens. 2009. A manual of California vegetation 2nd Edition.
California Native Plant Society, Sacramento, CA. 1300 pp.
Stebbins, R.C. 1972. California Amphibians and Reptiles. University of California Press, Berkeley, CA. 152 pp.
Stebbins, R.C. 1985. Western reptiles and amphibians. Houghton Mifflin Company, Boston, MA. 336 pp Stebbins, R.C. 2003.Western reptiles and amphibians, 3rd edition. Houghton Mifflin Company, New York, NY.533 p
Thelander, C. (ed.). 1994. Life on the edge: A guide to California’s endangered natural resources:
wildlife. BioSystems Books, Santa Cruz, CA.
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U.S. Army Corps of Engineers (ACOE). 1971. Navigable Waterways within the San Francisco District of the Army Corps of Engineers. Found Online at:
https://www.spn.usace.army.mil/Portals/68/docs/regulatory/1%20-%20Sect10waters.pdf ACOE. 2008. Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Arid West Region (Version 2.0). Ed. J.S. Wakeley, R.W. Lichvar, and C.V. Noble. ERDC/EL TR-08-28.
Vicksburg, MS: U.S. Army Engineer Research and Development Center. 123 pp. [USGS] U.S. Geologic Survey. 2023. National Hydrography Dataset. Available online at:
https://www.usgs.gov/programs/national-geospatial-program/national-map [USDA-NRCS] U.S. Department of Agriculture – Natural Resources Conservation Service. 2019. Web Soil Survey. Available online at: https://websoilsurvey.nrcs.usda.gov/app/ USFWS. 2000. Guidelines for Conducting and Reporting Botanical Inventories for Federally Listed, Proposed, and Candidate Plants.
[USFWS] U.S. Fish and Wildlife Service. 2024a. Information Planning and Consultation Reports.
Accessed September 2023.
USFWS. 2023b. National Wetlands Inventory. Available online at:
https://www.fws.gov/program/national-wetlands-inventory/wetlands-mapper Wetland Training Institute, Inc. 1995. Field Guide for Wetland Delineation: 1987 Corps of Engineers Manual. Glenwood, NM. WTI 02-1. 143 pp.
Williams, D. 1986. Mammalian species of special concern in California. California Department of Fish and Game Report 86-1. 112 pp.
Williams, P., R. Thorp, L. Richardson, and S. Colla. 2014. Bumble Bees of North America: An Identification Guide. Princeton University Press, Princeton, New Jersey. 209 pp.
Zeiner, D. C., W. F. Laudenslayer, Jr., K. E. Mayer, and M. White (eds.). 1988. California’s wildlife, Volume I: Amphibians and reptiles. California Department of Fish and Game, Sacramento, CA. 272 pp.
Zeiner, D. C., W. F. Laudenslayer, Jr., K. E. Mayer, and M. White (eds.). 1990. California’s Wildlife, Volume II: Birds. California Department of Fish and Game, Sacramento, CA.731 pp.
Attachments
Attachment A: Figures 1-4
Attachment B: CNDDB and IPaC
Attachment C: Special-Status Species Table
Attachment D: Site Photos
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Attachment A: Figures 1-4
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Project Location 1
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Survey Area 2
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Vegetation Types 3
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Waters of the U.S. and/or State 4
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Attachment B: CNDDB and IPaC
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Species Element Code Federal Status State Status Global Rank State Rank Rare Plant
Rank/CDFW
SSC or FP
Accipiter cooperii
Cooper's hawk
ABNKC12040 None None G5 S4 WL
Adela oplerella
Opler's longhorn moth
IILEE0G040 None None G2 S2
Agelaius tricolor
tricolored blackbird
ABPBXB0020 None Threatened G1G2 S2 SSC
Agrostis blasdalei
Blasdale's bent grass
PMPOA04060 None None G2G3 S2 1B.2
Ambystoma californiense pop. 1
California tiger salamander - central California DPS
AAAAA01181 Threatened Threatened G2G3T3 S3 WL
Ambystoma macrodactylum croceum
Santa Cruz long-toed salamander
AAAAA01082 Endangered Endangered G5T1T2 S2 FP
Amsinckia lunaris
bent-flowered fiddleneck
PDBOR01070 None None G3 S3 1B.2
Aneides niger
Santa Cruz black salamander
AAAAD01070 None None G3 S3 SSC
Anniella pulchra
Northern California legless lizard
ARACC01020 None None G3 S2S3 SSC
Anomobryum julaceum
slender silver moss
NBMUS80010 None None G5? S2 4.2
Antrozous pallidus
pallid bat
AMACC10010 None None G4 S3 SSC
Aphyllon robbinsii
Robbins' broomrape
PDORO040Q0 None None G1 S1 1B.1
Aquila chrysaetos
golden eagle
ABNKC22010 None None G5 S3 FP
Arctostaphylos andersonii
Anderson's manzanita
PDERI04030 None None G2 S2 1B.2
Arctostaphylos hookeri ssp. hookeri
Hooker's manzanita
PDERI040J1 None None G3T2 S2 1B.2
Arctostaphylos pajaroensis
Pajaro manzanita
PDERI04100 None None G1 S1 1B.1
Arctostaphylos silvicola
Bonny Doon manzanita
PDERI041F0 None None G1 S1 1B.2
Ardea herodias
great blue heron
ABNGA04010 None None G5 S4
Arenaria paludicola
marsh sandwort
PDCAR040L0 Endangered Endangered G1 S1 1B.1
Quad<span style='color:Red'> IS </span>(Felton (3712211)<span style='color:Red'> OR </span>Laurel (3712118)<span style='color:Red'> OR </span>Loma Prieta (3712117)<span style='color:Red'> OR </span>Santa Cruz (3612281)<span style='color:Red'> OR </span>Soquel (3612188)<span style='color:Red'> OR </span>Watsonville West (3612187)) Query Criteria:
Report Printed on Friday, May 03, 2024
Commercial Version -- Dated March, 31 2024 -- Biogeographic Data Branch Page 1 of 6 Information Expires 9/30/2024
Selected Elements by Scientific Name
California Department of Fish and Wildlife
California Natural Diversity Database
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Species Element Code Federal Status State Status Global Rank State Rank Rare Plant
Rank/CDFW
SSC or FP
Astragalus agnicidus
Humboldt County milk-vetch
PDFAB0F080 None Endangered G2 S2 1B.1
Athene cunicularia
burrowing owl
ABNSB10010 None None G4 S2 SSC
Bombus caliginosus
obscure bumble bee
IIHYM24380 None None G2G3 S1S2
Bombus crotchii
Crotch's bumble bee
IIHYM24480 None Candidate
Endangered
G2 S2
Bombus occidentalis
western bumble bee
IIHYM24252 None Candidate
Endangered
G3 S1
Bombus pensylvanicus
American bumble bee
IIHYM24260 None None G3G4 S2
Brachyramphus marmoratus
marbled murrelet
ABNNN06010 Threatened Endangered G3 S2
Calyptridium parryi var. hesseae
Santa Cruz Mountains pussypaws
PDPOR09052 None None G3G4T2 S2 1B.1
Carex comosa
bristly sedge
PMCYP032Y0 None None G5 S2 2B.1
Carex saliniformis
deceiving sedge
PMCYP03BY0 None None G2 S2 1B.2
Ceanothus ferrisiae
Coyote ceanothus
PDRHA041N0 Endangered None G1 S1 1B.1
Central Dune Scrub
Central Dune Scrub
CTT21320CA None None G2 S2.2
Centromadia parryi ssp. congdonii
Congdon's tarplant
PDAST4R0P1 None None G3T2 S2 1B.1
Charadrius nivosus nivosus
western snowy plover
ABNNB03031 Threatened None G3T3 S3 SSC
Chorizanthe pungens var. hartwegiana
Ben Lomond spineflower
PDPGN040M1 Endangered None G2T1 S1 1B.1
Chorizanthe pungens var. pungens
Monterey spineflower
PDPGN040M2 Threatened None G2T2 S2 1B.2
Chorizanthe robusta var. hartwegii
Scotts Valley spineflower
PDPGN040Q1 Endangered None G2T1 S1 1B.1
Chorizanthe robusta var. robusta
robust spineflower
PDPGN040Q2 Endangered None G2T1 S1 1B.1
Cicindela hirticollis gravida
sandy beach tiger beetle
IICOL02101 None None G5T2 S2
Cicindela ohlone
Ohlone tiger beetle
IICOL026L0 Endangered None G1 S1
Clarkia concinna ssp. automixa
Santa Clara red ribbons
PDONA050A1 None None G5?T3 S3 4.3
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Species Element Code Federal Status State Status Global Rank State Rank Rare Plant
Rank/CDFW
SSC or FP
Coastal and Valley Freshwater Marsh
Coastal and Valley Freshwater Marsh
CTT52410CA None None G3 S2.1
Coelus globosus
globose dune beetle
IICOL4A010 None None G1G2 S1S2
Collinsia multicolor
San Francisco collinsia
PDSCR0H0B0 None None G2 S2 1B.2
Corynorhinus townsendii
Townsend's big-eared bat
AMACC08010 None None G4 S2 SSC
Coturnicops noveboracensis
yellow rail
ABNME01010 None None G4 S2 SSC
Cypseloides niger
black swift
ABNUA01010 None None G4 S3 SSC
Dacryophyllum falcifolium
tear drop moss
NBMUS8Z010 None None G2 S2 1B.3
Danaus plexippus plexippus pop. 1
monarch - California overwintering population
IILEPP2012 Candidate None G4T1T2Q S2
Dicamptodon ensatus
California giant salamander
AAAAH01020 None None G2G3 S2S3 SSC
Dipodomys venustus venustus
Santa Cruz kangaroo rat
AMAFD03042 None None G4T1 S1
Eastwoodiella californica
swamp harebell
PDCAM02060 None None G3 S3 1B.2
Elanus leucurus
white-tailed kite
ABNKC06010 None None G5 S3S4 FP
Emys marmorata
western pond turtle
ARAAD02030 Proposed
Threatened
None G3G4 S3 SSC
Eriogonum nudum var. decurrens
Ben Lomond buckwheat
PDPGN08492 None None G5T1 S1 1B.1
Erysimum ammophilum
sand-loving wallflower
PDBRA16010 None None G2 S2 1B.2
Erysimum teretifolium
Santa Cruz wallflower
PDBRA160N0 Endangered Endangered G1 S1 1B.1
Eucyclogobius newberryi
tidewater goby
AFCQN04010 Endangered None G3 S3 SSC
Euphilotes enoptes smithi
Smith's blue butterfly
IILEPG2026 Endangered None G5T2 S2
Fissidens pauperculus
minute pocket moss
NBMUS2W0U0 None None G3? S2 1B.2
Fissilicreagris imperialis
Empire Cave pseudoscorpion
ILARAE5010 None None G1 S1
Gilia tenuiflora ssp. arenaria
Monterey gilia
PDPLM041P2 Endangered Threatened G3G4T2 S2 1B.2
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Species Element Code Federal Status State Status Global Rank State Rank Rare Plant
Rank/CDFW
SSC or FP
Hesperocyparis abramsiana var. abramsiana
Santa Cruz cypress
PGCUP04081 Threatened Endangered G1T1 S1 1B.2
Hoita strobilina
Loma Prieta hoita
PDFAB5Z030 None None G2? S2? 1B.1
Holocarpha macradenia
Santa Cruz tarplant
PDAST4X020 Threatened Endangered G1 S1 1B.1
Horkelia cuneata var. sericea
Kellogg's horkelia
PDROS0W043 None None G4T1? S1? 1B.1
Horkelia marinensis
Point Reyes horkelia
PDROS0W0B0 None None G2 S2 1B.2
Lasiurus cinereus
hoary bat
AMACC05032 None None G3G4 S4
Lasthenia californica ssp. macrantha
perennial goldfields
PDAST5L0C5 None None G3T2 S2 1B.2
Laterallus jamaicensis coturniculus
California black rail
ABNME03041 None Threatened G3T1 S2 FP
Lavinia exilicauda harengus
Monterey hitch
AFCJB19013 None None G4T3 S3 SSC
Lessingia micradenia var. glabrata
smooth lessingia
PDAST5S062 None None G2T2 S2 1B.2
Linderiella occidentalis
California linderiella
ICBRA06010 None None G2G3 S2S3
Lytta moesta
moestan blister beetle
IICOL4C020 None None G2 S2
Malacothamnus arcuatus
arcuate bush-mallow
PDMAL0Q0E0 None None G2Q S2 1B.2
Malacothamnus hallii
Hall's bush-mallow
PDMAL0Q0F0 None None G2 S2 1B.2
Margaritifera falcata
western pearlshell
IMBIV27020 None None G5 S1S2
Maritime Coast Range Ponderosa Pine Forest
Maritime Coast Range Ponderosa Pine Forest
CTT84132CA None None G1 S1.1
Meta dolloff
Dolloff Cave spider
ILARA17010 None None G3 S3
Microseris paludosa
marsh microseris
PDAST6E0D0 None None G2 S2 1B.2
Monardella sinuata ssp. nigrescens
northern curly-leaved monardella
PDLAM18162 None None G3T2 S2 1B.2
Monolopia gracilens
woodland woollythreads
PDAST6G010 None None G3 S3 1B.2
Neochthonius imperialis
Empire Cave pseudoscorpion
ILARAD1010 None None G1 S1
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Species Element Code Federal Status State Status Global Rank State Rank Rare Plant
Rank/CDFW
SSC or FP
Neotoma fuscipes annectens
San Francisco dusky-footed woodrat
AMAFF08082 None None G5T2T3 S2S3 SSC
North Central Coast Drainage Sacramento
Sucker/Roach River
North Central Coast Drainage Sacramento
Sucker/Roach River
CARA2623CA None None GNR SNR
Northern Maritime Chaparral
Northern Maritime Chaparral
CTT37C10CA None None G1 S1.2
Oncorhynchus kisutch pop. 4
coho salmon - central California coast ESU
AFCHA02034 Endangered Endangered G5T2Q S2
Oncorhynchus mykiss irideus pop. 8
steelhead - central California coast DPS
AFCHA0209G Threatened None G5T3Q S3 SSC
Oncorhynchus mykiss irideus pop. 9
steelhead - south-central California coast DPS
AFCHA0209H Threatened None G5T2Q S2 SSC
Pandion haliaetus
osprey
ABNKC01010 None None G5 S4 WL
Pedicularis dudleyi
Dudley's lousewort
PDSCR1K180 None Rare G2 S2 1B.2
Penstemon rattanii var. kleei
Santa Cruz Mountains beardtongue
PDSCR1L5B1 None None G4T2 S2 1B.2
Pentachaeta bellidiflora
white-rayed pentachaeta
PDAST6X030 Endangered Endangered G1 S1 1B.1
Philanthus nasalis
Antioch specid wasp
IIHYM20010 None None G2 S2
Piperia candida
white-flowered rein orchid
PMORC1X050 None None G3? S3 1B.2
Plagiobothrys chorisianus var. chorisianus
Choris' popcornflower
PDBOR0V061 None None G3T1Q S1 1B.2
Plagiobothrys diffusus
San Francisco popcornflower
PDBOR0V080 None Endangered G1Q S1 1B.1
Polygonum hickmanii
Scotts Valley polygonum
PDPGN0L310 Endangered Endangered G1 S1 1B.1
Polyphylla barbata
Mount Hermon (=barbate) June beetle
IICOL68030 Endangered None G1 S2
Rana boylii pop. 4
foothill yellow-legged frog - central coast DPS
AAABH01054 Threatened Endangered G3T2 S2
Rana draytonii
California red-legged frog
AAABH01022 Threatened None G2G3 S2S3 SSC
Riparia riparia
bank swallow
ABPAU08010 None Threatened G5 S3
Scaphinotus behrensi
Behrens' snail-eating beetle
IICOL4L070 None None G2G4 S2S4
Senecio aphanactis
chaparral ragwort
PDAST8H060 None None G3 S2 2B.2
Report Printed on Friday, May 03, 2024
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California Natural Diversity Database
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Species Element Code Federal Status State Status Global Rank State Rank Rare Plant
Rank/CDFW
SSC or FP
Sidalcea malachroides
maple-leaved checkerbloom
PDMAL110E0 None None G3 S3 4.2
Stebbinsoseris decipiens
Santa Cruz microseris
PDAST6E050 None None G2 S2 1B.2
Stygobromus imperialis
Empire Cave amphipod
ICMAL05E30 None None G1 S1
Stygobromus mackenziei
Mackenzie's Cave amphipod
ICMAL05530 None None G1 S1
Taxidea taxus
American badger
AMAJF04010 None None G5 S3 SSC
Thaleichthys pacificus
eulachon
AFCHB04010 Threatened None G5 S1 SSC
Trifolium buckwestiorum
Santa Cruz clover
PDFAB402W0 None None G2 S2 1B.1
Trifolium polyodon
Pacific Grove clover
PDFAB402H0 None Rare G1 S1 1B.1
Trimerotropis infantilis
Zayante band-winged grasshopper
IIORT36030 Endangered None G1 S1
Tryonia imitator
mimic tryonia (=California brackishwater snail)
IMGASJ7040 None None G2 S2
Record Count: 113
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IPaC resource list
This report is an automatically generated list of species and other resources such as critical habitat (collectively referred to as trust resources) under the U.S. Fish and Wildlife Service's (USFWS) jurisdiction that are known or expected to be on or near the project area referenced below. The list may also include trust resources that occur outside of the project area, but that could potentially be directly or indirectly affected by activities in the project area. However, determining the likelihood and extent of effects a project may have on trust resources typically requires gathering additional site-specific (e.g., vegetation/species surveys) and project-specific (e.g., magnitude and timing of proposed activities) information.
Below is a summary of the project information you provided and contact information for the USFWS office(s) with jurisdiction in the defined project area. Please read the introduction to each section that follows (Endangered Species, Migratory Birds, USFWS Facilities, and NWI Wetlands) for additional information applicable to the trust resources addressed in that section.
Location
Santa Cruz County, California
Local office
Ventura Fish And Wildlife Office
(805) 644-1766
(805) 644-3958
[email protected]
2493 Portola Road, Suite B
Ventura, CA 93003-7726
https://www.fws.gov/Ventura
IPaC Information for Planning and Consultation U.S. Fish & Wildlife Service 408
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Endangered species
This resource list is for informational purposes only and does not constitute an analysis of project level impacts.
The primary information used to generate this list is the known or expected range of each species. Additional areas of influence (AOI) for species are also considered. An AOI includes areas outside of the species range if the species could be indirectly affected by activities in that area (e.g., placing a dam upstream of a fish population even if that fish does not occur at the dam site, may indirectly impact the species by reducing or eliminating water flow downstream). Because species can move, and site conditions can change, the species on this list are not guaranteed to be found on or near the project area. To fully determine any potential effects to species, additional site-specific and project-specific information is often required.
Section 7 of the Endangered Species Act requires Federal agencies to "request of the Secretary information whether any species which is listed or proposed to be listed may be present in the area of such proposed action" for any project that is conducted, permitted, funded, or licensed by any Federal agency. A letter from the local office and a species list which fulfills this requirement can only be obtained by requesting an official species list from either the Regulatory Review section in IPaC (see directions below) or from the local field office directly.
For project evaluations that require USFWS concurrence/review, please return to the IPaC website and request an official species list by doing the following:
1. Draw the project location and click CONTINUE.
2. Click DEFINE PROJECT.
3. Log in (if directed to do so).
4. Provide a name and description for your project.
5. Click REQUEST SPECIES LIST.
Listed species and their critical habitats are managed by the Ecological Services Program of the U.S. Fish and Wildlife Service (USFWS) and the fisheries division of the National Oceanic and Atmospheric Administration (NOAA Fisheries ).
Species and critical habitats under the sole responsibility of NOAA Fisheries are not shown on this list. Please contact NOAA Fisheries for species under their jurisdiction.
1. Species listed under the Endangered Species Act are threatened or endangered; IPaC also shows species that are candidates, or proposed, for listing. See the listing status page for more information. IPaC only shows species that are regulated by USFWS (see FAQ).
2. NOAA Fisheries, also known as the National Marine Fisheries Service (NMFS), is an office of the National Oceanic and Atmospheric Administration within the Department of Commerce.
The following species are potentially affected by activities in this location:
Birds
1 2
NAME STATUS
California Condor Gymnogyps californianus
There is final critical habitat for this species. Your location does not overlap the critical habitat.
https://ecos.fws.gov/ecp/species/8193
Endangered
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Reptiles
Amphibians
California Least Tern Sternula antillarum browni
Wherever found
No critical habitat has been designated for this species. https://ecos.fws.gov/ecp/species/8104
Endangered
Least Bell's Vireo Vireo bellii pusillus
Wherever found
There is final critical habitat for this species. Your location does not overlap the critical habitat.
https://ecos.fws.gov/ecp/species/5945
Endangered
Marbled Murrelet Brachyramphus marmoratus
There is final critical habitat for this species. Your location does not overlap the critical habitat.
https://ecos.fws.gov/ecp/species/4467
Threatened
Short-tailed Albatross Phoebastria (=Diomedea) albatrus Wherever found
No critical habitat has been designated for this species. https://ecos.fws.gov/ecp/species/433
Endangered
Western Snowy Plover Charadrius nivosus nivosus
There is final critical habitat for this species. Your location does not overlap the critical habitat.
https://ecos.fws.gov/ecp/species/8035
Threatened
Yellow-billed Cuckoo Coccyzus americanus
There is final critical habitat for this species. Your location does not overlap the critical habitat.
https://ecos.fws.gov/ecp/species/3911
Threatened
NAME STATUS
Northwestern Pond Turtle Actinemys marmorata
Wherever found
No critical habitat has been designated for this species. https://ecos.fws.gov/ecp/species/1111
Proposed Threatened
San Francisco Garter Snake Thamnophis sirtalis tetrataenia Wherever found
No critical habitat has been designated for this species. https://ecos.fws.gov/ecp/species/5956
Endangered
NAME STATUS
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Fishes
Insects
Flowering Plants
California Red-legged Frog Rana draytonii
Wherever found
There is final critical habitat for this species. Your location does not overlap the critical habitat.
https://ecos.fws.gov/ecp/species/2891
Threatened
California Tiger Salamander Ambystoma californiense
There is final critical habitat for this species. Your location does not overlap the critical habitat.
https://ecos.fws.gov/ecp/species/2076
Threatened
Foothill Yellow-legged Frog Rana boylii
No critical habitat has been designated for this species. https://ecos.fws.gov/ecp/species/5133
Threatened
NAME STATUS
Tidewater Goby Eucyclogobius newberryi
Wherever found
There is final critical habitat for this species. Your location does not overlap the critical habitat.
https://ecos.fws.gov/ecp/species/57
Endangered
NAME STATUS
Monarch Butterfly Danaus plexippus
Wherever found
No critical habitat has been designated for this species. https://ecos.fws.gov/ecp/species/9743
Candidate
NAME STATUS
Lassics Lupine Lupinus constancei
There is final critical habitat for this species. Your location does not overlap the critical habitat.
https://ecos.fws.gov/ecp/species/7976
Endangered
Marsh Sandwort Arenaria paludicola
Wherever found
No critical habitat has been designated for this species. https://ecos.fws.gov/ecp/species/2229
Endangered
Monterey Gilia Gilia tenuiflora ssp. arenaria
Wherever found
No critical habitat has been designated for this species. https://ecos.fws.gov/ecp/species/856
Endangered
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Critical habitats
Potential effects to critical habitat(s) in this location must be analyzed along with the endangered species themselves.
There are no critical habitats at this location.
You are still required to determine if your project(s) may have effects on all above listed species.
Bald & Golden Eagles
Santa Cruz Tarplant Holocarpha macradenia
Wherever found
There is final critical habitat for this species. Your location does not overlap the critical habitat.
https://ecos.fws.gov/ecp/species/6832
Threatened
Scotts Valley Polygonum Polygonum hickmanii
Wherever found
There is final critical habitat for this species. Your location does not overlap the critical habitat.
https://ecos.fws.gov/ecp/species/3222
Endangered
Scotts Valley Spineflower Chorizanthe robusta var. hartwegii Wherever found
There is final critical habitat for this species. Your location does not overlap the critical habitat.
https://ecos.fws.gov/ecp/species/7108
Endangered
Bald and golden eagles are protected under the Bald and Golden Eagle Protection Act and the Migratory Bird Treaty Act .
Any person or organization who plans or conducts activities that may result in impacts to bald or golden eagles, or their habitats , should follow appropriate regulations and consider implementing appropriate conservation measures, as described in the links below. Specifically, please review the "Supplemental Information on Migratory Birds and Eagles".
Additional information can be found using the following links:
Eagle Management https://www.fws.gov/program/eagle-management Measures for avoiding and minimizing impacts to birds https://www.fws.gov/library/collections/avoiding-andminimizing-incidental-take-migratory-birds Nationwide conservation measures for birds https://www.fws.gov/sites/default/files/documents/nationwidestandard-conservation-measures.pdf Supplemental Information for Migratory Birds and Eagles in IPaC https://www.fws.gov/media/supplementalinformation-migratory-birds-and-bald-and-golden-eagles-may-occur-project-action 1 2
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There are likely bald eagles present in your project area. For additional information on bald eagles, refer to Bald Eagle Nesting and Sensitivity to Human Activity
For guidance on when to schedule activities or implement avoidance and minimization measures to reduce impacts to migratory birds on your list, see the PROBABILITY OF PRESENCE SUMMARY below to see when these birds are most likely to be present and breeding in your project area.
BREEDING SEASON
Probability of Presence Summary
The graphs below provide our best understanding of when birds of concern are most likely to be present in your project area. This information can be used to tailor and schedule your project activities to avoid or minimize impacts to birds. Please make sure you read "Supplemental Information on Migratory Birds and Eagles", specifically the FAQ section titled "Proper Interpretation and Use of Your Migratory Bird Report" before using or attempting to interpret this report.
Probability of Presence ( )
Each green bar represents the bird's relative probability of presence in the 10km grid cell(s) your project overlaps during a particular week of the year. (A year is represented as 12 4-week months.) A taller bar indicates a higher probability of species presence. The survey effort (see below) can be used to establish a level of confidence in the presence score. One can have higher confidence in the presence score if the corresponding survey effort is also high.
How is the probability of presence score calculated? The calculation is done in three steps:
1. The probability of presence for each week is calculated as the number of survey events in the week where the species was detected divided by the total number of survey events for that week. For example, if in week 12 there were 20 survey events and the Spotted Towhee was found in 5 of them, the probability of presence of the Spotted Towhee in week 12 is 0.25.
2. To properly present the pattern of presence across the year, the relative probability of presence is calculated.
This is the probability of presence divided by the maximum probability of presence across all weeks. For example, imagine the probability of presence in week 20 for the Spotted Towhee is 0.05, and that the probability of presence at week 12 (0.25) is the maximum of any week of the year. The relative probability of presence on week 12 is 0.25/0.25 = 1; at week 20 it is 0.05/0.25 = 0.2.
3. The relative probability of presence calculated in the previous step undergoes a statistical conversion so that all possible values fall between 0 and 10, inclusive. This is the probability of presence score.
To see a bar's probability of presence score, simply hover your mouse cursor over the bar.
Breeding Season ( )
Yellow bars denote a very liberal estimate of the time-frame inside which the bird breeds across its entire range. If there are no yellow bars shown for a bird, it does not breed in your project area.
Survey Effort ( )
NAME
Bald Eagle Haliaeetus leucocephalus
This is not a Bird of Conservation Concern (BCC) in this area, but warrants attention because of the Eagle Act or for potential susceptibilities in offshore areas from certain types of development or activities.
Breeds Jan 1 to Aug 31
Golden Eagle Aquila chrysaetos
This is not a Bird of Conservation Concern (BCC) in this area, but warrants attention because of the Eagle Act or for potential susceptibilities in offshore areas from certain types of development or activities.
https://ecos.fws.gov/ecp/species/1680
Breeds Jan 1 to Aug 31
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probability of presence breeding season survey effort no data Vertical black lines superimposed on probability of presence bars indicate the number of surveys performed for that species in the 10km grid cell(s) your project area overlaps. The number of surveys is expressed as a range, for example, 33 to 64 surveys.
To see a bar's survey effort range, simply hover your mouse cursor over the bar.
No Data ( )
A week is marked as having no data if there were no survey events for that week.
Survey Timeframe
Surveys from only the last 10 years are used in order to ensure delivery of currently relevant information. The exception to this is areas off the Atlantic coast, where bird returns are based on all years of available data, since data in these areas is currently much more sparse.
SPECIES JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Bald Eagle
Non-BCC Vulnerable
Golden Eagle
Non-BCC Vulnerable
What does IPaC use to generate the potential presence of bald and golden eagles in my specified location? The potential for eagle presence is derived from data provided by the Avian Knowledge Network (AKN). The AKN data is based on a growing collection of survey, banding, and citizen science datasets and is queried and filtered to return a list of those birds reported as occurring in the 10km grid cell(s) which your project intersects, and that have been identified as warranting special attention because they are a BCC species in that area, an eagle (Eagle Act requirements may apply). To see a list of all birds potentially present in your project area, please visit the Rapid Avian Information Locator (RAIL) Tool.
What does IPaC use to generate the probability of presence graphs of bald and golden eagles in my specified location? The Migratory Bird Resource List is comprised of USFWS Birds of Conservation Concern (BCC) and other species that may warrant special attention in your project location.
The migratory bird list generated for your project is derived from data provided by the Avian Knowledge Network (AKN). The AKN data is based on a growing collection of survey, banding, and citizen science datasets and is queried and filtered to return a list of those birds reported as occurring in the 10km grid cell(s) which your project intersects, and that have been identified as warranting special attention because they are a BCC species in that area, an eagle (Eagle Act requirements may apply), or a species that has a particular vulnerability to offshore activities or development.
Again, the Migratory Bird Resource list includes only a subset of birds that may occur in your project area. It is not representative of all birds that may occur in your project area. To get a list of all birds potentially present in your project area, please visit the Rapid Avian Information Locator (RAIL) Tool.
What if I have eagles on my list?
If your project has the potential to disturb or kill eagles, you may need to obtain a permit to avoid violating the Eagle Act should such impacts occur. Please contact your local Fish and Wildlife Service Field Office if you have questions.
Migratory birds
Certain birds are protected under the Migratory Bird Treaty Act and the Bald and Golden Eagle Protection Act .
Any person or organization who plans or conducts activities that may result in impacts to migratory birds, eagles, and their habitats should follow appropriate regulations and consider implementing appropriate conservation measures, as described in the links below. Specifically, please review the "Supplemental Information on Migratory 1 2
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The birds listed below are birds of particular concern either because they occur on the USFWS Birds of Conservation Concern (BCC) list or warrant special attention in your project location. To learn more about the levels of concern for birds on your list and how this list is generated, see the FAQ below. This is not a list of every bird you may find in this location, nor a guarantee that every bird on this list will be found in your project area. To see exact locations of where birders and the general public have sighted birds in and around your project area, visit the E-bird data mapping tool (Tip: enter your location, desired date range and a species on your list). For projects that occur off the Atlantic Coast, additional maps and models detailing the relative occurrence and abundance of bird species on your list are available. Links to additional information about Atlantic Coast birds, and other important information about your migratory bird list, including how to properly interpret and use your migratory bird report, can be found below.
For guidance on when to schedule activities or implement avoidance and minimization measures to reduce impacts to migratory birds on your list, see the PROBABILITY OF PRESENCE SUMMARY below to see when these birds are most likely to be present and breeding in your project area.
BREEDING SEASON
Birds and Eagles".
1. The Migratory Birds Treaty Act of 1918.
2. The Bald and Golden Eagle Protection Act of 1940.
Additional information can be found using the following links:
Eagle Management https://www.fws.gov/program/eagle-management Measures for avoiding and minimizing impacts to birds https://www.fws.gov/library/collections/avoiding-andminimizing-incidental-take-migratory-birds Nationwide conservation measures for birds https://www.fws.gov/sites/default/files/ documents/nationwidestandard-conservation-measures.pdf Supplemental Information for Migratory Birds and Eagles in IPaC https://www.fws.gov/media/supplementalinformation-migratory-birds-and-bald-and-golden-eagles-may-occur-project-action NAME
Allen's Hummingbird Selasphorus sasin
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
https://ecos.fws.gov/ecp/species/9637
Breeds Feb 1 to Jul 15
Bald Eagle Haliaeetus leucocephalus
This is not a Bird of Conservation Concern (BCC) in this area, but warrants attention because of the Eagle Act or for potential susceptibilities in offshore areas from certain types of development or activities.
Breeds Jan 1 to Aug 31
Belding's Savannah Sparrow Passerculus sandwichensis beldingi This is a Bird of Conservation Concern (BCC) only in particular Bird Conservation Regions (BCRs) in the continental USA
https://ecos.fws.gov/ecp/species/8
Breeds Apr 1 to Aug 15
Black Oystercatcher Haematopus bachmani
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
https://ecos.fws.gov/ecp/species/9591
Breeds Apr 15 to Oct 31
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Black Skimmer Rynchops niger
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
https://ecos.fws.gov/ecp/species/5234
Breeds May 20 to Sep 15
Black Swift Cypseloides niger
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
https://ecos.fws.gov/ecp/species/8878
Breeds Jun 15 to Sep 10
Black Tern Chlidonias niger surinamenisis
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
https://ecos.fws.gov/ecp/species/3093
Breeds May 15 to Aug 20
Black Turnstone Arenaria melanocephala
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
Breeds elsewhere
Bullock's Oriole Icterus bullockii
This is a Bird of Conservation Concern (BCC) only in particular Bird Conservation Regions (BCRs) in the continental USA
Breeds Mar 21 to Jul 25
California Gull Larus californicus
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
Breeds Mar 1 to Jul 31
California Thrasher Toxostoma redivivum
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
Breeds Jan 1 to Jul 31
Clark's Grebe Aechmophorus clarkii
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
Breeds Jun 1 to Aug 31
Common Yellowthroat Geothlypis trichas sinuosa
This is a Bird of Conservation Concern (BCC) only in particular Bird Conservation Regions (BCRs) in the continental USA
https://ecos.fws.gov/ecp/species/2084
Breeds May 20 to Jul 31
Elegant Tern Thalasseus elegans
This is a Bird of Conservation Concern (BCC) only in particular Bird Conservation Regions (BCRs) in the continental USA
https://ecos.fws.gov/ecp/species/8561
Breeds Apr 5 to Aug 5
Golden Eagle Aquila chrysaetos
This is not a Bird of Conservation Concern (BCC) in this area, but warrants attention because of the Eagle Act or for potential susceptibilities in offshore areas from certain types of development or activities.
https://ecos.fws.gov/ecp/species/1680
Breeds Jan 1 to Aug 31
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Heermann's Gull Larus heermanni
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
Breeds Mar 15 to Aug 31
Lawrence's Goldfinch Spinus lawrencei
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
https://ecos.fws.gov/ecp/species/9464
Breeds Mar 20 to Sep 20
Marbled Godwit Limosa fedoa
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
https://ecos.fws.gov/ecp/species/9481
Breeds elsewhere
Northern Harrier Circus hudsonius
This is a Bird of Conservation Concern (BCC) only in particular Bird Conservation Regions (BCRs) in the continental USA
https://ecos.fws.gov/ecp/species/8350
Breeds Apr 1 to Sep 15
Nuttall's Woodpecker Dryobates nuttallii
This is a Bird of Conservation Concern (BCC) only in particular Bird Conservation Regions (BCRs) in the continental USA
https://ecos.fws.gov/ecp/species/9410
Breeds Apr 1 to Jul 20
Oak Titmouse Baeolophus inornatus
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
https://ecos.fws.gov/ecp/species/9656
Breeds Mar 15 to Jul 15
Olive-sided Flycatcher Contopus cooperi
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
https://ecos.fws.gov/ecp/species/3914
Breeds May 20 to Aug 31
Red Knot Calidris canutus roselaari
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
https://ecos.fws.gov/ecp/species/8880
Breeds elsewhere
Santa Barbara Song Sparrow Melospiza melodia graminea
This is a Bird of Conservation Concern (BCC) only in particular Bird Conservation Regions (BCRs) in the continental USA
https://ecos.fws.gov/ecp/species/5513
Breeds Mar 1 to Sep 5
Short-billed Dowitcher Limnodromus griseus
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
https://ecos.fws.gov/ecp/species/9480
Breeds elsewhere
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Probability of Presence Summary
The graphs below provide our best understanding of when birds of concern are most likely to be present in your project area. This information can be used to tailor and schedule your project activities to avoid or minimize impacts to birds. Please make sure you read "Supplemental Information on Migratory Birds and Eagles", specifically the FAQ section titled "Proper Interpretation and Use of Your Migratory Bird Report" before using or attempting to interpret this report.
Probability of Presence ( )
Each green bar represents the bird's relative probability of presence in the 10km grid cell(s) your project overlaps during a particular week of the year. (A year is represented as 12 4-week months.) A taller bar indicates a higher probability of species presence. The survey effort (see below) can be used to establish a level of confidence in the presence score. One can have higher confidence in the presence score if the corresponding survey effort is also high.
How is the probability of presence score calculated? The calculation is done in three steps:
1. The probability of presence for each week is calculated as the number of survey events in the week where the species was detected divided by the total number of survey events for that week. For example, if in week 12 there were 20 survey events and the Spotted Towhee was found in 5 of them, the probability of presence of the Spotted Towhee in week 12 is 0.25.
2. To properly present the pattern of presence across the year, the relative probability of presence is calculated.
This is the probability of presence divided by the maximum probability of presence across all weeks. For example, imagine the probability of presence in week 20 for the Spotted Towhee is 0.05, and that the probability of presence at week 12 (0.25) is the maximum of any week of the year. The relative probability of presence on week 12 is 0.25/0.25 = 1; at week 20 it is 0.05/0.25 = 0.2.
Tricolored Blackbird Agelaius tricolor
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
https://ecos.fws.gov/ecp/species/3910
Breeds Mar 15 to Aug 10
Western Grebe aechmophorus occidentalis
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
https://ecos.fws.gov/ecp/species/6743
Breeds Jun 1 to Aug 31
Western Gull Larus occidentalis
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
Breeds Apr 21 to Aug 25
Western Screech-owl Megascops kennicottii cardonensis
This is a Bird of Conservation Concern (BCC) only in particular Bird Conservation Regions (BCRs) in the continental USA
Breeds Mar 1 to Jun 30
Willet Tringa semipalmata
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
Breeds elsewhere
Wrentit Chamaea fasciata
This is a Bird of Conservation Concern (BCC) throughout its range in the continental USA and Alaska.
Breeds Mar 15 to Aug 10
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probability of presence breeding season survey effort no data
3. The relative probability of presence calculated in the previous step undergoes a statistical conversion so that all possible values fall between 0 and 10, inclusive. This is the probability of presence score.
To see a bar's probability of presence score, simply hover your mouse cursor over the bar.
Breeding Season ( )
Yellow bars denote a very liberal estimate of the time-frame inside which the bird breeds across its entire range. If there are no yellow bars shown for a bird, it does not breed in your project area.
Survey Effort ( )
Vertical black lines superimposed on probability of presence bars indicate the number of surveys performed for that species in the 10km grid cell(s) your project area overlaps. The number of surveys is expressed as a range, for example, 33 to 64 surveys.
To see a bar's survey effort range, simply hover your mouse cursor over the bar.
No Data ( )
A week is marked as having no data if there were no survey events for that week.
Survey Timeframe
Surveys from only the last 10 years are used in order to ensure delivery of currently relevant information. The exception to this is areas off the Atlantic coast, where bird returns are based on all years of available data, since data in these areas is currently much more sparse.
SPECIES JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Allen's Hummingbird
BCC Rangewide (CON)
Bald Eagle
Non-BCC Vulnerable
Belding's Savannah
Sparrow
BCC - BCR
Black Oystercatcher
BCC Rangewide (CON)
Black Skimmer
BCC Rangewide (CON)
Black Swift
BCC Rangewide (CON)
Black Tern
BCC Rangewide (CON)
Black Turnstone
BCC Rangewide (CON)
Bullock's Oriole
BCC - BCR
California Gull
BCC Rangewide (CON)
California Thrasher
BCC Rangewide (CON)
Clark's Grebe
BCC Rangewide (CON)
SPECIES JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC419 Item 9 A.
Common
Yellowthroat
BCC - BCR
Elegant Tern
BCC - BCR
Golden Eagle
Non-BCC Vulnerable
Heermann's Gull
BCC Rangewide (CON)
Lawrence's Goldfinch
BCC Rangewide (CON)
Marbled Godwit
BCC Rangewide (CON)
Northern Harrier
BCC - BCR
Nuttall's Woodpecker
BCC - BCR
Oak Titmouse
BCC Rangewide (CON)
Olive-sided Flycatcher
BCC Rangewide (CON)
Red Knot
BCC Rangewide (CON)
Santa Barbara Song
Sparrow
BCC - BCR
SPECIES JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Short-billed
Dowitcher
BCC Rangewide (CON)
Tricolored Blackbird
BCC Rangewide (CON)
Western Grebe
BCC Rangewide (CON)
Western Gull
BCC Rangewide (CON)
Western Screech-owl
BCC - BCR
Willet
BCC Rangewide (CON)
Wrentit
BCC Rangewide (CON)
Tell me more about conservation measures I can implement to avoid or minimize impacts to migratory birds.
Nationwide Conservation Measures describes measures that can help avoid and minimize impacts to all birds at any location year round. Implementation of these measures is particularly important when birds are most likely to occur in the project area. When birds may be breeding in the area, identifying the locations of any active nests and avoiding their destruction is a very helpful impact minimization measure. To see when birds are most likely to occur and be breeding in your project area, view the Probability of Presence Summary. Additional measures or permits may be advisable depending on the type of activity you are conducting and the type of infrastructure or bird species present on your project site. 420 Item 9 A.
What does IPaC use to generate the list of migratory birds that potentially occur in my specified location? The Migratory Bird Resource List is comprised of USFWS Birds of Conservation Concern (BCC) and other species that may warrant special attention in your project location.
The migratory bird list generated for your project is derived from data provided by the Avian Knowledge Network (AKN). The AKN data is based on a growing collection of survey, banding, and citizen science datasets and is queried and filtered to return a list of those birds reported as occurring in the 10km grid cell(s) which your project intersects, and that have been identified as warranting special attention because they are a BCC species in that area, an eagle (Eagle Act requirements may apply), or a species that has a particular vulnerability to offshore activities or development.
Again, the Migratory Bird Resource list includes only a subset of birds that may occur in your project area. It is not representative of all birds that may occur in your project area. To get a list of all birds potentially present in your project area, please visit the Rapid Avian Information Locator (RAIL) Tool.
What does IPaC use to generate the probability of presence graphs for the migratory birds potentially occurring in my specified location?
The probability of presence graphs associated with your migratory bird list are based on data provided by the Avian Knowledge Network (AKN). This data is derived from a growing collection of survey, banding, and citizen science datasets.
Probability of presence data is continuously being updated as new and better information becomes available. To learn more about how the probability of presence graphs are produced and how to interpret them, go the Probability of Presence Summary and then click on the "Tell me about these graphs" link.
How do I know if a bird is breeding, wintering or migrating in my area? To see what part of a particular bird's range your project area falls within (i.e. breeding, wintering, migrating or year-round), you may query your location using the RAIL Tool and look at the range maps provided for birds in your area at the bottom of the profiles provided for each bird in your results. If a bird on your migratory bird species list has a breeding season associated with it, if that bird does occur in your project area, there may be nests present at some point within the timeframe specified. If "Breeds elsewhere" is indicated, then the bird likely does not breed in your project area.
What are the levels of concern for migratory birds?
Migratory birds delivered through IPaC fall into the following distinct categories of concern:
1. "BCC Rangewide" birds are Birds of Conservation Concern (BCC) that are of concern throughout their range anywhere within the USA (including Hawaii, the Pacific Islands, Puerto Rico, and the Virgin Islands);
2. "BCC - BCR" birds are BCCs that are of concern only in particular Bird Conservation Regions (BCRs) in the continental USA; and
3. "Non-BCC - Vulnerable" birds are not BCC species in your project area, but appear on your list either because of the Eagle Act requirements (for eagles) or (for non-eagles) potential susceptibilities in offshore areas from certain types of development or activities (e.g. offshore energy development or longline fishing).
Although it is important to try to avoid and minimize impacts to all birds, efforts should be made, in particular, to avoid and minimize impacts to the birds on this list, especially eagles and BCC species of rangewide concern. For more information on conservation measures you can implement to help avoid and minimize migratory bird impacts and requirements for eagles, please see the FAQs for these topics.
Details about birds that are potentially affected by offshore projects For additional details about the relative occurrence and abundance of both individual bird species and groups of bird species within your project area off the Atlantic Coast, please visit the Northeast Ocean Data Portal. The Portal also offers data and information about other taxa besides birds that may be helpful to you in your project review. Alternately, you may download the bird model results files underlying the portal maps through the NOAA NCCOS Integrative Statistical Modeling and Predictive Mapping of Marine Bird Distributions and Abundance on the Atlantic Outer Continental Shelf project webpage.
Bird tracking data can also provide additional details about occurrence and habitat use throughout the year, including migration.
Models relying on survey data may not include this information. For additional information on marine bird tracking data, see the Diving Bird Study and the nanotag studies or contact Caleb Spiegel or Pam Loring. 421 Item 9 A.
What if I have eagles on my list?
If your project has the potential to disturb or kill eagles, you may need to obtain a permit to avoid violating the Eagle Act should such impacts occur.
Proper Interpretation and Use of Your Migratory Bird Report The migratory bird list generated is not a list of all birds in your project area, only a subset of birds of priority concern. To learn more about how your list is generated, and see options for identifying what other birds may be in your project area, please see the FAQ "What does IPaC use to generate the migratory birds potentially occurring in my specified location". Please be aware this report provides the "probability of presence" of birds within the 10 km grid cell(s) that overlap your project; not your exact project footprint.
On the graphs provided, please also look carefully at the survey effort (indicated by the black vertical bar) and for the existence of the "no data" indicator (a red horizontal bar). A high survey effort is the key component. If the survey effort is high, then the probability of presence score can be viewed as more dependable. In contrast, a low survey effort bar or no data bar means a lack of data and, therefore, a lack of certainty about presence of the species. This list is not perfect; it is simply a starting point for identifying what birds of concern have the potential to be in your project area, when they might be there, and if they might be breeding (which means nests might be present). The list helps you know what to look for to confirm presence, and helps guide you in knowing when to implement conservation measures to avoid or minimize potential impacts from your project activities, should presence be confirmed. To learn more about conservation measures, visit the FAQ "Tell me about conservation measures I can implement to avoid or minimize impacts to migratory birds" at the bottom of your migratory bird trust resources page.
Facilities
National Wildlife Refuge lands
Any activity proposed on lands managed by the National Wildlife Refuge system must undergo a 'Compatibility Determination' conducted by the Refuge. Please contact the individual Refuges to discuss any questions or concerns.
There are no refuge lands at this location.
Fish hatcheries
There are no fish hatcheries at this location.
Wetlands in the National Wetlands Inventory (NWI)
Impacts to NWI wetlands and other aquatic habitats may be subject to regulation under Section 404 of the Clean Water Act, or other State/Federal statutes.
For more information please contact the Regulatory Program of the local U.S. Army Corps of Engineers District.
Please note that the NWI data being shown may be out of date. We are currently working to update our NWI data set. We recommend you verify these results with a site visit to determine the actual extent of wetlands on site.
This location overlaps the following wetlands:
RIVERINE
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NOTE: This initial screening does not replace an on-site delineation to determine whether wetlands occur.
Additional information on the NWI data is provided below.
Data limitations
The Service's objective of mapping wetlands and deepwater habitats is to produce reconnaissance level information on the location, type and size of these resources. The maps are prepared from the analysis of high altitude imagery. Wetlands are identified based on vegetation, visible hydrology and geography. A margin of error is inherent in the use of imagery; thus, detailed on-the-ground inspection of any particular site may result in revision of the wetland boundaries or classification established through image analysis.
The accuracy of image interpretation depends on the quality of the imagery, the experience of the image analysts, the amount and quality of the collateral data and the amount of ground truth verification work conducted. Metadata should be consulted to determine the date of the source imagery used and any mapping problems.
Wetlands or other mapped features may have changed since the date of the imagery or field work. There may be occasional differences in polygon boundaries or classifications between the information depicted on the map and the actual conditions on site.
Data exclusions
Certain wetland habitats are excluded from the National mapping program because of the limitations of aerial imagery as the primary data source used to detect wetlands. These habitats include seagrasses or submerged aquatic vegetation that are found in the intertidal and subtidal zones of estuaries and nearshore coastal waters. Some deepwater reef communities (coral or tuberficid worm reefs) have also been excluded from the inventory. These habitats, because of their depth, go undetected by aerial imagery.
Data precautions
Federal, state, and local regulatory agencies with jurisdiction over wetlands may define and describe wetlands in a different manner than that used in this inventory. There is no attempt, in either the design or products of this inventory, to define the limits of proprietary jurisdiction of any Federal, state, or local government or to establish the geographical scope of the regulatory programs of government agencies. Persons intending to engage in activities involving modifications within or adjacent to wetland areas should seek the advice of appropriate Federal, state, or local agencies concerning specified agency regulatory programs and proprietary jurisdictions that may affect such activities.
R1UBV
A full description for each wetland code can be found at the National Wetlands Inventory website 423
Item 9 A.
Attachment C: Special-Status Species Table
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Stockton Bridge Debris Project Special-Status Species Table Special-Status Species Table
Soquel, Felton, Laurel, Loma Prieta, Santa Cruz, and Watsonville West Quadrangles Species Status
(Service/CDFW/CNPS) General Habitat Potential Occurrence within Survey Area
MAMMALS
Antrozous pallidus
Pallid bat
-- / CSC / -- Occurs in a wide variety of habitats including grasslands, shrublands, arid desert areas, oak
savanna, coastal forested areas, and coniferous
forests of the mountain regions of California. Most
common in open, dry habitats with rocky areas for
roosting. Day roosts include caves, crevices, mines,
and occasionally hollow trees and buildings. Seems
to prefer rocky outcrops, cliffs, and crevices with
access to open habitats for foraging. Similar
structures are used for night roosting and will also
use more open sites such as eaves, awnings, and
open areas under bridges for feeding roosts.
Low
Suitable roosting habitat may be present under the
bridge; however, limited foraging habitat is present
surrounding the survey area.
Corynorhinus townsendii
Townsend’s big-eared bat
-- / CSC / -- Found primarily in rural settings from inland deserts to coastal redwoods, oak woodland of the inner
Coast Ranges and Sierra foothills, and low to midelevation mixed coniferous-deciduous forests.
Typically roost during the day in limestone caves,
lava tubes, and mines, but can roost in buildings
that offer suitable conditions. Night roosts are in
more open settings and include bridges, rock
crevices, and trees.
Low
Suitable roosting habitat may be present under the
bridge; however, limited foraging habitat is present
surrounding the survey area.
Neotoma fuscipes annectens
San Francisco dusky-footed
woodrat
-- / CSC / -- Forest habitats of moderate canopy with moderate to dense understory. Also occurs in chaparral
habitats.
Unlikely
No suitable habitat is present within the survey area.
Taxidea taxus
American badger
-- / CSC / -- Dry, open grasslands, fields, pastures savannas, and mountain meadows near timberline are preferred.
The principal requirements seem to be sufficient
food, friable soils, and relatively open, uncultivated
grounds.
Unlikely
No suitable habitat is present within the survey area.
BIRDS
Agelaius tricolor
Tricolored blackbird
(nesting colony)
-- / SC&CSC / -- Nest in colonies in dense riparian vegetation, along rivers, lagoons, lakes, and ponds. Forages over
grassland or aquatic habitats.
Unlikely
Suitable habitat is not present in riparian habitat
adjacent to the survey area.
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Stockton Bridge Debris Project Special-Status Species Table Species Status
(Service/CDFW/CNPS) General Habitat Potential Occurrence within Survey Area Athene cunicularia
Burrowing owl (burrow sites &
some wintering sites)
-- / CSC / -- Year-round resident of open, dry grassland and desert habitats, and in grass, forb and open shrub
stages of pinyon-juniper and ponderosa pine
habitats. Frequents open grasslands and shrublands
with perches and burrows. Use rodent burrows
(often California ground squirrel) for roosting and
nesting cover. Pipes, culverts, and nest boxes may
be substituted for burrows in areas where burrows
are not available.
Unlikely
No suitable habitat is present within the survey area.
Aquila chrysaetos
Golden eagle (nesting & wintering)
--/ CFP / -- Use rolling foot-hills, mountain terrain, wide arid plateaus deeply cut by streams and canyons, open
mountain slopes, cliffs, and rocky outcrops. Nest in
secluded cliffs with overhanging ledges as well as
large trees.
Unlikely
No suitable nesting or wintering habitat is present
within the survey area.
Brachyramphus marmoratus
Marbled Murrelet
FT / SE / -- Occur year-round in marine subtidal and pelagic habitats from the Oregon border to Point Sal. Partial
to coastlines with stands of mature redwood and
Douglas-fir. Requires dense mature forests of
redwood and/or Douglas-fir for breeding and
nesting.
Unlikely
No suitable habitat within the survey area.
Coccyzus americanus occidentalis
Western yellow-billed cuckoo
FT / SE / -- Inhabits extensive deciduous riparian thickets or forests with dense, low-level or understory foliage,
slow-moving watercourses, backwaters, or seeps.
Willow almost always a dominant component of the
vegetation.
Unlikely
Marginal habitat is present in the riparian habitat
adjacent to the survey area; however, the riparian
area does not provide the dense canopy this species
requires. There are no CNDDB occurrences of this
species within the quadrangles reviewed.
Coturnicops noveboracensis
Yellow rail
-- / CSC / -- Wet meadows and coastal tidal marshes. Occurs year round in California, but in two primary
seasonal roles: as a very local breeder in the
northeastern interior and as a winter visitor (early
Oct to mid-Apr) on the coast and in the Suisun
Marsh region.
Unlikely
No suitable habitat is present within the survey area.
Charadrius alexandrinus nivosus
Western snowy plover (nesting)
FT / CSC / -- Sandy beaches on marine and estuarine shores, also salt pond levees and the shores of large alkali lakes.
Requires sandy, gravelly or friable soil substrate for
nesting.
Unlikely
No suitable habitat is present within the survey area.
Cypseloides niger
Black swift
(nesting)
-- / CSC / -- Regularly nests in moist crevice or cave on sea cliffs above the surf, or on cliffs behind, or adjacent to, waterfalls in deep canyons. Forages widely over
many habitats.
Unlikely
No suitable habitat is present within the survey area.
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Stockton Bridge Debris Project Special-Status Species Table Species Status
(Service/CDFW/CNPS) General Habitat Potential Occurrence within Survey Area Elanus leucurus
White-tailed kite (nesting)
-- / CFP / -- Open groves, river valleys, marshes, and grasslands.
Prefer such areas with low roosts (fences etc.). Nest
in shrubs and trees adjacent to grasslands.
Low
Trees within the survey area may provide suitable
nesting habitat; however, limited foraging habitat is
available surrounding the survey area.
Gymnogyps californianus
California condor
FE / SE / -- Roosting sites in isolated rocky cliffs, rugged chaparral, and pine covered mountains 2000-6000
feet above sea level. Foraging area removed from
nesting/roosting site (includes rangeland and coastal
area - up to 19-mile commute one way). Nest sites
in cliffs, crevices, potholes.
Unlikely
No suitable nesting habitat is present within the
survey area. There are no CNDDB occurrences of
this species within the quadrangles reviewed.
Laterallus jamaicensis coturniculus
California black rail
-- / ST&CFP / -- Inhabits freshwater marshes, wet meadows & shallow margins of saltwater marshes bordering
larger bays. Needs water depths of about 1 inch that
does not fluctuate during the year & dense
vegetation for nesting habitat.
Unlikely
No suitable habitat is present within the survey area.
Phoebastria albatrus
Short-tailed albatross
FE / -- / -- During the non-breeding season, short-tailed albatross range along the Pacific Rim, from
southern Japan to the west coast of Canada and the
United States, primarily along continental shelf
margin. The species breeds primarily on remote
islands in the western Pacific.
Unlikely
No suitable habitat is present within the survey area.
Riparia riparia
Bank swallow (nesting)
-- / ST / -- Nest colonially in sand banks. Found near water; fields, marshes, streams, and lakes.
Unlikely
No suitable habitat is present within the survey area
as the banks of Soquel Creek are channelized.
Sternula antillarum browni
California least tern
FE / SE / -- Prefers undisturbed nest sites on open,
sandy/gravelly shores near shallow-water feeding
areas in estuaries. Sea beaches, bays, large rivers,
bars.
Unlikely
No suitable habitat is present within the survey area.
No CNDDB occurrences are reported within the
quadrangles evaluated.
Vireo bellii pusillus
Least Bell’s vireo
FE / SE / -- Riparian areas and drainages. Breed in willow riparian forest supporting a dense, shrubby
understory. Oak woodland with a willow riparian
understory is also used in some areas, and
individuals sometimes enter adjacent chaparral,
coastal sage scrub, or desert scrub habitats to
forage.
Unlikely
Marginal habitat is present in the riparian habitat
adjacent to the survey area; however, the riparian
area does not provide the dense canopy this species
requires.
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Stockton Bridge Debris Project Special-Status Species Table Species Status
(Service/CDFW/CNPS) General Habitat Potential Occurrence within Survey Area
REPTILES AND AMPHIBIANS
Ambystoma californiense
California tiger salamander
FT / ST / -- Annual grassland and grassy understory of valleyfoothill hardwood habitats in central and northern California. Need underground refuges and vernal
pools or other seasonal water sources.
Unlikely
No suitable breeding or upland habitat is present
within the survey area. There are no CNDDB
occurrences within the dispersal range (1.3 miles, 2.2
km) of this species. The nearest CNDDB occurrence
is located approximately seven miles from the survey
area in Ellicott Pond, a known CTS breeding
resource.
Ambystoma macrodactylum
croceum
Santa Cruz long-toed salamander
FE / SE&CFP / -- Preferred habitats include ponderosa pine, montane hardwood-conifer, mixed conifer, montane riparian,
red fir and wet meadows. Occurs in a small number
of localities in Santa Cruz and Monterey Counties.
Adults spend the majority of the time in
underground burrows and beneath objects. Larvae
prefer shallow water with clumps of vegetation.
Unlikely
No suitable breeding or upland habitat is present
within the survey area. There are no CNDDB
occurrences or potential breeding resources within
the dispersal range (1.0-mile, 1.6 km) of this species.
The nearest CNDDB occurrence is located
approximately 4.0 miles from the survey area in
Valencia Lagoon, a known SCLTS breeding
resource.
Aneides niger
Santa Cruz black salamander
-- / CSC / -- Occurs in the fog belt of the outer Coastal Range in mesic forests. This species occurs in moist
streamside microhabitats. This species is often
found in shallow standing water or seeps. Small
geographical range consisting of woodland habitat
within the Santa Cruz Mountains in western Santa
Clara, northern Santa Cruz, and southernmost San
Mateo Counties.
Unlikely
No suitable habitat is present within the survey area.
Anniella pulchra
Northern California legless lizard
-- / CSC / -- Requires moist, warm habitats with loose soil for burrowing and prostrate plant cover, often forages
in leaf litter at plant bases; may be found on
beaches, sandy washes, and in woodland, chaparral,
and riparian areas.
Unlikely
No suitable habitat is present within the survey area.
Dicamptodon ensatus
California giant salamander
-- / CSC / -- Occurs within the Coast Range from just north of the southern border of Mendocino County to
southern Santa Cruz County. Found in wet coastal
forests in or around clear, cold permanent and semipermanent streams and seepages. Typically, within elevations ranging from sea level to approximately
3000 feet.
Unlikely
No suitable habitat is present within the survey area.
Emys marmorata
Western pond turtle
FC / CSC / -- Associated with permanent or nearly permanent water in a wide variety of habitats including
streams, lakes, ponds, irrigation ditches, etc.
Require basking sites such as partially submerged
logs, rocks, mats of vegetation, or open banks.
Moderate
Suitable habitat is present within the survey area in
Soquel Creek. The nearest CNDDB occurrence is
located approximately one mile upstream from the
survey area in Soquel Creek.
428
Item 9 A.
Stockton Bridge Debris Project Special-Status Species Table Species Status
(Service/CDFW/CNPS) General Habitat Potential Occurrence within Survey Area Rana boylii
Foothill yellow-legged frog
-- / SC&CSC / -- Partly shaded, shallow streams and riffles with a rocky substrate in a variety of habitats, including
hardwood, pine, and riparian forests, scrub,
chaparral, and wet meadows. Rarely encountered
far from permanent water.
Low
This species is known to occur in upstream areas of
Soquel Creek, however suitable habitat is not present
within the survey area within Soquel Creek. The
creek within the survey area is confined to the
engineered channel that does not provide the
constituent elements necessary for this species to
breed or forage. The nearest CNDDB occurrence
(#102) is located approximately one mile upstream in
Soquel Creek where all life stages of the species have
been found as recently as 2021.
Rana draytonii
California red-legged frog
FT / CSC / -- Lowlands and foothills in or near permanent or lateseason sources of deep water with dense, shrubby, or emergent riparian vegetation. During late
summer or fall adults are known to utilize a variety
of upland habitats with leaf litter or mammal
burrows.
Unlikely
No suitable breeding habitat is present within the
survey area. The creek within the survey area is
confined to the engineered channel that does not
provide the constituent elements necessary for this
species to breed or forage. There are no CNDDB
occurrences located within the known dispersal
distance of this species (1.0-mile, 1.6 km). The
nearest CNDDB occurrence is located approximately
4.0 miles from the survey area in Valencia Lagoon.
Thamnophis sirtalis tetrataenia
San Francisco garter snake
FE / SE&CFP / -- An extremely scarce subspecies which only occurs in the vicinity of ponds and reservoirs in San Mateo
County. Observed most often in the vicinity of
standing water (mainly ponds, lakes, marshes, and
sloughs); however, temporary ponds and other
seasonal water bodies are also used. Emergent and
bankside vegetation (such as cattails, bulrush, and
spike rushes) are preferred for cover. Use open
spaces between stream/pond habitats and grasslands
for basking.
Unlikely
Marginal habitat is present within the survey area;
however, there are no CNDDB occurrences of this
species within the quadrangles reviewed.
FISH
Eucyclogobius newberryi
Tidewater goby
FE / CSC / -- Brackish water habitats, found in shallow lagoons and lower stream reaches. Tidewater gobies appear
to be naturally absent (now and historically) from
three large stretches of coastline where lagoons or
estuaries are absent and steep topography or swift
currents may prevent tidewater gobies from
dispersing between adjacent localities. The
southernmost large, natural gap occurs between the
Salinas River in Monterey County and Arroyo del
Oso in San Luis Obispo County.
High
This species is known to occur within Soquel Creek.
429
Item 9 A.
Stockton Bridge Debris Project Special-Status Species Table Species Status
(Service/CDFW/CNPS) General Habitat Potential Occurrence within Survey Area Lavinia exilicauda harengus
Monterey hitch
(Pajaro/Salinas hitch)
-- / CSC / -- Found only within the Pajaro and Salinas River systems. Can occupy a wide variety of habitats,
however, they are most abundant in lowland areas
with large pools or small reservoirs that mimic such
conditions. May be found in brackish water
conditions within the Salinas River lagoon during
the early summer months when the sandbar forms at
the mouth of the river.
Not Present
This species is only known to occur within the Pajaro
and Salinas Rivers.
Oncorhynchus kisutch
Coho salmon
(central California coast ESU)
FE / SE / -- All naturally spawned populations from Punta Gorda south to and including the San Lorenzo
River; populations in tributaries to San Francisco
Bay, excluding the Sacramento–San Joaquin River
system; and four artificial propagation programs.
Unlikely
This species is known to occur within the San
Lorenzo River and its tributaries in Santa Cruz
County but is not known to occur in other water
bodies.
Oncorhynchus mykiss irideus
Steelhead
(central California coast DPS)
FT / -- / -- Coastal perennial and near perennial streams, with suitable spawning and rearing habitat and no major
barriers.
High
This species is known to occur within Soquel Creek.
Oncorhynchus mykiss irideus
Steelhead
(south-central California coast
DPS)
FT / -- / -- Cold headwaters, creeks, and small to large rivers and lakes; anadromous in coastal streams.
Unlikely
This species is known to occur within the Pajaro
River and its tributaries in Santa Cruz County but is
not known to occur in other water bodies.
Thaleichthys pacificus
Eulachon
FT / -- / -- Occur in nearshore ocean waters and to 1,000 feet in depth, except for the brief spawning runs into
their natal streams. Spawning grounds are typically
in the lower reaches of larger snowmelt-fed rivers
with water temperatures ranging from 39 to 50°F.
Spawning occurs over sand or coarse gravel
substrates.
Low
Soquel Creek provides a suitable habitat for this
species. There is one CNDDB occurrence (#10) of
this species within the quadrangles reviewed which
encompasses the entirety of the survey area,
consisting of a historic occurrence of the species in
Soquel Lagoon estimated around 1911; however, this
species has not been documented in the vicinity
since.
INVERTEBRATES
Bombus crotchii
Crotch bumble bee
-- / SC / -- Occurs in open grassland and scrubs at relatively warm and dry sites. Requires plants that bloom and
provide adequate nectar and pollen throughout the
colony’s life cycle, which is from early February to
late October. Generally, nests underground, often in
abandoned mammal burrows. Within California this
species is known to occur in the Mediterranean,
Pacific Coast, Western Desert, as well as Great
Valley and adjacent foothill regions.
Unlikely
No suitable habitat is present within the survey area.
430
Item 9 A.
Stockton Bridge Debris Project Special-Status Species Table Species Status
(Service/CDFW/CNPS) General Habitat Potential Occurrence within Survey Area Bombus occidentalis
Western bumble bee
-- / SC / -- Occurs in open grassy areas, urban parks, urban gardens, chaparral, and meadows. This species
generally nest underground. Western bumble bee
populations are currently largely restricted to high
elevation sites in the Sierra Nevada.
Unlikely
No suitable habitat is present within the survey area.
Cicindela ohlone
Ohlone tiger beetle
FE / -- / -- Coastal terraces with remnant stands of open native grassland with clay or sandy soils. Hunt, breed, and
dig small vertical burrows along sunny single-track
trails and dirt roads (maintained by cattle, hikers,
etc.) in coast terrace meadows that still support
native grasses. Current range from the City of
Scotts Valley to the eastern edge of the City of
Santa Cruz.
Unlikely
No suitable habitat is present within the survey area
and the survey area is outside of the known range of
this species.
Danaus plexippus
Monarch butterfly
FC / -- / -- Overwinters in coastal California using colonial roosts generally found in Eucalyptus, pine and
acacia trees. Overwintering habitat for this species
within the Coastal Zone represents ESHA. Local
ordinances often protect this species as well.
Unlikely
No suitable habitat is present within the survey area
and no overwintering populations have been
documented within the survey area.
Euphilotes enoptes smithi
Smith’s blue butterfly
FE / -- / -- Most commonly associated with coastal dunes and coastal sage scrub plant communities in Monterey
and Santa Cruz Counties. Plant hosts are
Eriogonum latifolium and E. parvifolium.
Not Present
No suitable habitat is present within the survey area.
The host plant species were not identified during the
survey.
Polyphylla barbata
Mount Hermon (=barbate) June
beetle
FE / -- / -- Ponderosa pine-chaparral habitat with sandy soil and open, sparsely vegetated areas. May also occur
in more vegetated areas of chaparral. While not
always present, silver-leaved manzanita is often an
indicator of suitable habitat. Restricted to the
Zayante sandhills habitat of the Ben LomondMount Harmon-Scotts Valley area.
Unlikely
No suitable habitat is present within the survey area
and the survey area is outside of the known range of
this species.
Trimerotropis infantillis
Zayante band-winged grasshopper
FE / -- / -- Open sandy areas with sparse, low annual and perennial herbs on high ridges with sparse
ponderosa pine. Often occurs with Ben Lomond
wallflower. Restricted to sand parkland habitat
found on ridges and hills within the Zayante
sandhills habitat in Santa Cruz County. Flight
season extends from late May through August.
Unlikely
No suitable habitat is present within the survey area
and the survey area is outside of the known range of
this species.
PLANTS
Agrostis blasdalei
Blasdale’s bent grass
-- / -- / 1B Coastal bluff scrub, coastal dunes, and coastal prairie at elevations from 0-150 meters. Perennial
rhizomatous herb in the Poaceae family; blooms
May–July.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
431
Item 9 A.
Stockton Bridge Debris Project Special-Status Species Table Species Status
(Service/CDFW/CNPS) General Habitat Potential Occurrence within Survey Area Amsinckia lunaris
Bent-flowered fiddleneck
-- / -- / 1B Coastal bluff scrub, cismontane woodland, and valley and foothill grassland at elevations of 3-500
meters. Annual herb in the Boraginaceae family;
blooms March-June.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Aphyllon robbinsii
Robbin’s broomrape
-- / -- / 1B Sandy or loose soils of coastal bluffs at elevations of less than 100 meters. Annual herb in the
Orobanchaceae family; blooms April-June.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Arctostaphylos andersonii
Anderson’s manzanita
-- / -- / 1B Openings and edges of broadleaved upland forest, chaparral, and north coast coniferous forest at
elevations of 60-760 meters. Evergreen shrub in the
Ericaceae family; blooms November-May.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Arctostaphylos hookeri ssp. hookeri
Hooker’s manzanita
-- / -- / 1B Closed-cone coniferous forest, chaparral,
cismontane woodland, and coastal scrub on sandy
soils at elevations of 85-536 meters. Evergreen
shrub in the Ericaceae family; blooms January-June.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Arctostaphylos pajaroensis
Pajaro manzanita
-- / -- / 1B Chaparral on sandy soils at elevations of 30-760 meters. Evergreen shrub in the Ericaceae family;
blooms December-March.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Arctostaphylos silvicola
Bonny Doon manzanita
-- / -- / 1B Chaparral, closed-cone coniferous forest, and lower montane coniferous forest on inland marine sands at
elevations of 120-600 meters. Evergreen shrub in
the Ericaceae family; blooms February-March.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Arenaria paludicola
Marsh sandwort
FE / SE / 1B Known from only two natural occurrences in Black Lake Canyon and at Oso Flaco Lake. Sandy
openings of freshwater of brackish marshes and
swamps at elevations of 3-170 meters. Stoloniferous
perennial herb in the Caryophyllaceae family;
blooms May-August.
Not Present
No suitable habitat is present within the survey area.
The project site is outside of the accepted range of
this species.
Astragalus agnicidus
Humbolt milk vetch
-- / SE / 1B Broadleaved upland forest and North Coast
coniferous forest in disturbed/open areas and
roadsides at elevations of 120-800 meters. Perennial
herb in the Fabaceae family; blooms AprilSeptember.
Not Present
No suitable habitat is present within the survey area.
The project site is outside of the accepted range of
this species.
Calyptridium parryi var. hesseae
Santa Cruz Mountains pussypaws
-- / -- / 1B Sandy or gravelly openings of chaparral and cismontane woodlands at elevations of 305-1530
meters. Annual herb in the Montiaceae family;
blooms May-August.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
432
Item 9 A.
Stockton Bridge Debris Project Special-Status Species Table Species Status
(Service/CDFW/CNPS) General Habitat Potential Occurrence within Survey Area Carex comosa
Bristly sedge
-- / -- / 2B Coastal prairie, marshes and swamps on lake margins, and valley and foothill grassland at
elevations of 0-625 meters. Perennial rhizomatous
herb in the Cyperaceae family; blooms MaySeptember.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Carex saliniformis
Deceiving sedge
-- / -- / 1B Mesic areas of coastal prairie, coastal scrub, meadows and seeps, and coastal salt marshes and
swamps at elevations of 3-230 meters. Perennial
rhizomatous herb in the Cyperaceae family; blooms
June-July.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Ceanothus ferrisiae
Coyote ceanothus
FE / -- / 1B Chaparral, coastal scrub, and valley and foothill grassland on serpentinite soils, at elevations of 120-
460 meters. Perennial evergreen shrub in the
Rhamnaceae family; blooms January-May.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Centromadia parryi ssp. congdonii
Congdon’s tarplant
-- / -- / 1B Valley and foothill grassland on heavy clay, saline, or alkaline soils at elevations of 0-230 meters.
Annual herb in the Asteraceae family; blooms MayNovember.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Chorizanthe pungens var. pungens
Monterey spineflower
FT / -- / 1B Maritime chaparral, cismontane woodland, coastal dunes, coastal scrub, and valley and foothill
grassland on sandy soils at elevations of 3-450
meters. Annual herb in the Polygonaceae family;
blooms April-July.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Chorizanthe robusta var. hartwegii
Scott’s Valley spineflower
FE / -- / 1B Meadows and seeps on sandy soils and valley and foothill grassland on mudstone and Purisima
outcrops at elevations of 230-245 meters. Annual
herb in the Polygonaceae family; blooms AprilJuly.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Chorizanthe robusta var. robusta
Robust spineflower
FE / -- / 1B Openings in cismontane woodland, coastal dunes, maritime chaparral, and coastal scrub on sandy or
gravelly soils at elevations of 3-300 meters. Annual
herb in the Polygonaceae family; blooms AprilSeptember.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Collinsia multicolor
San Francisco collinsia
-- / -- / 1B Closed-cone coniferous forest and coastal scrub, sometimes on serpentinite soils, at elevations of 30-
250 meters. Annual herb in the Plantaginaceae
family; blooms March-May.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Dacryophyllum falcifolium
Tear drop moss
-- / -- / 1B North coast coniferous forests on carbonate soils at elevations of 50-275 meters. Moss. Known only in
Monterey and Santa Cruz counties.
Unlikely
No suitable habitat is present within the survey area
and the survey area is outside the elevational range of this species.
433
Item 9 A.
Stockton Bridge Debris Project Special-Status Species Table Species Status
(Service/CDFW/CNPS) General Habitat Potential Occurrence within Survey Area Eastwoodiella californica
Swamp harebell
-- / -- / 1B Bogs and fens, closed cone coniferous forest, coastal prairie, meadows and seeps, and freshwater
marshes and swamps at elevations of 1-405 meters.
Perennial rhizomatous herb in the Campanulaceae
family; blooms June-October.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Eriogonum nudum var. decurrens
Ben Lomond buckwheat
-- / -- / 1B Chaparral, cismontane woodland, and lower
montane coniferous forest (maritime ponderosa pine
sandhills) on sandy soils, at elevations of 50-800
meters. Perennial herb in the Polygonaceae family;
blooms June-October.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Erysimum ammophilum
Sand-loving wallflower
-- / -- / 1B Openings in maritime chaparral, coastal dunes, and coastal scrub on sandy soils at elevations of 0-60
meters. Perennial herb in the Brassicaceae family;
blooms February-June.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Erysimum teretifolium
Santa Cruz wallflower
FE / SE / 1B Chaparral and lower montane coniferous forest on inland marine sands, at elevations of 120-610
meters. Perennial herb in the Brassicaceae family;
blooms March-July.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Fissidens pauperculus
Minute pocket moss
-- / -- / 1B North coast coniferous forest on damp coastal soil at elevations of 10-1024 meters. Moss in the
Fissidentaceae family.
Unlikely
No suitable habitat is present within the survey area.
Gilia tenuiflora ssp. arenaria
Monterey gilia
FE / ST / 1B Openings in maritime chaparral, cismontane woodland, coastal dunes, and coastal scrub on
sandy soils at elevations of 0-45 meters. Annual
herb in the Polemoniaceae family; blooms AprilJune.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Hesperocyparis abramsiana var.
abramsiana
Santa Cruz cypress
FT / SE / 1B Closed-cone coniferous forest, chaparral, and lower montane coniferous forest on sandstone or granitic
soils at elevations of 280-800 meters. Evergreen
tree in the Cupressaceae family.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Hoita strobilina
Loma Prieta hoita
-- / -- / 1B Mesic areas of chaparral, cismontane woodland, and riparian woodland, usually on serpentinite soils,
at elevations of 30-860 meters. Perennial herb in the
Fabaceae family; blooms May-October.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Holocarpha macradenia
Santa Cruz tarplant
FT / SE / 1B Coastal prairies and valley foothill grasslands, often clay or sandy soils, at elevations of 10-220 meters.
Annual herb in the Asteraceae family; blooms JuneOctober.
Unlikely
No suitable habitat is present within the survey area.
Horkelia cuneata var. sericea
Kellogg’s horkelia
-- / -- / 1B Openings of closed-cone coniferous forests, maritime chaparral, coastal dunes, and coastal scrub
on sandy or gravelly soils at elevations of 10-200
meters. Perennial herb in the Rosaceae family;
blooms April-September.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
434
Item 9 A.
Stockton Bridge Debris Project Special-Status Species Table Species Status
(Service/CDFW/CNPS) General Habitat Potential Occurrence within Survey Area Horkelia marinensis
Point Reyes horkelia
-- / -- / 1B Coastal dunes, coastal prairie, and coastal scrub on sandy soils at elevations of 5-350 meters. Perennial
herb in the Rosaceae family; blooms MaySeptember.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Lasthenia californica ssp.
macrantha
Perennial goldfields
-- / -- / 1B Coastal bluff scrub, coastal dunes, and coastal scrub at an elevation of 5-520 meters. Perennial herb in
the Asteraceae family. Blooms January-November.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Lessingia micradenia var. glabrata
Smooth lessingia
-- / -- / 1B Chaparral and cismontane woodlands on
serpentinite soils, often on roadsides, at elevations
of 120-420 meters. Annual herb in the Asteraceae
family; blooms July-November.
Unlikely
No suitable habitat is present within the survey area.
Lupinus constancei
Lassics lupine
FE / SE / 1B Lower montane coniferous forest, associated with serpentine soils at elevations of 1500-2000 meters.
This species is restricted to Humboldt and Trinity
Counties within the Six Rivers National Forest.
Perennial herb in the Fabaceae family; blooms July.
Not Present
No suitable habitat is present within the survey area
and the survey area is outside the elevational range
for this species.
Malacothamnus arcuatus
Arcuate bush-mallow
-- / -- / 1B Chaparral and cismontane woodland at elevations of 15-355 meters. Perennial evergreen shrub in the
Malvaceae family; blooms April-September.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Malacothamnus hallii
Hall’s bush mallow
-- / -- / 1B Chaparral and coastal scrub at elevations of 10-760 meters. Perennial evergreen shrub in the Malvaceae
family; blooms May-October.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Microseris paludosa
Marsh microseris
-- / -- / 1B Closed-cone coniferous forest, cismontane
woodland, coastal scrub, and valley and foothill
grassland at elevations of 5-300 meters. Perennial
herb in the Asteraceae family; blooms April-July.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Monardella sinuata ssp. nigrescens
Northern curly-leaved monardella
-- / -- / 1B Chaparral, coastal dunes, coastal scrub, and lower montane coniferous forest (ponderosa pine
sandhills) on sandy soils at elevations of 0-300
meters. Annual herb in the Lamiaceae family;
blooms April-September.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Monolopia gracilens
Woodland wollythreads
-- / -- / 1B Openings of broadleaved upland forest, chaparral, cismontane woodland, North Coast coniferous
forest, and valley and foothill grassland on
serpentinite soils at elevations of 100-1200 meters.
Annual herb in the Asteraceae family; blooms
February-July.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
435
Item 9 A.
Stockton Bridge Debris Project Special-Status Species Table Species Status
(Service/CDFW/CNPS) General Habitat Potential Occurrence within Survey Area Pedicularis dudleyi
Dudley’s lousewort
-- / SR / 1B Maritime chaparral, cismontane woodland, North Coast coniferous forest, and valley and foothill
grassland at elevations of 60-900 meters. Perennial
herb in the Orbanchaceae family; blooms AprilJune.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Penstemon rattanii var. kleei
Santa Cruz Mountains beardtongue
-- / -- / 1B Chaparral and lower montane and North Coast coniferous forests at elevations of 400-1100 meters.
Perennial herb in the Plantaginaceae family; blooms
May-June.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Pentachaeta bellidiflora
White-rayed pentachaeta
FE / SE / 1B Cismontane woodland and valley and foothill grasslands, often on serpentinite soils, at elevations
of 35-620 meters. Annual herb in the Asteraceae
family; blooms March-May.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Piperia candida
White-flowered rein orchid
-- / -- / 1B Broadleaved upland forest, lower montane
coniferous forest, and North Coast coniferous
forest, sometimes on serpentinite soils, at elevations
of 30-1310 meters. Perennial herb in the
Orchidaceae family; blooms May-September.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Plagiobothrys chorisianus var.
chorisianus
Choris’ popcorn-flower
-- / -- / 1B Mesic areas of chaparral, coastal prairie, and coastal scrub at elevations of 15-160 meters. Annual herb
in the Boraginaceae family; blooms March-June.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Plagiobothrys diffusus
San Francisco popcorn-flower
-- / SE / 1B Coastal prairie and valley and foothill grassland at elevations of 60-360 meters. Annual herb in the
Boraginaceae family; blooms March-June.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Polygonum hickmanii
Scotts Valley polygonum
FE / SE / 1B Valley and foothill grassland on mudstone and sandstone at elevations of 210-250 meters. Annual
herb in the Polygonaceae family; blooms: MayAugust.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Senecio aphanactis
Chaparral ragwort
-- / -- / 2B Chaparral, cismontane woodland, and coastal scrub, sometimes on alkaline soils, at elevations of 15-800
meters. Annual herb in the Asteraceae family;
blooms January-April.
Unlikely
No suitable habitat is present within the survey area.
Sidalcea malachroides
Maple-leaved checkerbloom
-- / -- / 4 Broadleaved upland forest, coastal prairie, coastal scrub, North Coast coniferous forest, and riparian
woodlands, often in disturbed areas, at elevations of
2-730 meters. Perennial herb in the Malvaceae
family; blooms March-August.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
436
Item 9 A.
Stockton Bridge Debris Project Special-Status Species Table Species Status
(Service/CDFW/CNPS) General Habitat Potential Occurrence within Survey Area Stebbinsoseris decipiens
Santa Cruz microseris
-- / -- / 1B Broadleaved upland forest, closed-cone coniferous forest, chaparral, coastal prairie, coastal scrub, and
openings in valley and foothill grassland,
sometimes on serpentinite, at elevations of 10-500
meters. Annual herb in the Asteraceae family;
blooms April-May.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Trifolium buckwestiorum
Santa Cruz clover
-- / -- / 1B Gravelly margins of broadleaved upland forest, cismontane woodland, and coastal prairie at
elevations of 105-610 meters. Annual herb in the
Fabaceae family; blooms April-October.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
Trifolium polyodon
Pacific Grove clover
-- / SR / 1B Mesic areas of closed-cone coniferous forest, coastal prairie, meadows and seeps, and valley and
foothill grassland at elevations of 5-120 meters.
Annual herb in the Fabaceae family; blooms AprilJuly.
Not Present
No suitable habitat is present within the survey area
and this species was not identified during the May
2024 survey.
STATUS DEFINITIONS
Federal
FE = listed as Endangered under the federal Endangered Species Act FT = listed as Threatened under the federal Endangered Species Act FC = Candidate for listing under the federal Endangered Species Act UR = Species that have been petitioned for listing under the ESA and for which a 90 day and/or 12 Month finding has not been published in the Federal Register, as well as species being reviewed through the candidate process but the CNOR has not yet been signed -- = no listing
State
SE = listed as Endangered under the California Endangered Species Act ST = listed as Threatened under the California Endangered Species Act SC = Candidate for listing under California Endangered Species Act SR = listed as Rare under the California Endangered Species Act CFP = California Fully Protected Species
CSC = CDFW Species of Concern
-- = no listing
California Native Plant Society
1B = California Rare Plant Rank 1B species; plants rare, threatened, or endangered in California and elsewhere 2B = California Rare Plant Rank 2B species; plants rare, threatened, or endangered in California, but more common elsewhere -- = no listing
POTENTIAL TO OCCUR
Present = known occurrence of species within the site; presence of suitable habitat conditions; or observed during field surveys High = known occurrence of species in the vicinity from the CNDDB or other documentation; presence of suitable habitat conditions Moderate = known occurrence of species in the vicinity from the CNDDB or other documentation; presence of marginal habitat conditions within the site Low = species known to occur in the vicinity from the CNDDB or other documentation; lack of suitable habitat or poor quality 437
Item 9 A.
Stockton Bridge Debris Project Special-Status Species Table Unlikely = species not known to occur in the vicinity from the CNDDB or other documentation, no suitable habitat is present within the site Not Present = species was not observed during surveys
438
Item 9 A.
Attachment D: Site Photos
439
Item 9 A.
Stockton Bridge Debris Mitigation Project Site Photos Attachment D
Photo 2. OHWM on the south pier of Stockton Bridge (5/14/2024).
Photo 1. Close Up Photo of OWHM on the south pier of Stockton Bridge (5/14/2024). 440
Item 9 A.
Stockton Bridge Debris Mitigation Project Site Photos Attachment D
Photo 4. Swallow nests observed on the underside of Stockton Bridge deck Photo 3. OHWM on the north pier of Stockton Bridge (5/14/2024). 441
Item 9 A.
Stockton Avenue Bridge – Bridge Pier Debris Mitigation Feasibility Report CSWST2 |
Appendix E – Stockton Avenue Bridge at Soquel Creek (Bridge No. 36C0110) Storm Debris Diversions – Structural Evaluation
442
Item 9 A.
MEMORANDUM
TO: Julia Harberson, PE, Project Manager
CSW/ST2
Date: June 27, 2024
Job No: 2024083
FROM: Thomas L. Swayze, SE
Biggs Cardosa Associates, Inc.
SUBJECT: Stockton Avenue Bridge at Soquel Creek (Bridge No. 36C0110) Storm Debris Diversions
Capitola, California
Structural Evaluation
EXECUTIVE SUMMARY
The City of Capitola has suffered an ongoing seasonal accumulation of storm debris at the Stockton Avenue Bridge (Br. No. 36C0110). The City has requested to have the existing Stockton Avenue Bridge evaluated for the potential augmentation with various storm debris diversion systems.
CSW/ST2 has been contracted by the City to provide alternatives for installation of measures to prevent storm debris accumulation at the Stockton Avenue Bridge. Biggs Cardosa is providing structural commentary and support for the development of these measures.
The following documents were provided for our review:
• Structural Plans Sheets 1-4 Capitola Bridge over Soquel Creek, dated October 23,1933
• Caltrans Bridge Inspection Reports, dated May 8, 2022, September 17, 2021, September 25,2019, September 1, 2015, September 9, 2013, October 5, 2011, October 1, 2009, May 8, 2007, May 25, 2005, May 7, 2003, May 2, 2001, and August 10, 1999,
• Caltrans Summary Load Rating Sheet dated September 3, 2019 • Emergency Coastal Development Permit from the California Coastal Commission, Emergency CDP G-3-23-0065 (Stockton Avenue Bridge, dated October 2, 2023 • City of Capitola Special Provisions and Plans for Construction of Capitola Bridge over Soquel Creek (Stockton Bridge) Repairs, Federal Project No. ER-15J7(85), dated December 5, 2023
443
Item 9 A.
Stockton Avenue Bridge
Storm Debris Diversions
The Stockton Avenue Bridge is a cast-in-place concrete continuous 3-span parabolically arched box girder structure with mild reinforcement. The span configuration is an 85-foot center span with two 25-foot cantilevered end spans and two 15-foot-long bin abutments. The two end spans are cantilevered from the concrete piers in Soquel Creek (see Figure 1 for superstructure span configuration) and are separated from a bin abutment at each end. The piers are supported on reinforced concrete pile caps and timber piles. Timber piles at the piers are a combination of vertical piles and longitudinally battered piles. The existing traveled way between curbs is 30 feet.
Figure 1: Upstream Elevation from As-builts
The existing bridge, being supported on the timber piles, as shown on the plans, indicates that all existing piles are installed vertically, with battered piles in the longitudinal direction.
Battered piles are used as a method to provide lateral resistance. If existing wood piles at the creek piers are battered transversely, perhaps as an undocumented late design revision, they could present a construction obstacle for new piles adjacent to the existing piers.
The storms of January 2023 caused a portion of the slope protection and sidewalk at the abutments to crack and potentially collapse into Soquel Creek. The plans developed later that year indicate a repair of the abutment walkway cracking and patching of concrete spalls on the pier walls. Some of those spalls were noted in previous bridge inspection reports. Although the bid documents were issued in October 2023, we have not confirmed if that construction has taken place since cracking was observed in the walkway slab beneath the south abutment. 444
Item 9 A.
Stockton Avenue Bridge
Storm Debris Diversions
CSW/ST2 was contracted by the City to provide alternatives for installation of measures to prevent storm debris accumulation at the Stockton Avenue Bridge. CSW/ST2 has developed five alternatives for consideration:
Alternative 1: Reinforced concrete fin walls upstream at piers Alternative 2: Structural steel debris cages upstream at piers Alternative 3: Extended pile poles in triangular layout upstream at piers Alternative 4: Pre-manufactured floating debris sweeper upstream at piers Alternative 5: Bridge Replacement
All the above alternatives are based on the use of driven cast-in-place steel shell piles in varying configurations.
Biggs Cardosa performed a site visit on March 18, 2024, to observe the existing site conditions.
Based on the photos taken at the time and a review of existing documents, we believe that all options are feasible from a structural perspective. Our structural commentary follows:
ALTERNATIVES
It should be noted that all the alternatives considered above include the installation of piles in Soquel Creek which will require construction operations over the water. Performing this work will require several preparatory steps for operations, permitting, and construction considerations. Some issues that will need to be addressed are:
• Biological and Archeological Studies
• Agency permits based on findings
o Army Corps of Engineers
o Regional Water Quality Control Board
o California Department of Fish and Wildlife
o US Fish and Wildlife
o Possibly Caltrans depending on funding sources
• Construction work windows in the channel (potential multi-year) • Historical structure impacts of proposed construction Alternative 1: Reinforced Concrete Fin Walls upstream at piers Tapered concrete fin walls supported on large diameter cast-in-steel shells with interlocking grade beams. Fin walls are proposed to be independent from the existing bridge and cantilevered from the large diameter piles for out-of-plane seismic forces. This alternative is feasible to construct in a single season. More discussion is merited about the possibility of transversely battered timber piles.
445
Item 9 A.
Stockton Avenue Bridge
Storm Debris Diversions
Alternative 2: Structural Steel Debris Cages upstream at piers Structural steel debris cages supported on large diameter cast-in-steel shells with interlocking grade beams. Debris cages are proposed to be independent from the existing bridge and cantilevered from the large diameter piles for out-of-plane seismic forces. This alternative is more likely to be feasible to construct in a single season because of the ability to prefabricate the cages prior to the construction window. The possibility of transversely battered timber piles is less of a concern with this system as the pile configuration avoids likely locations for existing battered piles.
Alternative 3: Extended Pile Poles in triangular layout upstream at piers Extended pile poles supported on large diameter cast-in-steel shells with interlocking grade beams. It is likely that steel shell pile extensions or cast-in-place pole extensions may be preferable to embedded steel sections. This alternative is feasible to construct in a single season.
While this pile layout is less likely for potential pile conflicts it is not as favorable as Alternative 2.
More discussion is merited about the possibility of transversely battered timber piles.
Alternative 4: Pre-manufactured Floating Debris Sweeper upstream at piers Use of a pre-manufactured spinning debris sweeper supported on large diameter cast-in-steel shells. The debris sweeper assemblies are proposed to be independent from the existing bridge and cantilevered from a large diameter pile for operational and seismic forces. This alternative is feasible to construct in a single season as there are fewer piles and the main sweeper is prefabricated. More discussion is merited about the possibility of transversely battered timber piles. A sweeper of this type may be difficult to obtain.
Alternative 5: Bridge Replacement
The bridge replacement option is a viable option for debris mitigation as the proposed bridge structure clear spans the creek, eliminating the two piers in the water and creating a more favorable hydraulic channel. In addition, the Stockton Bridge is a critical link for emergency services / response for the coastal community. The closest alternative crossing of Soquel Creek is Highway 1. The existing bridge is 90 years old and highly likely to be seismically deficient.
The bridge sufficiency rating from Caltrans Inspection Reports is 60.6. That rating would likely qualify for rehabilitation funding assistance, but additional studies would need to be performed for replacement funding assistance. The deck rating is poor due to excessive transverse cracking, but the overall superstructure is rated as fair. No observation of the interior of the box girder was performed for these ratings. If the manhole lids were all removed, a structural observation could verify if there is any sign of interior concrete degradation that might lower the sufficiency rating.
446
Item 9 A.
Stockton Avenue Bridge
Storm Debris Diversions
The most recent Bridge Inspection Report lists the Stockton Avenue Bridge in Historic Bridge Inventory Historic Status Category 2; eligible for the office list of National Register of Historic Places (NRHP). This means that that the bridge has been determined eligible as a result of the historic bridge inventory and subsequent updates. Caltrans will need to be contacted to obtain additional information about the Historic Bridge Rating Sheet from the Office of Historic Preservation or sometimes on request from the Cultural Studies Office. There is a multi-step process through Caltrans to determine how the historic nature of the structure affects replacement and what features may be necessary for the new design.
A new replacement structure could be configured so that the new clear span structure would mimic the existing historic character of the bridge, incorporating such features as:
• Arched bridge soffit
• Historic railing Features
• Art Deco lighting support pedestals
• Art Deco approach pedestals at abutments
There are several design hurdles to overcome for the replacement option such as:
• Environmental and permitting studies
• Multi-season construction period
• Demolition and construction activities in the creek channel • Caltrans review and coordination
• Historical structure issues
• Community involvement
• Traffic handling and stage construction
• Utilities in the existing bridge
• Abutment replacements
• Bridge hydrology report
• Geotechnical borings and report
CONCLUSIONS
All of the alternatives considered are structurally feasible. Depending on additional consideration of the potential of transversely battered piles, some are preferable to others. If transversely battered piles do not exist at the piers, then Alternative 4 is likely the most economical option structurally. Alternative 3 would be another cost-effective option. If it is determined that the risk of battered piles is too high, then Alternative 2 would be the most economical option, followed by a reconfigured Alternative 3. Alternative 1 would have the most construction and cost challenges of the retrofit options. Alternative 5, the full replacement option extends the expected life span of the bridge another 75 years and eliminates the storm debris obstacles. The replacement option would be a much lengthier design and construction process as well as the costliest option.
447
Item 9 A.
Stockton Avenue Bridge – Bridge Pier Debris Mitigation Feasibility Report CSWST2 |
Appendix F – Program Level Cost Estimates
448
Item 9 A.
Stockton Avenue Bridge Debris Mitigation Measure - Debris Diversion Fin Program Level Cost Estimate
06.21.2024
UNIT
ITEM DESCRIPTION QTY. UNIT COST CONT AMOUNT
101 Mobilization/ Demobilization 1 LS $110,310 $110,310 102 Traffic Management 1 LS 56,000.00 $ 10% $61,600
103 Jobsite Fencing and Gates on Land 100 LF $ 25% $6,250 50.00 104 Jobsite Fencing in Water/On Cofferdam 200 LF $ 25% $18,750 75.00 105 Bridge Protection 30 LF $ 25% $18,750 500.00
106 Water Pollution Control Plan 1 LS 15,000.00 $ 10% $16,500 107 Construction Layout 1 LS 20,000.00 $ 10% $22,000
108 Environmental Monitoring 1 LS 70,000.00 $ 10% $77,000 109 Coffer Dam 2 EA $ 70,000.00 25% $175,000
110 Dewatering 1 LS $ 60,000.00 25% $75,000
111 Access Bridges and Scaffolding 1 LS $ 150,000.00 25% $187,500 112 Concrete Formwork 1,120 SF $ 15.00 25% $21,000
113 Reinforced Concrete Footing 120 SF 425.00 $ 25% $63,750 114 Reinforced Concrete Fin Wall 280 SF $ 25% $122,500 350.00 115 Reinforced Concrete Pier 8 EA 20,000.00 $ 25% $200,000 116 Pump House Removal 1 LS 30,000.00 $ 25% $37,500
$1,213,000
Notes
$100,000
$37,843
$181,950
$1,532,793
$1,640,000
3. Assumes 25' Pier length. $1,755,000
Prepared by: J Harberson
Checked by : K Pillsbury CLASS 5 ESTIMATE
Planning and CEQA
Total Construction Cost:
Recommended Budget $1,600,000 to $1,800,000
Final Design
Construction Management
Total Cost (2024 Dollars)
Total Cost (2025 Dollars)
Total Cost (2026 Dollars)
Assumes two (2) debris fins installed
over a construction period of 30 days.
1. Assumes height of fin walls is 14' tall and
12" width. 2.
449
Item 9 A.
1 inch = 10 ft.
10 8.6±'
ANGLE FIN TO MINIMIZE
DEBRIS CATCH BETWEENPIER AND CREEK WALL.
SOQUEL CREEK
FLOW DIRECTION
CREEK WALL CREEK WALL
EDGE EXISTINGBRIDGE DECK
EDGE EXISTINGBRIDGE DECK
SOQUEL CREEK
FLOW DIRECTION
TO PACIFIC OCEAN
CREEK WALL CREEK WALL
FACE OF
ABUTMENT
UNDER BRIDGE
FACE OF
ABUTMENT
UNDER BRIDGE
CREEK WALLCONTINUES
UNDER BRIDGE
PIERUNDER BRIDGE
S T O C K T O N A V E
PIERUNDER BRIDGE
91.3±'
79.8±'
26.0±'
2 0
'
20'
FOOTING, TYP.
FIN, TYP.
PIER, TYP.
22.4±'
100±LF COFFERDAM
100±LF COFFERDAM
10±LF BRIDGE PROTECTION + COFFERDAM 10±LF BRIDGE PROTECTION + COFFERDAM BRIDGE.
GAP IS ABOUT 2'
AS SHOWN
STAIRS ANDSCAFFOLDING
INSIDE
STAIRS ANDSCAFFOLDING
INSIDE
BRIDGE.
GAP IS ABOUT 15'ON WIDE SIDE
AS SHOWN
FENCING INTEGRAL
WITH COFFERDAM
30±LF
FENCING
AND GATE
GATE
55±LF
FENCING
AND GATE
ON LAND
75±LF
FENCING INTEGRAL
WITH COFFERDAM
10±LF
WALL PROTECTION + COFFERDAM
85'
CENTERLINE PIER TO CENTERLINE PIER
&
CENTERLINE END FIN TO CENTERLINE END FIN PIER UNDER
BRIDGE
PIER UNDERBRIDGE
FACE OF
ABUTMENT
UNDER BRIDGE
FACE OF
ABUTMENT
UNDER BRIDGE
APPROXIMATE LOCATION
OF EXISTING CREEK WALL
UNDER BRIDGE
REINFORCED
CONCRETE PIER, TYP.
REINFORCED
CONCRETE
FOOTING, TYP.
REINFORCED
CONCRETE
FIN WALL, TYP.
ANGLE FIN TO MINIMIZE
DEBRIS CATCH BETWEENPIER AND CREEK WALL.
EXISTING
TIMBER PILES, TYP.
25' 25'
PIER FOOTING,
TYP.
20'
PIER UNDERBRIDGE
REINFORCED
CONCRETE PIER, TYP.
REINFORCED
CONCRETE
FOOTING, TYP.
REINFORCED
CONCRETE
FIN WALL, TYP.
EXISTING
TIMBER PILES, TYP.
(DIAGRAMMATICALLY
SHOWN)
CONCRETE FIN
WALL AND FOUNDATION
BEYOND IN DASHED, TYP..
PIER FOOTING
SOQUEL CREEK
FLOW DIRECTION
APPROXIMATE
CREEK BOTTOM
SDA1
DEBRIS DIVERSION FIN - XX/XX/XX XXX XXX XXX XXX 1" = X' P:\Shared\Projects\2023\2300338 Capitola Stockton Bridge Replacement\DWG\Exhibits\Cost Estimate Exhibits.dwg 06/21/2024 - 01:24 PM nankk 1:1 Sheet Plan File: Project Number: 2300338 Prepared Under the Direction of: CITY OF CAPITOLA STOCKTON AVENUE BRIDGE MITIGATION State County City California Santa Cruz Capitola
Rev Date Description Designed Drawn Checked
Scale:
Date: 04/18/2024
303 TWIN DOLPHIN DRIVE
REDWOOD CITY, CA 94065
©2024
ENGINEERING | LANDSCAPE ARCHITECTURE
SURVEYING | URBAN PLANNING
415.883.9850
WWW.CSWST2.COM
SCHEMATIC DESIGN ALTERNATIVE
PLAN
UPSTREAM ELEVATION WESTWARD ELEVATION
SCALE: 1"=10'SCALE: 1"=10' SCALE: 1"=10'
450
Item 9 A.
Stockton Avenue Bridge Debris Mitigation Measure - Debris Diversion Cage Program Level Cost Estimate
06.21.2024
UNIT
ITEM DESCRIPTION QTY. UNIT COST CONT AMOUNT
101 Mobilization/ Demobilization 1 LS $97,440 $97,440
102 Traffic Management 1 LS 46,500.00 $ 10% $51,150
103 Jobsite Fencing and Gates on Land 100 LF $ 25% $6,250 50.00 104 Jobsite Fencing in Water/On Cofferdam 200 LF $ 25% $18,750 75.00 105 Bridge Protection 30 LF $ 25% $18,750 500.00
106 Water Pollution Control Plan 1 LS 15,000.00 $ 10% $16,500 107 Construction Layout 1 LS 20,000.00 $ 10% $22,000
108 Environmental Monitoring 1 LS 60,000.00 $ 10% $66,000 109 Coffer Dam 2 EA $ 70,000.00 25% $175,000
110 Dewatering 1 LS $ 60,000.00 25% $75,000
111 Access Bridges and Scaffolding 1 LS $ 150,000.00 25% $187,500 112 Debris Diversion Cage 2 EA 60,000.00$ 25% $150,000
113 Reinforced Concrete Pier 6 EA 20,000.00 $ 25% $150,000 114 Pump House Removal 1 LS 30,000.00 $ 25% $37,500
$1,072,000
Notes
$100,000
$37,843
$160,800
2. Assumes 25' Pier length. $1,370,643
$1,467,000
$1,570,000
Prepared by: J Harberson
Checked by : K Pillsbury CLASS 5 ESTIMATE
Planning and CEQA
Total Construction Cost:
Recommended Budget $1,400,000 to $1,600,000
Final Design
Construction Management
Total Cost (2024 Dollars)
Total Cost (2025 Dollars)
Total Cost (2026 Dollars)
Assumes two (2) debris cages installed
over a construction period of 25 days.
1. 451
Item 9 A.
1 inch = 10 ft.
10 76±'
S T O C K T O N A V E
SOQUEL CREEK
FLOW DIRECTION
CREEK WALL CREEK WALL
EDGE EXISTING BRIDGE DECK
EDGE EXISTINGBRIDGE DECK
SOQUEL CREEK
FLOW DIRECTION
TO PACIFIC OCEAN
CREEK WALL CREEK WALL
FACE OF
ABUTMENT
UNDER BRIDGE
FACE OF
ABUTMENT
UNDER BRIDGE
CREEK WALLCONTINUES
UNDER BRIDGE
PIERUNDER BRIDGE
PIERUNDER BRIDGE
7 84.5±' .8±' 26.9±'
8.9'
TYP.
2 3
.
8 ±
'
T
Y
P
.
DEBRIS DEFLECTOR CAGE FRAME, TYP.
6.6±' 20.8±'
25' 85' 25'
105±LF COFFERDAM
100±LF COFFERDAM
10±LF BRIDGE PROTECTION + COFFERDAM 10±LF BRIDGE PROTECTION + COFFERDAM BRIDGE.
GAP IS ABOUT 2'
AS SHOWN STAIRS AND
SCAFFOLDING
INSIDE
STAIRS ANDSCAFFOLDING
INSIDE
BRIDGE.
GAP IS ABOUT 15'ON WIDE SIDE
AS SHOWN
FENCING INTEGRAL
WITH COFFERDAM
30±LF
FENCING
AND GATE
GATE
50±LF
FENCING
AND GATE
ON LAND
85±LF
FENCING INTEGRAL
WITH COFFERDAM
85'
CENTERLINE PIER TO CENTERLINE PIER
&
CENTERLINE DEBRIS CAGE TO CENTERLINE DEBRIS CAGE PIER UNDER BRIDGE PIER UNDER BRIDGE
FACE OF
ABUTMENT
UNDER BRIDGE
FACE OF
ABUTMENT
UNDER BRIDGE
APPROXIMATE LOCATION
OF EXISTING CREEK WALL
UNDER BRIDGE
REINFORCED
CONCRETE PIERS, TYP.
EXISTING
TIMBER PILES, TYP.
25' 25'
DEBRIS DEFLECTOR CAGE FRAME:
WELDED 6"x6" GALVANIZED
STEEL SQUARE BAR, TYP.
22.3'±
PIER UNDERBRIDGE
REINFORCED
CONCRETE PIER, TYP.
GALVANIZED STEEL
POST EMBEDDED IN
CONCRETE PIER.
EXISTING
TIMBER PILES, TYP.
(DIAGRAMMATICALLY
SHOWN)
PIER FOOTING
SOQUEL CREEK
FLOW DIRECTION
APPROXIMATE
CREEK BOTTOM
DEBRIS DEFLECTOR CAGE FRAME:
WELDED 6"x6" GALVANIZED STEEL SQUARE BAR
10.5±'
23.8±'
SDA2 - XX/XX/XX XXX XXX XXX XXX 1" = X'
P:\Shared\Projects\2023\2300338 Capitola Stockton Bridge Replacement\DWG\Exhibits\Cost Estimate Exhibits.dwg 06/21/2024 - 01:26 PM nankk 1:1 Sheet Plan File: Project Number: 2300338 Prepared Under the Direction of: CITY OF CAPITOLA STOCKTON AVENUE BRIDGE MITIGATION State County City California Santa Cruz Capitola
Rev Date Description Designed Drawn Checked
Scale:
Date: 04/18/2024
303 TWIN DOLPHIN DRIVE
REDWOOD CITY, CA 94065
©2024
ENGINEERING | LANDSCAPE ARCHITECTURE
SURVEYING | URBAN PLANNING
415.883.9850
WWW.CSWST2.COM
DEBRIS DIVERSION CAGE
SCHEMATIC DESIGN ALTERNATIVE
PLAN
UPSTREAM ELEVATION WESTWARD ELEVATION
SCALE: 1"=10'SCALE: 1"=10' SCALE: 1"=10'
452
Item 9 A.
Stockton Avenue Bridge Debris Mitigation Measure - Debris Diversion Piers Program Level Cost Estimate
06.21.2024
UNIT
ITEM DESCRIPTION QTY. UNIT COST CONT AMOUNT
101 Mobilization/ Demobilization 1 LS $149,940 $149,940 102 Traffic Management 1 LS 46,500.00 $ 10% $51,150
103 Jobsite Fencing and Gates on Land 100 LF $ 25% $6,250 50.00 104 Jobsite Fencing in Water/On Cofferdam 200 LF $ 25% $18,750 75.00 105 Bridge Protection 30 LF $ 25% $18,750 500.00
106 Water Pollution Control Plan 1 LS 15,000.00 $ 10% $16,500 107 Construction Layout 1 LS 20,000.00 $ 10% $22,000
108 Environmental Monitoring 1 LS 60,000.00 $ 10% $66,000 109 Coffer Dam 2 EA $ 70,000.00 25% $175,000
110 Dewatering 1 LS $ 60,000.00 25% $75,000
111 Access Bridges and Scaffolding 1 LS $ 150,000.00 25% $187,500 112 Steel Bollards 22 EA $ 5,000.00 25% $137,500
113 Reinforced Concrete Pier 22 EA 25,000.00$ 25% $687,500 114 Pump House Removal 1 LS 30,000.00 $ 25% $37,500
$1,649,000
Notes
$100,000
$37,843
$247,350
2. Assumes 25' Pier embedment length. $2,034,193
$2,177,000
$2,329,000
Prepared by: J Harberson
Checked by : K Pillsbury CLASS 5 ESTIMATE
Planning and CEQA
Total Construction Cost:
Recommended Budget $2,100,000 to $2,400,000
Final Design
Construction Management
Total Cost (2024 Dollars)
Total Cost (2025 Dollars)
Total Cost (2026 Dollars)
Assumes 22 debris diversion piers
installed over a construction period of
25 days.
1. Assume Concrete Filled Galvanzied Steel
Bollards.
3. 453
Item 9 A.
1 inch = 10 ft.
10 85±'
S T O C K T O N A V E
SOQUEL CREEK
FLOW DIRECTION
CREEK WALL CREEK WALL
EDGE EXISTINGBRIDGE DECK
EDGE EXISTINGBRIDGE DECK
SOQUEL CREEK
FLOW DIRECTION
TO PACIFIC OCEAN
CREEK WALL CREEK WALL
FACE OF
ABUTMENT
UNDER BRIDGE
FACE OF
ABUTMENT
UNDER BRIDGE
CREEK WALLCONTINUES
UNDER BRIDGE
PIERUNDER BRIDGE
PIERUNDER BRIDGE
7.6±' 27.0±'
FOOTING AS NEEDED, TYP.
2 5
'
±
T
YP
.
20.9±'
6.7±'
76.5±'
8.5±'
CONCRETE PIER, TYP.
GALVANIZED STEEL PIER POLE, TYP.
25' 25' 85'
105±LF COFFERDAM
100±LF COFFERDAM
10±LF BRIDGE PROTECTION + COFFERDAM 10±LF BRIDGE PROTECTION + COFFERDAM BRIDGE.
GAP IS ABOUT 2'
AS SHOWN STAIRS AND
SCAFFOLDING
INSIDE
STAIRS ANDSCAFFOLDING
INSIDE
BRIDGE.
GAP IS ABOUT 15'ON WIDE SIDE
AS SHOWN
FENCING INTEGRAL
WITH COFFERDAM
30±LF
FENCING
AND GATE
GATE
50±LF
FENCING
AND GATE
ON LAND
85±LF
FENCING INTEGRAL
WITH COFFERDAM
85'
CENTERLINE BRIDGE PIER TO CENTERLINE BRIDGE PIER
&
CENTERLINE TO CENTERLINE
OF PIER ARRANGEMENTS BRIDGE SUPPORT PIER UNDER BRIDGE BRIDGE SUPPORT PIER UNDER BRIDGE
FACE OF
ABUTMENT
UNDER BRIDGE
FACE OF
ABUTMENT
UNDER BRIDGE
APPROXIMATE LOCATION
OF EXISTING CREEK WALL
UNDER BRIDGE
REINFORCED
CONCRETE PIERS, TYP.
PIER POLESEMBEDDED IN
CONCRETE PIERS,
TYP.
GALVANIZEDSTEEL PIER POLES, TYP..
EXISTING
TIMBER PILES, TYP.
25' 25'
25'
BRIDGE SUPPORTPIER UNDERBRIDGE
REINFORCED
CONCRETE PIER, TYP.
REINFORCED
CONCRETE
FOOTING, TYP.
EXISTING
TIMBER PILES, TYP.
(DIAGRAMMATICALLY
SHOWN)
PIER FOOTING
SOQUEL CREEK
FLOW DIRECTION
APPROXIMATE
CREEK BOTTOM
SDA3 - XX/XX/XX XXX XXX XXX XXX 1" = X'
P:\Shared\Projects\2023\2300338 Capitola Stockton Bridge Replacement\DWG\Exhibits\Cost Estimate Exhibits.dwg 06/21/2024 - 01:28 PM nankk 1:1 Sheet Plan File: Project Number: 2300338 Prepared Under the Direction of: CITY OF CAPITOLA STOCKTON AVENUE BRIDGE MITIGATION State County City California Santa Cruz Capitola
Rev Date Description Designed Drawn Checked
Scale:
Date: 04/18/2024
303 TWIN DOLPHIN DRIVE
REDWOOD CITY, CA 94065
©2024
ENGINEERING | LANDSCAPE ARCHITECTURE
SURVEYING | URBAN PLANNING
415.883.9850
WWW.CSWST2.COM
DEBRIS DIVERSION PIERS
SCHEMATIC DESIGN ALTERNATIVE
PLAN
UPSTREAM ELEVATION WESTWARD ELEVATION
SCALE: 1"=10'SCALE: 1"=10' SCALE: 1"=10'
454
Item 9 A.
Stockton Avenue Bridge Debris Mitigation Measure - Debris Diversion Sweeper Program Level Cost Estimate
06.21.2024
UNIT
ITEM DESCRIPTION QTY. UNIT COST CONT AMOUNT
101 Mobilization/ Demobilization 1 LS $85,027 $85,027
102 Traffic Management 1 LS 37,200.00 $ 10% $40,920
103 Jobsite Fencing and Gates on Land 100 LF $ 25% $6,250 50.00 104 Jobsite Fencing in Water/On Cofferdam 200 LF $ 25% $18,750 75.00 105 Bridge Protection 30 LF $ 25% $18,750 500.00
106 Water Pollution Control Plan 1 LS 13,000.00 $ 10% $14,300 107 Construction Layout 1 LS 10,000.00 $ 10% $11,000
108 Environmental Monitoring 1 LS 48,000.00 $ 10% $52,800 109 Coffer Dam 2 EA $ 70,000.00 25% $175,000
110 Dewatering 1 LS $ 60,000.00 25% $75,000
111 Access Bridges and Scaffolding 1 LS $ 150,000.00 25% $187,500 112 Prefabricated Debris Sweeper 2 EA $ 60,000.00 25% $150,000 113 Reinforced Concrete Pier 2 EA 25,000.00$ 25% $62,500 114 Pump House Removal 1 LS 30,000.00 $ 25% $37,500
$935,000
Notes
$100,000
$37,843
$140,250
2. Assumes 25' Pier embedment length. $1,213,093
$1,298,000
$1,389,000
Prepared by: J Harberson
Checked by : K Pillsbury CLASS 5 ESTIMATE
Planning and CEQA
Total Construction Cost:
Recommended Budget $1,300,000 to $1,400,000
Final Design
Construction Management
Total Cost (2024 Dollars)
Total Cost (2025 Dollars)
Total Cost (2026 Dollars)
Assumes two (2) debris sweepers
installed over a construction period of
20 days.
1. 455
Item 9 A.
1 inch = 10 ft.
10 85'
S T O C K T O N A V E
SOQUEL CREEK
FLOW DIRECTION
CREEK WALL CREEK WALL
EDGE EXISTINGBRIDGE DECK
EDGE EXISTINGBRIDGE DECK
SOQUEL CREEK
FLOW DIRECTION
TO PACIFIC OCEAN
CREEK WALL CREEK WALL
FACE OF
ABUTMENT
UNDER BRIDGE
FACE OF
ABUTMENT
UNDER BRIDGE
CREEK WALLCONTINUES
UNDER BRIDGE
PIERUNDER BRIDGE
PIERUNDER BRIDGE
MANUFACTURED FLOATINGDEBRIS SWEEPER, TYP.
ESTIMATED OUTER DIAMETER: 3'
25.4±' 10.4±'
4 .
5 ±
'
90±LF COFFERDAM
85±LF COFFERDAM
10±LF BRIDGE PROTECTION + COFFERDAM 10±LF BRIDGE PROTECTION + COFFERDAM BRIDGE.
GAP IS ABOUT 2'
AS SHOWN STAIRS AND SCAFFOLDING
INSIDE
STAIRS ANDSCAFFOLDING
INSIDE
BRIDGE.
GAP IS ABOUT 15'ON WIDE SIDE
AS SHOWN
FENCING INTEGRAL
WITH COFFERDAM
30±LF
FENCING
AND GATE
GATE
50±LF
FENCING
AND GATE
ON LAND
65±LF
FENCING INTEGRAL
WITH COFFERDAM
85'
CENTERLINE EX. BRIDGE PIER TO EX. BRIDGE PIER
&
CENTERLINE SWEEPER TO CENTERLINE SWEEPER PIER UNDER
BRIDGE
PIER UNDERBRIDGE
FACE OF
ABUTMENT
UNDER BRIDGE
FACE OF
ABUTMENT
UNDER BRIDGE
APPROXIMATE LOCATION
OF EXISTING CREEK WALL
UNDER BRIDGE
REINFORCED
CONCRETE PIER, TYP.
EXISTING
TIMBER PILES, TYP.
GALVANIZED STEEL
POST EMBEDDED IN
CONCRETE PIER.
MANUFACTURED FLOATING DEBRIS SWEEPER.RISES AND FALLS WITH WATER LEVEL. 25' 25'
PIER FOOTING,
TYP.
4.5'±
PIER UNDERBRIDGE
REINFORCED
CONCRETE PIER, TYP.
GALVANIZED STEEL
POST EMBEDDED IN
CONCRETE PIER.
EXISTING
TIMBER PILES, TYP.
(DIAGRAMMATICALLY
SHOWN)
MANUFACTURED FLOATINGDEBRIS SWEEPER.
PIER FOOTING
SOQUEL CREEK
FLOW DIRECTION
APPROXIMATE
CREEK BOTTOM
SDA4 - XX/XX/XX XXX XXX XXX XXX 1" = X'
P:\Shared\Projects\2023\2300338 Capitola Stockton Bridge Replacement\DWG\Exhibits\Cost Estimate Exhibits.dwg 06/21/2024 - 01:52 PM nankk 1:1 Sheet Plan File: Project Number: 2300338 Prepared Under the Direction of: CITY OF CAPITOLA STOCKTON AVENUE BRIDGE MITIGATION State County City California Santa Cruz Capitola
Rev Date Description Designed Drawn Checked
Scale:
Date: 04/18/2024
303 TWIN DOLPHIN DRIVE
REDWOOD CITY, CA 94065
©2024
ENGINEERING | LANDSCAPE ARCHITECTURE
SURVEYING | URBAN PLANNING
415.883.9850
WWW.CSWST2.COM
DEBRIS DIVERSION SWEEPER
SCHEMATIC DESIGN ALTERNATIVE
PLAN
UPSTREAM ELEVATION WESTWARD ELEVATION
SCALE: 1"=10'SCALE: 1"=10' SCALE: 1"=10'
456
Item 9 A.
Stockton Avenue Bridge Debris Mitigation Measure - Bridge Replacement Program Level Cost Estimate
06.21.2024
UNIT
ITEM DESCRIPTION QTY. UNIT COST CONT AMOUNT
101 Mobilization/ Demobilization 1 LS $1,379,084 $1,379,084 102 Traffic Management 1 LS 260,000.00 $ 15% $299,000
103 Existing Building Protection and
Pedestrian Access to Buildings 1 LS 100,000.00 $ 15% $115,000 104 Water Pollution Control Plan 1 LS 70,000.00 $ 10% $77,000 105 Jobsite Fencing and Gates on Land 120 LF $ 25% $7,500 50.00 106 Jobsite Fencing in Water/On Cofferdam 300 LF $ 25% $28,125 75.00 105 Bridge Demolition 1 LS 200,000.00 $ 25% $250,000
106 Dewatering 1 LS 60,000.00 $ 25% $75,000
107 Access Bridges and Scaffolding 1 LS 100,000.00 $ 25% $125,000 108 Construction Layout 1 LS 50,000.00 $ 15% $57,500
109 Environmental Monitoring 1 LS 108,000.00 $ 15% $124,200 110 Bridge Decking 7,020 SF $ 25% $4,387,500 500.00
111 Bridge Abutments 2 EA 2,800,000.00 $ 25% $7,000,000 112 Coffer Dams for Bridge Abuttments 2 EA 100,000.00 $ 25% $250,000 113 Walls, Walks and Ramps for 2 Parks 1 LS 50,000.00 $ 25% $62,500 114 Offbridge Curb and Gutter 247 LF $ 10% $13,585 50.00 115 Offbridge Sidewalk 2,150 SF $ 10% $106,425 45.00
116 Lighting & Electrical Service 1 LS 150,000.00 $ 25% $187,500 117 Utilities (water, sewer, gas) 300 LF 1,000.00 $ 25% $375,000 118 Temp. Utility Bypass (water, sewer, gas) 300 LF $ 25% $187,500 500.00 119 Striping & Signage 1 LS 20,000.00 $ 25% $25,000
120 Pump House Removal 1 LS 30,000.00 $ 25% $37,500
$15,170,000
Notes
$300,000
$758,500
$1,061,900
$17,290,400
$18,501,000
$19,796,000
4. Assumes new abutments located in same location as existing.
6. Bridge Decking includes walls, curb and sidewalk.
7. Bridge Abutment includes all structural elements.
Prepared by: J Harberson
Checked by : K Pillsbury CLASS 5 ESTIMATE
Demolitions includes, cost of coffer
dams and dewatering to remove piers.
2. 3.
5. Environmental Montioring assumed to be limited to in water work and abutment demolition/construction (i.e. 45 days)
Planning and CEQA
Total Construction Cost:
Recommended Budget $17,300,000 to $19,800,000
Final Design
Construction Management
Total Cost (2024 Dollars)
Total Cost (2025 Dollars)
Total Cost (2026 Dollars)
Assumes 135' clear span bridge with a 6'
deck system, constructed over a period
of five (5) months.
1. Traffic Control Costs assume existing bridge is
demolished 1/2 at a time, the remaining half will be
utilized for one (1) lane of traffic (includes
pedestrian and bicycle traffic)
457
Item 9 A.
1 inch = 10 ft.
10 5
2 '
P
R
O
P
O
S
E
D
WID
T
H
EDGE BRIDGE DECK/
OUTSIDE EDGE OF RAIL.
MATCH EDGE OFEXISTING BRIDGE
S T O C K T O N A V E
8 '
SID
E
-
W
A
L
K
5 '
B
I
K
E
L
A
N
E
1 2
'
T
R
A
V
E
L
L
A
N
E
1 2
'
T
R
A
V
E
L
L
A
N
E
5 '
B
I
K
E
L
A
N
E
8 '
S
DI E
-
W
A
L
KEDGE DECK/ OUTSIDE
EDGE OF RAIL OFEXISTING BRIDGE.
4 4
.
1 7
'
E
XIS
TIN
G
WID
T
H
EDGE DECK/ OUTSIDEEDGE OF RAIL OFPROPOSED BRIDGE.
SOQUEL CREEK
FLOW DIRECTION
CREEK WALL CREEK WALL
SOQUEL CREEK
FLOW DIRECTION
TO PACIFIC OCEAN
CREEK WALL CREEK WALL
FACE OF
ABUTMENT
UNDER BRIDGE
FACE OF
ABUTMENT
UNDER BRIDGE
CREEK WALLCONTINUES
UNDER BRIDGE
PIERUNDER BRIDGE
(DEMO)
PIERUNDER BRIDGE
(DEMO)
4.8%
4.8%
MATCH EX
ELEVATION
MATCH EX
ELEVATION
146±LF COFFERDAM &
FENCING INTEGRAL
WITH COFFERDAM
12±LF WALL
PROTECTION
+ COFFERDAM
STAIRS
STAIRS ANDSCAFFOLDING
INSIDE
STAIRS ANDSCAFFOLDING
INSIDE
40±LF
FENCING
AND GATE
45±LF
FENCING
AND GATE
133±LF COFFERDAM &
FENCING INTEGRAL
WITH COFFERDAM
20±LF WALL
PROTECTION
+ COFFERDAM
STAIRS
20±LF WALL
PROTECTION
+ COFFERDAM
12±LF WALL
PROTECTION
+ COFFERDAM
15±LF
FENCING
20±LF FENCING
NOTE:
COFFERDAMS SHOWN ARE SCHEMATIC AND SIZED APPROXIMATELY TO
ACCOMMODATE PIER DEMOLITION, ABUTMENT DEMOLITION AND ABUTMENT CONSTRUCTION UNDER ENTIRE WIDTH OF PROPOSED BRIDGE.
EXACT CONFIGURATION IS SUBJECT TO MITIGATION AND SAFETYREQUIREMENTS, CONSTRUCTION STAGING, SCHEDULE AND CONTRACTOR'SMEANS AND METHODS. 135'±
CLEAR SPAN
REMOVE PIER UNDER BRIDGE
ABOVE FOOTING, TYP, EXISTING AND PROPOSED
FACE OF
ABUTMENT
EXISTING AND
PROPOSED
FACE OF
ABUTMENT
APPROXIMATE LOCATION
OF EXISTING CREEK WALL
UNDER BRIDGE EXISTING TIMBER PILES
TO REMAIN, TYP.
PIER FOOTING,
TO BE DETERMINED WHETHER TO
REMOVE OR TO REMAIN, TYP.
MATCH EX
PAVEMENTELEVATION
MATCH EXPAVEMENTELEVATION
EXISTING DECKELEVATION,
APPROXIMATE.
PROPOSED DECKELEVATION,
APPROXIMATE.
6'
BRIDGE SOFFIT,
APPROXIMATE.
BRIDGE RAIL /BARRIER
ARCHITECTURAL AND
LIGHTING ELEMENTS,
ETC., TO BE DETERMINED.
4.8%
4.8%
SDA5.1 - XX/XX/XX XXX XXX XXX XXX 1" = X'
P:\Shared\Projects\2023\2300338 Capitola Stockton Bridge Replacement\DWG\Exhibits\Cost Estimate Exhibits.dwg 06/21/2024 - 05:09 PM nankk 1:1 Sheet Plan File: Project Number: 2300338 Prepared Under the Direction of: CITY OF CAPITOLA STOCKTON AVENUE BRIDGE MITIGATION State County City California Santa Cruz Capitola
Rev Date Description Designed Drawn Checked
Scale:
Date: 04/18/2024
303 TWIN DOLPHIN DRIVE
REDWOOD CITY, CA 94065
©2024
ENGINEERING | LANDSCAPE ARCHITECTURE
SURVEYING | URBAN PLANNING
415.883.9850
WWW.CSWST2.COM
CLEAR SPAN BRIDGE
SCHEMATIC DESIGN ALTERNATIVE
PLAN
UPSTREAM ELEVATION
SCALE: 1"=10'SCALE: 1"=10'
458
Item 9 A.
Stockton Avenue Bridge – Bridge Pier Debris Mitigation Feasibility Report CSWST2 |
Appendix G – Capitola Bridge Over Soquel Creek As-Built Plans 459
Item 9 A.
California Department of Transportation
Division of Maintenance
Structure Maintenance and Investigations
BRIDGE
INSPECTION
RECORDS
INFORMATION
SYSTEM
The requested documents have been generated by BIRIS.
These documents are the property of the California Department of Transportation and should be handled in accordance with Deputy Directive 55 and the State Administrative Manual.
Records for “Confidential” bridges may only be released outside the Department of Transportation upon execution of a confidentiality agreement. 460
Item 9 A.
461
Item 9 A.
462
Item 9 A.
463
Item 9 A.
464
Item 9 A.
Stockton Avenue Bridge – Bridge Pier Debris Mitigation Feasibility Report CSWST2 |
Appendix H – Bridge Inspection Reports
465
Item 9 A.
California Department of Transportation
Division of Maintenance
Structure Maintenance and Investigations
BRIDGE
INSPECTION
RECORDS
INFORMATION
SYSTEM
The requested documents have been generated by BIRIS.
These documents are the property of the California Department of Transportation and should be handled in accordance with Deputy Directive 55 and the State Administrative Manual.
Records for “Confidential” bridges may only be released outside the Department of Transportation upon execution of a confidentiality agreement. 466
Item 9 A.
Printed on: Saturday 10/15/2022 09:36 PM Page 1 of 36C0110/AAAM/83097 Department of Transportation - Division of Maintenance Structure Maintenance & Investigations 6 Routine-Roadway View (09/25/2019) Routine-Elevation View (09/25/2019) Routine-Underside View (09/25/2019) Routine-Map View (10/05/2022)
PHOTOGRAPH IDENTIFICATION
LOCATION AT THE ESPLANADE
TEAM LEADER Shawn Hart
FACILITY CARRIED STOCKTON AVE
No.
REPORT AUTHOR Shawn Hart
FEATURE INTERSECTED SOQUEL CREEK
BRIDGE LOCATION INFORMATION
LATITUDE 36°58'20.27"
Shawn Hart (Registered Civil Engineer)
INSPECTED BY S.Hart/K.Ghazizadeh
CULVERT N N/A (NBI)
DECK 4 POOR
SUBSTRUCTURE 5 FAIR
SUPERSTRUCTURE 5 FAIR SUFFICIENCY RATING 60.6
STRUCTURALLY DEFICIENT (SD) STATUS SD
524
PAINT CONDITION N/A
STRUCTURAL HEALTH CONDITION SUMMARY INFORMATION
STRUCTURE EVALUATION 5 ABOVE MIN TOLERABLE
LONGITUDE 121°57'11.45"
SCOUR 5 STABLE W/IN FOOTING
INVENTORY RTE(ON/UNDER) ON 150000000
POSTMILE 0
ON NATIONAL HIGHWAY SYSTEM NOT ON NHS
(9)
(11)
(16)
(17)
(7)
(6)
(5)
(104)
(58)
(59)
(60)
(62)
(67) (113)
Routine Inspection
BRIDGE INSPECTION REPORT
Shawn
Hart
09/30/2023
CIVIL
68403
10/15/2022
Date
Exp.
BRIDGE NO.:
36C0110
STRUCTURE NAME:
SOQUEL CREEK May 18, 2022
INSPECTION DATE:
DECK AREA (M) 2
467
Item 9 A.
Printed on: Saturday 10/15/2022 09:36 PM Page 2 of 36C0110/AAAM/83097 Department of Transportation - Division of Maintenance Structure Maintenance & Investigations 6 3 span, continuous parabolic RC (7 cell) box girder with cantilevered end spans on RC pier walls and RC diaphragm ends with nonmonolithic wingwalls, all founded on RC pile caps and timber piles 1 @ 25 ft, 1 @ 85 ft, 1 @ 25 ft
STRUCTURE DESCRIPTION
SPAN CONFIGURATION
468
Item 9 A.
Printed on: Saturday 10/15/2022 09:36 PM Page 3 of 36C0110/AAAM/83097 Department of Transportation - Division of Maintenance Structure Maintenance & Investigations 6 UNDERWATER INVESTIGATION DETAILS - NOT APPLICABLE FOR THIS BRIDGE.
STEEL INVESTIGATION DETAILS
SCOPE AND ACCESS
This inspection was completed in accordance with SM&I standards for a routine regularly scheduled evaluation. All elements received a full visual inspection. The deck was walked and the channel was waded and probed. Flowing water was present under all spans at a depth of 2-3 feet with the pierwalls wet and the abutments dry.
NUMBERING CONVENTION
This structure alignment is east and west. The western abutment is Abutment 1 and is located nearest to the Venetian Court with the ocean on the right. The eastern abutment is Abutment 4 and is located nearest the Esplanade.
INSPECTION COMMENTARY
TYPE OF MEMBRANE
TYPE OF DECK PROTECTION
DECK STRUCTURE TYPE
TYPE OF WEARING SURFACE
WEARING SURFACE / PROTECTIVE SYSTEM
AVERAGE DAILY TRAFFIC 15000
YEAR OF ADT 2013
BYPASS, DETOUR LENGTH 3 KM
(109) TRUCK ADT % 10 %
FUTURE ADT 20403
YEAR OF FUTURE ADT 2041
HISTORICAL SIGNIFICANCE 2: ELIGIBLE FOR NRHP
0-NONE
0-NONE
0-NONE
1-CIP CONCRETE
DECK STRUCTURE INFORMATION
12.9 M
9.1 M
DECK AND ROADWAY
LANES 2
25 0-NOT ON NHS
PARALLEL STRUCTURE
TEMPORARY STRUCTURE
DEFENSE HIGHWAY
FUNCTIONAL CLASS
SPEED
NATIONAL HIGHWAY SYSTEM
TOLL
DIRECTION OF TRAFFIC
DESIGNATED NATIONAL NETWORK
TYPE OF SERVICE
FEDERAL LANDS HWY
APPR ROADWAY ALIGN 8 EQUAL DESIRABLE CRIT
DECK GEOMETRY 3 INTOLERABLE - CORRECT
APPROACH RDWY WIDTH 9.1 M
BRIDGE MEDIAN
CURB OR SIDEWALK LEFT 1.5 M RIGHT 1.5 M
TOTAL WIDTH
NET WIDTH
INVENTORY ROUTE TOTAL HORIZ CLEAR 9.1 M
INVENTORY ROUTE MIN VERT CLEAR 99.99 M
3-ON FREE ROAD
16-MINOR ARTERIAL URBAN
0-NOT STRAHNET
N-NONE EXISTS
2-2 WAY
469
Item 9 A.
Printed on: Saturday 10/15/2022 09:36 PM Page 4 of 36C0110/AAAM/83097 Department of Transportation - Division of Maintenance Structure Maintenance & Investigations 6 DESCRIPTION UNDER STRUCTURE
CHANNEL DESCRIPTION
Sandy beach outlet, tidal influence
TYPE OF SERVICE UNDER
UNDERCLEARANCES V - H N NOT APPLICABLE (NBI)
WATER ADEQUACY 7 ABOVE MINIMUM
VERT-LIFT BRIDGE NAV MIN VERTICAL CLEAR M
NAVIGATION CONTROL
NAVIGATION HORIZONTAL CLEARANCE 0.0 M
NAVIGATION VERTICAL CLEARANCE 0.0 M
PIER PROTECTION
470
Item 9 A.
Printed on: Saturday 10/15/2022 09:36 PM Page 5 of 36C0110/AAAM/83097 Department of Transportation - Division of Maintenance Structure Maintenance & Investigations 6 Photo 1
Routine Map View
OTHER PHOTOGRAPHS
210
471
Item 9 A.
Printed on: Saturday 10/15/2022 09:36 PM Page 6 of 6 36C0110/AAAM/83097 Department of Transportation - Division of Maintenance Structure Maintenance & Investigations
OTHER WORK RECOMMENDATIONS - NONE
JOINT/APPR/RAIL WORK RECOMMENDATIONS
SUPERSTRUCTURE WORK RECOMMENDATIONS - NONE
SUBSTRUCTURE WORK RECOMMENDATIONS - NONE
Work By
Work By
Action
Action
Est Cost
Est Cost
Rec Date
Rec Date
LOCAL AGENCY
LOCAL AGENCY
Joints-Repair/Clean
Railing-Repair
472
Item 9 A.
Printed on: Wednesday 03/16/2022 05:52 PM Page 1 of 36C0110/AAAL/72473 Department of Transportation - Division of Maintenance Structure Maintenance & Investigations 6 Routine-Roadway View (09/25/2019) Routine-Elevation View (09/25/2019) Routine-Underside View (09/25/2019) Routine-Map View (02/16/2022)
PHOTOGRAPH IDENTIFICATION
LOCATION AT THE ESPLANADE
TEAM LEADER Shawn Hart
FACILITY CARRIED STOCKTON AVE
No.
REPORT AUTHOR Shawn Hart
FEATURE INTERSECTED SOQUEL CREEK
BRIDGE LOCATION INFORMATION
LATITUDE 36°58'20.27"
Shawn Hart (Registered Civil Engineer)
INSPECTED BY S.Hart/J.Mok
CULVERT N N/A (NBI)
DECK 4 POOR
SUBSTRUCTURE 5 FAIR
SUPERSTRUCTURE 5 FAIR SUFFICIENCY RATING 60.6
STRUCTURALLY DEFICIENT (SD) STATUS SD
524
PAINT CONDITION N/A
STRUCTURAL HEALTH CONDITION SUMMARY INFORMATION
STRUCTURE EVALUATION 5 ABOVE MIN TOLERABLE
LONGITUDE 121°57'11.45"
SCOUR 5 STABLE W/IN FOOTING
INVENTORY RTE(ON/UNDER) ON 150000000
POSTMILE 0
ON NATIONAL HIGHWAY SYSTEM NOT ON NHS
(9)
(11)
(16)
(17)
(7)
(6)
(5)
(104)
(58)
(59)
(60)
(62)
(67) (113)
Routine Inspection
BRIDGE INSPECTION REPORT
Shawn
Hart
09/30/2023
CIVIL
68403
3/16/2022
Date
Exp.
BRIDGE NO.:
36C0110
STRUCTURE NAME:
SOQUEL CREEK September 17, 2021
INSPECTION DATE:
DECK AREA (M) 2
473
Item 9 A.
Printed on: Wednesday 03/16/2022 05:52 PM Page 2 of 36C0110/AAAL/72473 Department of Transportation - Division of Maintenance Structure Maintenance & Investigations 6 SCOPE AND ACCESS
This inspection was completed in accordance with SM&I standards for a routine regularly scheduled evaluation. All elements received a
INSPECTION COMMENTARY
3 span, continuous parabolic RC (7 cell) box girder with cantilevered end spans on RC pier walls and RC diaphragm ends with nonmonolithic wingwalls, all founded on RC pile caps and timber piles 1 @ 25 ft, 1 @ 85 ft, 1 @ 25 ft
STRUCTURE DESCRIPTION
SPAN CONFIGURATION
474
Item 9 A.
Printed on: Wednesday 03/16/2022 05:52 PM Page 3 of 36C0110/AAAL/72473 Department of Transportation - Division of Maintenance Structure Maintenance & Investigations 6 UNDERWATER INVESTIGATION DETAILS - NOT APPLICABLE FOR THIS BRIDGE.
STEEL INVESTIGATION DETAILS
full visual inspection. The deck was walked and the channel was waded and probed. Flowing water was present under all spans at a depth of 2-3 feet with the pierwalls wet and the abutments dry.
NUMBERING CONVENTION
This structure alignment is east and west. The western abutment is Abutment 1 and is located nearest to the Venetian Court with the ocean on the right. The eastern abutment is Abutment 4 and is located nearest the Esplanade.
WATERWAY
The channel cross section was re-measured during this inspection. No significant changes from the previous cross section (measured in 2013) were observed.
INSPECTION COMMENTARY
TYPE OF MEMBRANE
TYPE OF DECK PROTECTION
DECK STRUCTURE TYPE
TYPE OF WEARING SURFACE
WEARING SURFACE / PROTECTIVE SYSTEM
AVERAGE DAILY TRAFFIC 15000
YEAR OF ADT 2013
BYPASS, DETOUR LENGTH 3 KM
(109) TRUCK ADT % 10 %
FUTURE ADT 20403
YEAR OF FUTURE ADT 2041
HISTORICAL SIGNIFICANCE 2: ELIGIBLE FOR NRHP
0-NONE
0-NONE
0-NONE
1-CIP CONCRETE
DECK STRUCTURE INFORMATION
12.9 M
9.1 M
DECK AND ROADWAY
LANES 2
25 0-NOT ON NHS
PARALLEL STRUCTURE
TEMPORARY STRUCTURE
DEFENSE HIGHWAY
FUNCTIONAL CLASS
SPEED
NATIONAL HIGHWAY SYSTEM
TOLL
DIRECTION OF TRAFFIC
DESIGNATED NATIONAL NETWORK
TYPE OF SERVICE
FEDERAL LANDS HWY
APPR ROADWAY ALIGN 8 EQUAL DESIRABLE CRIT
DECK GEOMETRY 3 INTOLERABLE - CORRECT
APPROACH RDWY WIDTH 9.1 M
BRIDGE MEDIAN
CURB OR SIDEWALK LEFT 1.5 M RIGHT 1.5 M
TOTAL WIDTH
NET WIDTH
INVENTORY ROUTE TOTAL HORIZ CLEAR 9.1 M
INVENTORY ROUTE MIN VERT CLEAR 99.99 M
3-ON FREE ROAD
16-MINOR ARTERIAL URBAN
0-NOT STRAHNET
N-NONE EXISTS
2-2 WAY
475
Item 9 A.
Printed on: Wednesday 03/16/2022 05:52 PM Page 4 of 36C0110/AAAL/72473 Department of Transportation - Division of Maintenance Structure Maintenance & Investigations 6 DESCRIPTION UNDER STRUCTURE
CHANNEL DESCRIPTION
Sandy beach outlet, tidal influence
TYPE OF SERVICE UNDER
UNDERCLEARANCES V - H N NOT APPLICABLE (NBI)
WATER ADEQUACY 7 ABOVE MINIMUM
VERT-LIFT BRIDGE NAV MIN VERTICAL CLEAR M
NAVIGATION CONTROL
NAVIGATION HORIZONTAL CLEARANCE 0.0 M
NAVIGATION VERTICAL CLEARANCE 0.0 M
PIER PROTECTION
476
Item 9 A.
Printed on: Wednesday 03/16/2022 05:52 PM Page 5 of 36C0110/AAAL/72473 Department of Transportation - Division of Maintenance Structure Maintenance & Investigations 6 Side Upstream X-Section Date 09/17/2021
Measured From Top of RC Rail (left side)
6.32 7.10
7.48 7.04
6.48 6.00
3.90 Vert(m)
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Printed on: Wednesday 03/16/2022 05:52 PM Page 6 of 6 36C0110/AAAL/72473 Department of Transportation - Division of Maintenance Structure Maintenance & Investigations
OTHER WORK RECOMMENDATIONS - NONE
JOINT/APPR/RAIL WORK RECOMMENDATIONS
SUPERSTRUCTURE WORK RECOMMENDATIONS - NONE
SUBSTRUCTURE WORK RECOMMENDATIONS - NONE
Work By
Work By
Action
Action
Est Cost
Est Cost
Rec Date
Rec Date
LOCAL AGENCY
LOCAL AGENCY
Joints-Repair/Clean
Railing-Repair
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Stockton Avenue Bridge
Structural Evaluation
Findings
City Council
April 9, 2026
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Background
Stockton Bridge Evaluation
FY 22/23 City budget included $350k to evaluate debris diversion Jan 2023 – Storm impacts / debris concerns
Jan 2024 – Feasibility study initiated
Nov 2024 – Council: prioritize replacement
Mar 2025 – Council: structural evaluation requested
Apr 2026 – Evaluation complete
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Bridge is approximately 93 years old
•Evaluation confirms deterioration is widespread,
not isolated
•Repair would require major reconstruction and is
not a viable long-term solution
•Replacement is the appropriate path forward
Key Takeaways
Stockton Bridge Evaluation
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• $500,000 DWR Grant
• $350,000 General Fund FY22/23
$850,000 Total Funding
• Feasibility and Structural Evaluation
$350,000 spent to date
• Intended for design, environmental, and planning
• Not intended for major structural repair
Remaining funds
Fiscal Impact
Stockton Bridge Evaluation
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• Bridge remains in service today
• Condition will continue to decline
Status
• Preliminary Design options
• Environmental review and permitting
• Historic resource considerations
Next step: advance replacement planning
Summary and Next Steps
Stockton Bridge Evaluation
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Stockton Avenue Bridge
at Soquel Creek
(Br. No. 36C0110)
Structural Condition Evaluation
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GENERAL
DESCRIPTION
• 1933 Era Cast-in-Place Concrete Arch
• 85-foot center span with two center piers on
Timber
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HYDRAULIC
BACKGROUND • 2023 Storms Caused
Erosion at Abutments and
Corrosion Repairs were
implemented.
• CSWST2 determined
bridge to be “Scour
Critical” and developed
several hydraulic
mitigations in 2024
• Due to hydraulic
mitigation complexity, the
last alternative proposed
to replace bridge entirely.
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BRIDGE CONDITION CONSIDERATIONS
Prior to recommending overall replacement, a general condition investigation of underside of bridge deck was warranted to consider:
• Review of several existing bridge inspection reports that discussed transverse deck cracking
• Hydraulic vulnerabilities
• Age of structure
• Proximity to ocean
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EXISTING
SIDEWALK
CONDITIONS
July 2025 Site visit
(manhole access only)
• Corroding reinforcement and spalling was observed in
beneath the sidewalk. Underside of the bridge deck at
roadway manholes not visible due to formwork.
• Chain-drag evaluation of the deck located several areas that indicated delaminations of the concrete
• Additional deck openings were recommended
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EXISTING
ROADWAY DECK
CONDITIONS
March 2026 Site Visit
• Openings for bridge cell access provided for viewing of almost 20% deck slab formwork removal
• Significant spalling and corrosion consistent with
existing roadway surface cracking. The type and
frequency of this corrosion damage was not isolated.
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EXISTING
ROADWAY DECK
CONDITION
Additional Photos of Roadway Deck Soffit Spalls and
Corrosion
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EXISTING SIDEWALK DECK
CONDITION
Additional Photos of Sidewalk Slab
Soffit Spalls and Reinforcing Corrosion
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CORROSION ISSUES
• Corrosion in key structural elements, especially
bridge deck
• Concrete Spalling and Exposed reinforcement
• Ongoing maintenance needs
Still safe for use today, but condition will continue to decline over time
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Bridge Replacement
Need • Stockton Bridge is a critical link
for emergency response and
community. Nearest alternative
crossing of Creek is Highway 1.
• Bridge deck rating from recent
Caltrans Inspection Report is
currently “poor”. Caltrans
review of new data will likely
lower superstructure rating from
“fair” to “poor”.
• Bridge is considered “Scour
Critical” for hydraulics.
• Existing bridge is 93 years old,
beyond its anticipated service
life, and highly likely to be
seismically deficient.
HIGHWAY 1
CROSSING
SOQUEL AVE
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Bridge Replacement Process
• Environmental and permitting studies
• Army Corps, Regional Water Quality, US and California Fish and Wildlife, Caltrans • Multi-season construction period and maintaining 1-way signalized traffic and pedestrian access
• Caltrans review and coordination
• Historical structure issues
• Listed on Historic Bridge Inventory
• Approval through California Office of Historic Preservation • Community involvement
• Utilities in existing bridge replaced or accommodated. Bridge carries sewer, water, electrical utilities. Some of these utilities are deteriorating and do not match historical record
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Bridge Replacement Features
A replacement structure could be configured so new clear span structure would mimic existing historic character of the bridge, incorporating such features as:
• Arched bridge soffit
• Historic railing features
• Art Deco lighting and support pedestals
• Art Deco approach pedestals at abutments
• Alternative designs could be considered
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Conclusions
• Remaining service life: 5 to 10 years, but this is a rough estimate due to inaccessible areas prone to similar deterioration to what was observed. • Timing: Replacement planning should begin immediately as studies and approvals alone may take 2+ years.
• Replacement over Repair: Even a full deck replacement is not a cost-effective longterm solution as this would not address streamflow debris and seismic vulnerabilities • Risk of Delaying replacement: Continued deterioration could lead to severe cracking, unsafe conditions, partial closure with potential for prolonged roadway shutdown if failure occurs.
• Monitoring needed: A significant increase in deck cracking will warn of an impending need to close the bridge – frequent inspections (every 3 months) are recommended. 535
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Receive presentation
• Preliminary Design
• Environmental review and permitting
• Historic resource considerations
Next step: advance replacement planning
• Consider returning remaining funds
Alternative
Recommended Action
Stockton Bridge Evaluation
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Capitola City Council
Agenda Report
Meeting: April 9, 2026
From: Public Works Department
Subject: Grand Avenue Pathway – Conceptual Design and Cost Estimate Recommended Action: Receive the conceptual design and cost estimate for the Grand Avenue Pathway and provide direction on next steps.
Background: On October 23, 2025, the City Council reviewed findings completed by Pacific Crest Engineering regarding bluff erosion along Grand Avenue and discussed options for maintaining a safe pedestrian route. The report confirmed that bluff retreat is ongoing and will continue to impact the pathway over time. A relocated alignment set further inland may provide a temporary solution, estimated by Pacific Crest Engineering to be between one and ten years (Attachment 3); however, long-term stability cannot be assured.
Following that discussion, Council authorized the preparation of a conceptual design to evaluate feasibility, constraints, and cost. SSA Landscape Architects has completed a conceptual site plan and updated cost estimate for a pathway between Oakland Avenue and Central Avenue.
Discussion: The conceptual design proposes a relocated pathway shifted inland from the bluff edge to the extent feasible, generally maintaining a setback consistent with geotechnical recommendations. The pathway would be reconstructed with asphalt paving and limited concrete improvements, including curb, gutter, and drainage features. Soil/cement stabilization is included in select areas to improve subgrade conditions. Construction near the bluff would be performed by hand to minimize disturbance and reduce the risk of slope instability. Existing utilities would remain in place, and selective removal of vegetation and site features would be required to accommodate the alignment.
The geotechnical evaluation identified variability in bluff conditions along the corridor. For purposes of this project, the pathway can be generally described in two segments: Oakland Avenue to Saxon Avenue (western segment) and Saxon Avenue to Central Avenue (eastern segment). The western segment is subject to more active erosion and reduced setback from the bluff edge, while the eastern segment is comparatively more stable with greater separation from the bluff in some areas. The conceptual design applies a consistent approach along the full length of the pathway; however, the level of risk and expected service life of improvements may vary by segment.
Consistent with prior geotechnical findings, the proposed improvements represent an interim solution with a limited expected service life due to ongoing erosion.
SSA has provided a conceptual-level construction cost estimate for the proposed improvements, summarized below:
Category Estimated Cost
Temporary Facilities, SWPPP, and Field Engineering $29,600 Selective Demolition $26,525
Site Clearing $7,749
Asphalt Paving $38,040
Concrete Improvements (curb, gutter, stabilization) $60,846 Direct Construction Subtotal $162,760
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General Conditions (10%) $16,276
Contractor Overhead & Profit (15%) $24,414
Construction Contingency (10%) $16,276
Bonds & Insurance (2%) $3,255
Total Estimated Construction Cost $222,981
Selective demolition includes the removal of existing paving, vegetation, fencing, and site features, as well as an allowance for unforeseen conditions. This also reflects the removal of improvements and encroachments within the public right-of-way that have accumulated over time. Costs are influenced by restricted access, the need for hand work near the bluff, and coordination with existing site constraints.
The construction estimate does not include full project delivery costs. Based on SSA’s proposal, additional costs include preparation of construction documents, construction administration, and related expenses, which are approximately $32,000. Additional costs not yet quantified include environmental review (CEQA), Coastal permitting, and City staff time. The conceptual design has been prepared based on existing geotechnical analysis and topographic survey completed as part of Phase 1. Depending on final design and Coastal permitting requirements, supplemental geotechnical input or survey refinement may be required; however, those needs would be determined in subsequent phases.
A Coastal Development Permit (CDP) will be required for either the reconstruction of the pathway or formal closure. Coastal review will consider bluff stability, public access, and environmental impacts. The ongoing rate of erosion, as discussed at the October 2025 Council meeting, will be a key factor in permitting and feasibility.
External funding opportunities for this type of coastal bluff-top pathway project are limited. The project does not clearly align with typical state or federal grant programs, particularly given the interim nature of the improvements. Implementation would likely rely on local funding sources.
Fiscal Impact: There is no immediate fiscal impact associated with receiving this report.
Implementation of the project would require a total capital investment of approximately $250,000 to $275,000 for construction,
design, permitting, environmental review, and project delivery. The project is not well-suited to external grant funding and would likely require local funding sources.
Attachments:
1. Conceptual Site Plan
2. Preliminary Cost Estimate
3. Pacific Crest Geological Investigation (October 2025) Alignment with 2025-2029 Strategic Plan Priority: Healthy Families, Community, and Environment; Sustainable Infrastructure
Report Prepared By: Jessica Kahn, Public Works Director Reviewed By: Julia Gautho, City Clerk; Marc Tran, City Attorney Approved By: Jamie Goldstein, City Manager
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8' 6'-6" CENTRAL AVE MATCHLINE SEE NEXT SHEET
EXISTING BOLLARDS
TO REMAIN, TYP.
EXISTING DRAIN INLET
TO BE UTILIZED.
DRAINAGE BY OTHERS
EXISTING STONE
WALL TO REMAIN EXISTING CURB TO REMAIN
GRAND AVE GRAND AVE PATHWAY RENOVATION GRAND AVE,
CAPITOLA, CA 95010
SHEET
AGENCY APPROVAL
REVISIONS
NO. DATE PURPOSE
DRAWN BY
CHECKED
SCALE
DATE
JOB
303 potrero street, suite 40-c
santa cruz, ca 95060
p: 831.459.0455
f: 831-459-0484
www.ssala.com
crla no. 2805
LANDSCAPE ARCHITECTS
Exp. 1-31-28
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RNIA
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No. 2805
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JW
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03-24-2026
250022.00
NOT FOR CONSTRUCTION CITY OF CAPITOLA
1/10" = 1'-0"
SITE PLAN - WEST
L-2.0
2.1 1.3
1.4 LIMIT OF WORK
CLIFF EDGE
PROPOSED FUTURE FENCELINE
BY OTHER
PROPERTY BOUNDARY
SHEET MATCHLINE
SYMBOL ITEM
GRAPHIC LEGEND
SITE SCHEDULE
DETAIL 1.0 FLATWORK
0.0 SITE REFERENCE
DETAIL REFERENCE
SHEET REFERENCE
X/L-0.0
1.1 DETAIL 2.0 FENCING
'ASPHALT PAVING' 2.1 'PROPOSED FUTURE FENCELINE' BY OTHER 6" CONCRETE CURB 1.3
1.2 ASPHALT PAVING 1.1
BEGINNING OR END OF SITE ELEMENT
'6" CONCRETE CURB' TO BE STANDARD PC
CONCRETE PER SPECIFICATIONS & DETAIL
SYMBOL ITEM
1.3 '12" GUTTER' TO BE STANDARD PC CONCRETE
PER SPECIFICATIONS & DETAIL
12" GUTTER 1.4
2.1 TOP OF BLUFF PER GEOTECH REPORT
1.4 15' SETBACK FROM TOP OF BLUFF
SOIL/CEMENT STABILIZATION 1.2
1.5 EXISTING UTILITIES TO REMAIN IN PLACE
'SOIL/CEMENT STABILIZATION' PORTLAND CEMENT
ROTOTILLED 6" INTO EXISTING SOIL, ROLLED LEVEL. ALL
WORK TO BE DONE BY HAND, SEE SITE IMPROVEMENT NOTE 1
1.1 BEGIN
1.5 1.5 CURB TO CREATE BULB
OUT AROUND EX. UTILITIES
1. ANY WORK PERFORMED ON THE FOOTPATH BETWEEN OAKLAND AVENUE AND SAXON AVENUE SHOULD BE DONE BY HAND WITHIN 15 FEET OF THE TOP OF THE BLUFF PER GEOTECH REPORT. THE USE OF HEAVY VIBRATORY EQUIPMENT SHOULD BE AVOIDED IF POSSIBLE, TO LESSEN THE POSSIBILITY OF TRIGGERING FURTHER LANDSLIDING OF THE BLUFF. IF HEAVY EQUIPMENT IS USED, THE WORK SHOULD ONLY BE PERFORMED WHEN THE MARINE TERRACE DEPOSITS ARE DRY, TYPICALLY LATE SPRING (MAY) THROUGH FALL (OCTOBER).
2. ACCESS ROUTES AND STAGING AREAS ARE TO BE STRICTLY ADHERED TO. STAGING AREAS TO BE DETERMINED BY OWNER'S REPRESENTATIVE.
3. UPON COMPLETION OF ACCESS AND STAGING, THE SITE SHALL BE REPAIRED TO "AS WAS" OR BETTER THAN EXISTING CONDITIONS.
4. CONSTRUCTION SIGNAGE SHALL BE PROVIDED BY THE CONTRACTOR AND BE POSTED AT EACH JOB SITE IN CLEAR VIEW. POST A "KEEP OUT-CONSTRUCTION AREA" SIGN.
5. ALL DIMENSIONS SHALL BE VERIFIED IN THE FIELD AND CHALKED, STRING LINED, OR FLAGGED PRIOR TO ANY CONSTRUCTION. IMMEDIATELY NOTIFY OWNERS REPRESENTATIVE OF ANY DISCREPANCIES OR VARIATIONS FROM THE PLANS AS DRAWN AND RE-DIRECT WORK TO AVOID DELAY.
6. ALL DIMENSION LINES ARE EITHER PERPENDICULAR TO OR PARALLEL TO THE ELEMENT FROM WHICH IT IS DIMENSIONED UNLESS OTHERWISE INDICATED ON THE PLANS.
7. THE INTERFACE OF ALL PROPOSED IMPROVEMENTS TO EXISTING SITE SHALL CONFORM TO EXISTING CONDITIONS IN A SMOOTH AND UNIFORM MANNER.
8. ALL REINFORCING AND FORMS SHALL BE SECURED IN PLACE AND INSPECTED BY OWNERS REPRESENTATIVE PRIOR TO PLACING ANY CONCRETE.
9. THE CONTRACTOR SHALL ENSURE THE SITE IS SECURE AT ALL TIMES AND LOCKED DURING NON-CONSTRUCITON ACTIVITIES.
SITE IMPROVEMENT NOTES
1. CONCRETE FINISHES SHALL BE PER SPECIFICATIONS UNLESS OTHERWISE NOTED ON THE PLANS.
MATERIALS AND FINISHES NOTES
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8' 5' 15' OAKLAND AVE SAXON AVEMATCHLINE SEE NEXT SHEET
EXISTING DRAIN INLET
TO BE UTILIZED.
DRAINAGE BY OTHERS GRAND AVE PATHWAY RENOVATION GRAND AVE, CAPITOLA, CA 95010
SHEET
AGENCY APPROVAL
REVISIONS
NO. DATE PURPOSE
DRAWN BY
CHECKED
SCALE
DATE
JOB
303 potrero street, suite 40-c
santa cruz, ca 95060
p: 831.459.0455
f: 831-459-0484
www.ssala.com
crla no. 2805
LANDSCAPE ARCHITECTS
Exp. 1-31-28
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RNIA
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OF CAL
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No. 2805
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JW
JB
03-24-2026
250022.00
NOT FOR CONSTRUCTION CITY OF CAPITOLA
1/10" = 1'-0"
SITE PLAN - EAST
L-2.1
LIMIT OF WORK
CLIFF EDGE
PROPOSED FUTURE FENCELINE
BY OTHER
PROPERTY BOUNDARY
SHEET MATCHLINE
SYMBOL ITEM
GRAPHIC LEGEND
SITE SCHEDULE
DETAIL 1.0 FLATWORK
0.0 SITE REFERENCE
DETAIL REFERENCE
SHEET REFERENCE
X/L-0.0
1.1 DETAIL 2.0 FENCING
'ASPHALT PAVING' 2.1 'PROPOSED FUTURE FENCELINE' BY OTHER 6" CONCRETE CURB 1.3
1.2 ASPHALT PAVING 1.1
BEGINNING OR END OF SITE ELEMENT
'6" CONCRETE CURB' TO BE STANDARD PC
CONCRETE PER SPECIFICATIONS & DETAIL
SYMBOL ITEM
1.3 '12" GUTTER' TO BE STANDARD PC CONCRETE
PER SPECIFICATIONS & DETAIL
12" GUTTER 1.4
2.1 TOP OF BLUFF PER GEOTECH REPORT
1.4 15' SETBACK FROM TOP OF BLUFF
SOIL/CEMENT STABILIZATION 1.2
1.5 EXISTING UTILITIES TO REMAIN IN PLACE
'SOIL/CEMENT STABILIZATION' PORTLAND CEMENT
ROTOTILLED 6" INTO EXISTING SOIL, ROLLED LEVEL. ALL
WORK TO BE DONE BY HAND, SEE SITE IMPROVEMENT NOTE 1
1.3 1. ANY WORK PERFORMED ON THE FOOTPATH BETWEEN OAKLAND AVENUE AND SAXON AVENUE SHOULD BE DONE BY HAND WITHIN 15 FEET OF THE TOP OF THE BLUFF PER GEOTECH REPORT. THE USE OF HEAVY VIBRATORY EQUIPMENT SHOULD BE AVOIDED IF POSSIBLE, TO LESSEN THE POSSIBILITY OF TRIGGERING FURTHER LANDSLIDING OF THE BLUFF. IF HEAVY EQUIPMENT IS USED, THE WORK SHOULD ONLY BE PERFORMED WHEN THE MARINE TERRACE DEPOSITS ARE DRY, TYPICALLY LATE SPRING (MAY) THROUGH FALL (OCTOBER).
2. ACCESS ROUTES AND STAGING AREAS ARE TO BE STRICTLY ADHERED TO. STAGING AREAS TO BE DETERMINED BY OWNER'S REPRESENTATIVE.
3. UPON COMPLETION OF ACCESS AND STAGING, THE SITE SHALL BE REPAIRED TO "AS WAS" OR BETTER THAN EXISTING CONDITIONS.
4. CONSTRUCTION SIGNAGE SHALL BE PROVIDED BY THE CONTRACTOR AND BE POSTED AT EACH JOB SITE IN CLEAR VIEW. POST A "KEEP OUT-CONSTRUCTION AREA" SIGN.
5. ALL DIMENSIONS SHALL BE VERIFIED IN THE FIELD AND CHALKED, STRING LINED, OR FLAGGED PRIOR TO ANY CONSTRUCTION. IMMEDIATELY NOTIFY OWNERS REPRESENTATIVE OF ANY DISCREPANCIES OR VARIATIONS FROM THE PLANS AS DRAWN AND RE-DIRECT WORK TO AVOID DELAY.
6. ALL DIMENSION LINES ARE EITHER PERPENDICULAR TO OR PARALLEL TO THE ELEMENT FROM WHICH IT IS DIMENSIONED UNLESS OTHERWISE INDICATED ON THE PLANS.
7. THE INTERFACE OF ALL PROPOSED IMPROVEMENTS TO EXISTING SITE SHALL CONFORM TO EXISTING CONDITIONS IN A SMOOTH AND UNIFORM MANNER.
8. ALL REINFORCING AND FORMS SHALL BE SECURED IN PLACE AND INSPECTED BY OWNERS REPRESENTATIVE PRIOR TO PLACING ANY CONCRETE.
9. THE CONTRACTOR SHALL ENSURE THE SITE IS SECURE AT ALL TIMES AND LOCKED DURING NON-CONSTRUCITON ACTIVITIES.
SITE IMPROVEMENT NOTES
1. CONCRETE FINISHES SHALL BE PER SPECIFICATIONS UNLESS OTHERWISE NOTED ON THE PLANS.
MATERIALS AND FINISHES NOTES
1.4 1.5 1.2 END 2.1
1.5 1.5
1.1 541
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TOTAL COST
$162,760
General Conditions $16,276
General Contractor Profit & Overhead $24,414
Construction Contingency $16,276
Bonds and Insurance $3,255
SPEC # ITEM DESCRIPTION QTY UNIT UNIT PRICE ITEM COST
01 50 00 TEMPORARY FACILITIES AND CONTROLS $3,000
Construction Fencing 1 ls $3,000.00 $3,000
01 57 00 TEMPORARY STORM WATER POLLUTION CONTROL $18,600 Temporary Drainage Inlet Protection 2 ea $300 $600
Temporary Erosion Control 1 allow $18,000 $18,000
01 73 00 FIELD ENGINEERING $8,000
Layout and staking 1 allow $8,000.00 $8,000
02 41 19 SELECTIVE DEMOLITION $26,525
Demolish & remove existing asphalt paving 1195 sf $4.00 $4,780 Demolish & remove existing pavers 156 sf $5.00 $780
Demolish & remove existing site wall BY HAND 1 allow $1,500.00 $1,500 Demolish & remove existing wood edging 81 lf $5.00 $405 Remove Existing Tree 3 ea $1,200.00 $3,600
Remove Existing Shrub 33 ea $150.00 $4,950
Remove & Relocate existing site furnishings 1 allow $3,500.00 $3,500 Demolish & remove existing fence BY HAND 44 lf $20.00 $880 Demolish & remove existing fence 226 lf $5.00 $1,130
Unforseen conditions 1 allow $5,000.00 $5,000
31 10 00 SITE CLEARING $7,749
Clear and grub BY HAND 1158 sf $5.00 $5,790
Clear and grub 3265 sf $0.60 $1,959
32 12 16 ASPHALT PAVING $38,040
Asphalt paving 3804 sf $10.00 $38,040
32 13 13 CONCRETE PAVING $60,846
Soil/Cement Stabilization BY HAND 480 sf $15.00 $7,200
6" Curb & Gutter 472 lf $93.00 $43,896
1' Cross Gutter 150 lf $65.00 $9,750
$222,981
Grand Ave Pathway
Project No. 250022.00
Preliminary Conceptual Plan
March 30, 2026
10%
15%
10%
SUBTOTAL
2%
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GEOTECHNICAL | ENVIRONMENTAL | CHEMICAL | MATERIAL TESTING | SPECIAL INSPECTIONS 444 AIRPORT BLVD., SUITE 106 | WATSONVILLE, CA 95076 | PHONE 831-722-9446 | WWW.4PACIFIC-CREST.COM 14 October 2025 Project No. 2381.2
City of Capitola, Public Works
Attention: Jessica Kahn, Public Works Director
420 Capitola Ave
Capitola, California 95010
Phone: (831) 475-7300
[email protected]
Re: Updated limited geological investigation of coastal bluff failure Grand Avenue footpath between Oakland and Central Avenues Capitola, California 95010
REFERENCES
“Re: Limited geological investigation of coastal bluff failure - Grand Avenue footpath near intersection with Oakland Avenue and Saxon Avenue - Capitola, California 95010”, unpublished consultant letter by Pacific Crest Engineering, dated 9 June 2023 “Re: Limited geological investigation of coastal bluff failure - Grand Avenue near intersection with Oakland Avenue and Hollister Avenue - Capitola, California 95010”, unpublished consultant letter by Zinn Geology, dated 15 May 2017
Dear Jessica:
This letter presents the results of our updated limited geological investigation of the ongoing bluff failures that have undermined portions of the footpath along Grand Avenue between its intersection with Oakland Avenue and Central Avenues (see Plate 1). Our work and this letter build upon the work completed previously in this area by Zinn Geology (2017) and Pacific Crest Engineering (2023). The reader should refer to those letters for a detailed discussion about the ongoing geological processes driving the configuration of the coastal bluff and its retreat.
Over the long term, the bluff below the footpath has been episodically retreating as the soil and bedrock exposed on the bluff face erodes and fails in the form of shallow landslides, debris flows and rock falls, mostly in response to intense storms, wave erosion and earthquakes. The most recent shallow landslides that have caused the top of the bluff to retreat and undermine the footpath this winter appear to have been driven by a combination of a large slab toppling failures of the Purisima Formation bedrock face of the bluff, saturation of the marine terrace deposits soil that caps the underlying Purisima Formation bedrock, as well as erosion of the Marine Terrace Deposits where a culvert flows out of the face of the bluff.
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City of Capitola –Bluff Retreat Along Grand Avenue footpath between Central and Oakland Aves. Project No. 2381.2 14 October 2025
The overall long term failure process for the coastal bluff at this location is a two-part process. The Purisima Formation bedrock exposed in the lower bluff is eroded and notched at the base by waves until the notch intersects a nearly vertical bluff-parallel joint set, at which point a slab of bedrock slides downward or topples, typically from top to bottom for the exposed slab. The bedrock topple process also takes the overlying cap of marine terrace deposits along with it leaving a very steeply dipping to nearly vertical scar in the bluff face that freshly exposes both the bedrock and marine terrace deposits. At that point, the wave scour process begins anew at the base of the bluff, eventually carving another notch into the bedrock. The marine terrace deposits concurrently begin to erode and slide in a piecemeal fashion as they seek the angle of repose of about 38 degrees for the sand and gravels that compose that majority of the formation. This process continues unabated until the bedrock topples again in the future, resetting the entire retreat process geometry and clock.
For this current work we have mapped the position of the top of the bluff using a combined data set of our own drone flight and a surveyed base map prepared and provided by Bowman and Williams. The base map also shows the location of the current fence line and property lines.
The bluff is in various states of failure between Central and Oakland Avenues. Portions of the bluff have recently failed from top to bottom in response to intense storms of the past winters coinciding with El Nino Climatic events. In some locations, the bedrock exposed in the bluff is dilated and appears to be primed for toppling. Deep notches within the bedrock at the base of the bluff and sea caves have been observed during our field reconnaissance in this area in past years.
We also reviewed a geological report for the Depot Hill Geological Hazard Abatement District, prepared on 12 April 2000 by Rogers Johnson and Associates. The report documents a past calculated long term bluff retreat rate of about 1.0 feet per year at that time. The authors also cautioned the reader that the bluff had been severely undercut at that point, implying that a large failure of the bluff was imminent. This process described by them isn’t a one time event – as noted above this is an ongoing cyclical process that is constantly driving the face of the bluff landward.
As noted at the beginning of this letter, the fate of the bluff and the retreat is always tied to what is happening at the base of the bluff with respect to notching and formation of sea caves. We noted two distinct conditions with respect to that observation for the area studied:
1. Various portions of the bluff failures between Central and Oakland Avenues that have occurred in the last several winters appear to have been triggered by toppling of undercut bedrock.
2. Some of landslides that have occurred in the last several winters between Central and Oakland Avenues appear to have been within the marine terrace deposits only. 544
Item 9 B.
City of Capitola –Bluff Retreat Along Grand Avenue footpath between Central and Oakland Aves. Project No. 2381.2 14 October 2025