01A. Powerpoint
Stevens Creek
Corridor Park
Design Update
~ Final CreekAlignment
and
~ Project Phasing
City Council
Study Session
January 17, 2006
•Early in the visioning process the City Council
directed that creek restoration drive the park
improvement project
•The environmental document we will release in
February includes a description of a park where
habitat restoration, community use and revenue
generation coexist with a multiuse trail
•The most significant aspect of the restoration
effort is the removal of barriers to fish passage and
the realignment of Stevens Creek
•The Santa Clara Valley Water District staff and
our consulting biologists, hydrologists, and
geomorphologists have been working for eight
months to identify the alignment that best achieves
the project objectives
•The process included a physical survey of the
creek, analysis of flow data, review of historical
information, and preparation and review of a
number of biological reports
•The landscape architect tasked with designing the
park then met with Blackberry Farm staff to work
out the details of the park plan. Factors considered
by the landscape architect included:
–Blackberry Farm Picnic Grounds operations: creating a
community park around an existing business
–Locating permanent structures out of the flood plain
–Retaining as many trees as possible, and
–Addressing resident concerns
City Council actions to date that have been
incorporated into the current plan:
•Reduce the capacity of the picnic area to 800
persons from the current 4,000 person capacity –
reduce the parkland given over to parking
•Extend the trail from Stevens Creek Blvd. through
McClellan Ranch to McClellan Road
•Close access from Scenic Circle
•The most significant change to the park plan
involves the creek realignment
•We have worked in partnership with the Water
District so that flood control and habitat goals are
addressed
•The stream shifts in two areas to reclaim a more
natural alignment horizontally and achieve a
desirable gradient after the vertical barriers to fish
passage are removed
Hardened channel banks
2009
Diversion dam and low flow
road crossings
2007
Concrete rubble
2009 or 2010
Channel Realignment –Reaches A & B
Proposed creek
East-aligned
alignment will
trail
allow removal of
barriers to fish
passage
Restored area
Which is
Restoration
currently
planting
parking area
Current creek
alignment
Creating Fish and Riparian Habitat
Pool and Riffle Creek Diagram
Permeable
Sediments
Oxbow River & Stream Restoration, Inc.
Diversion Dam and 1Low
st
Flow Crossing to be removed
Before
Restoration of Powderlick Run
September 2003
3 months post
Oxbow River & Stream Restoration, Inc.
In-stream Design Elements
•Representative cross sections
–Riffle
–Pool/bend
•Large woody debris structures
–Digger logs
–Spider logs
Typical RiffleCross Section –Reaches A & B
Typical Pool/BendCross Section –
Reaches A & B
Large Woody Debris Structures
Spider Log
Spider Log
Digger Log
Digger Log
(Source: California Salmonid Stream Habitat Restoration Manual)
(Source: California Salmonid Stream Habitat Restoration Manual)
Proposed Channel Re-alignment for Reach A
Proposed Channel Re-alignment for Reach B
Soil
Bio-engineering
•Reinforces the soil mantel
•Provides high root density
•Fast growing
•Least cost to plant
•Overhanging vegetation
•Shade, leaf detritus
Oxbow River & Stream Restoration, Inc.
18 months post
3 years post
Phasing
•The Stevens Creek Corridor Park project will
likely be constructed in three phases, with the first
phase to be constructed in 2007
•The first phase will include:
–Park upgrades
–Trail
–Creek restoration and barrier removal
–Improvements to the 4-H area
–Phase one environmental classroom
Park/picnic upgrades
Relocation of the
maintenance
facilities
Trailhead rest rooms to be
renovated (total 200 sq. ft.), 2
benches and directional signs
in this area
Trailhead parking
Native plantings to be installed
in area disturbed by trail
construction
200 LF split rail fencing
to keep cyclists off the
nature trail
Environmental classroom
to replace caretaker’s
trailer
•Phase Two will likely include:
–More creek restoration in the Horseshoe Bend
area with additional plantings
–We are awaiting word on a grant application
submitted six months ago. If funded we will
construct in 2007.
•Later phases
–Extend park and trail through Stocklmeir
property:
•Meeting with Cupertino Historical Society to view
the status of their plans for the site
•They will be invited to P&R Comm. February
meeting if they are ready to go public with their
plans
–Remove concrete at McClellan Ranch
Reach C –Stocklmeir
Orchard
Reach B –
Chestnut Picnic
Area
Reach A –
Horseshoe Bend
Diversion Dam and 1 st
Low Flow Crossing
:Blackberry Farm Golf
Reach C
Course and Stocklmeir Orchard
Reach C Existing Conditions
Looking upstream
Looking downstream
Proposed Channel Re-alignment for Reach C
800Channel Invert (feet)
Reach C Riffle-Pool Layout
291
Four step-pools at
beginning of reach
Reach C Riffle-Pool Layout
290
289
288
287
286
Very long and deep
"refuge" pool
285
284
283
282
281
280
0100200300400500600700
Longitudinal Stationing from start of Reach C (feet)
Weirs & Vanes
•Deflect flows
away from
eroding banks or
infrastructure
•Can be
constructed to
allow fish
passage
•Are “stepped”to
accommodate the
changes in
stream gradient
Little Beaver Creek
•Weir structures are
concreted into place and
usually require management
over time
•Weir structures do not
provide the spawning gravel
for quality of habitat that the
Rosgen structures, Pagosa Springs, Colorado
Phase One Elements
(2007 construction)
•Parking reduced in proportion to resized
picnic facility to 372:
–350 -picnic area
–5 -Retreat Center
–17 -trailhead
•Creek realignment:
–More natural alignment
–Maintains the greatest number of trees
–Greater space for west bank picnicking and
vegetation buffer
•Entry kiosk for fee collection:
–sited so that traffic can flow into the park
–fee-for-use access is separated from the trail access
•Pool/snack area reconfigured so that staff can
monitor fee-paying picnickers separately from the
park users, while keeping the trail and snack bar
open to the community
•Trail
•Environmental classroom
Funding
Funding is at hand to:
•Relocate the maintenance facility
(Per Capita and Roberti-Z’Berg-Harris)
•Redo the picnic area
(Urban Park Act)
•Remove the barriers to fish passage
(Depart. Water Res. & SCVWD)
•Construct the first phase of the environmental classroom
(Roberti-Z’Berg-Harris)
•Enhance native plantings
(Depart. Water Res. & Clean Safe Creeks)
•Reconfigure 4-H Club area and community garden
(Clean Safe Creek)
•Construct the trail from McClellan Ranch to Blackberry
Farm
(Clean Safe Creek)
None of these project elements are funded at the “Cadillac”
level, but we have great faith in the project team to deliver a
quality project for the money we have available.
Process From This Point
•The City Council will review this information in a
study session on January 17 from 5:30 –6:30 p.m.
No action will be taken:
–The FAHCE Committee will receive a briefing
on January 24
–The environmental document will be released
to the public in February –all of our “interested
parties”will be notified
•All regulatory agencies will have an opportunity
to have input, and input will be utilized in the
drafting of environmental mitigations
•These agencies are the agencies that issue permits
to enable project construction
•Once environmental review has been completed
and the permits are in hand, we will have
authorization to call for bids for construction
•While the enviromental review is underway,
staff will:
–Solicit proposals for cosultant team for
construction documents
–Prepare architectural plans for the
environmental classroom for design review and
permitting
–Continue to pursue grant funds