Stakeholder Meeting #1
June 14, 2001
March 11, 1995
Opening Remarks and Agenda Overview

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June 14, 2001
Congressman Sam Farr’s Office —
Alec Arago
County of Monterey —
Bill Phillips, Deputy County
Administrator
County of Santa Cruz —
Susan Mauriello, County
Administrator
Agenda Overview —
Tim Gilbert, MIG, Inc.
Opening Remarks and Agenda Overview
Today’s Meeting Purpose
To provide stakeholders with an overview of the
project and and planning process. Get input
regarding project issues and opportunities.
Today’s Agenda
I.
II.
III.
IV.
V.
VI.
June 14, 2001
Welcome
Project Background & Planning Process
Structure
Discussion of Visions, Goals, and Expectations
Project Challenges and Opportunities
Discussion of Issues, Opportunities and
Constraints
Summary and Next Steps
Project Background
The Problem— Insufficient Flood Protection
June 14, 2001
Project Background
The Problem - Long History of Floods and
Planning Efforts
June 14, 2001
Project Background
The Problem - Long History of Floods and Planning Efforts
1936
Federal Flood Control Act authorizes flood control .
1949
Levee System Construction is completed along Pajaro River
and Salsipuedes Creek
1955
First major flood event to breach levees
1966
Federal Flood Control Act authorizes new project
1974-5
Local community declines to support any identified project alternative
1982/6
Flooding occurs along Salsipuedes/Corralitos Creeks
1995
Major flood event breaches Pajaro River levees; flows exceed design capacity
1997
Flooding occurs along Corralitos Creek
1999
Pajaro River mainstem is combined with Salsipuedes/ Corralitos Creek project
2000
Corps of Engineers agree to Community Planning Process
June 14, 2001
Project Goal
Desired outcome of the Community
Planning Process:

June 14, 2001
Achieve agreement on a
community-based concept plan
for Pajaro River flood protection.
Project Goal
The Phase I Challenge…
Develop a Community Concept Plan for
Detailed Study
No Build
June 14, 2001
Community
Concept Plan
1974 & 1996
Corps Plans
Planning Process and Structure
Phase I
Concept Plan — November 2001
Phase II
2002
Final Design & Environmental Certification —
Phase III
2003
Federal Funding & Authorization —
Phase IV
Initiate Construction — 2004
Phase V
Project Completion — 2008
June 14, 2001
Planning Process and Structure
Project Sponsors:


Monterey and Santa Cruz Counties
U.S. Army Corps of Engineers
Stakeholders:

June 14, 2001
31 Pajaro Valley organizations, constituency
representatives, and regulatory agency stakeholders
to work together to achieve a consensus Concept
Plan, convened by Congressman Sam Farr
Planning Process and Structure
Stakeholders:

City of Watsonville

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Dave Tavarez-Town of Pajaro
Joseph Rosa-Town of Pajaro
Vince Carrillo-Town of Pajaro
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John Martinelli-Santa Cruz
Richard Uyematsu-Santa Cruz
Karen Miller-Monterey
Patricia Sakata-Monterey
Jim Rider-Farm Bureau
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June 14, 2001
CA Coastal Commission-Tami Grove
CA Fish & Game-Patricia Anderson
CA Coastal Conservancy-Patsy Heasly
US Fish & Wildlife-Amelia Orton-Palmer
National Marine Fisheries –Joyce Ambrosius
Monterey Bay Marine Sanctuary- Holly Price
Wetlands Watch-Chris Johnson-Lyons
Sierra Club-JoAnn Baumgartner
Elkhorn Slough -Mark Silberstein
Melanie Mayer Gideon
Residents in Floodplain

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Bill Mancovich-Santa Cruz
Ed Kelly-Santa Cruz
Diane Young-Monterey
Karen Sambraillo-Pajaro
Local Environmental Organizations

Regulatory Agencies

Business Representatives

Farm Representatives in Floodplain

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Carlos Palacios-City Manager
Town of Pajaro

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Vergie Neighbors-Santa Cruz
Dan Hernandez-Santa Cruz
Diane Cooley-Monterey
John Kasunich-Monterey
Community Organizations
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Casa de la Cultura-Sister Rosa Delores
Action Pajaro Valley-Lisa Dobbins
Com. Alliance Family Farmers-Sam Earnshaw
Planning Process and Structure
How we are organized to accomplish Phase I
…
2001
MAY
JUNE
Project Primer
Stakeholder
Issues
Stakeholder
Meeting #1
JULY
AUGUST
SEPTEMBER
OCTOBER
Design Options
Design Options
Urban Areas
Rural Areas
Draft
Concept
Stakeholder
Meeting #3
Stakeholder
Meeting #4
Stakeholder
Meeting #2
NOVEMBER
Final
Concept
Stakeholder
Meeting #5
Community Focus Groups, Stakeholder Interviews, Bi-lingual Outreach
Working
Group
June 14, 2001
Working
Group
Working
Group
Working
Group
Working
Group
Working
Group
Working
Group
Planning Process and Structure
The Stakeholder Process is supported by a
Working Group:
Working Group Role…
• Listen to Stakeholders
• Provide technical answers to Stakeholders
• Hydraulics
• Environmental
• Finance
• Initiate project design options for Stakeholder
discussion and debate.
June 14, 2001
Planning Process and Structure
Working Group…Resource to Stakeholders

City of Watsonville

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Army Corps of Engineers

David Koch—Public Works Director
Steve Palmisano—Environmental Proj. Manager
Santa Cruz County

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Susan Mauriello—County Administrator
Tom Bolich — Public Works Director
Peter Cota-Robles — Zone 7 Project Manager
Ken Hart-Environmental Coordinator
Consultants

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Arijis Rakstins — Project Management
Erich Bluhm —Project Manager
Jim Howells — Project Manager
Dave Dickson—MIG, Inc.
Tim Gilbert—MIG, Inc.
Ed Wallace — NW Hydraulics Inc.
Ken Myers — HDR Engineering Inc.
Rick Swift-CH2M Hill Engineering Inc.
Monterey County


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Bill Phillips — Deputy CAO
Curtis Weeks — MCWRA General Manager
Joe Madruga — Zone 1 Project Manager
Scott Hennessey—Planning Director

Project Oversight


Observer

June 14, 2001
Alec Arago—U.S. Congress Member
Sam Farr
Patsy Heasly, CA Coastal Conservancy
Planning Process and Structure
The role of consultant team in the
process…
• Facilitate consensus-based process
• MIG, Inc.
• Conduct outreach to diverse constituency groups;
• 6 Focus Group Meetings-coordinated through the
Stakeholders- MIG, Inc.
• Provide the necessary technical data and research:
• Northwest Hydraulic Consultants (NHC) Inc.
• CH2MHill Engineering Inc.
June 14, 2001
Planning Process and Structure
Concurrent Army Corps of Engineers Milestones…
2001
JUNE
JULY
Begin
EIS/EIR
Scoping
AUGUST
SEPTEMBER
OCTOBER
Develop and Examine
Environmental Baseline
Conditions
June 21
NOVEMBER
Select Alternatives
for Detailed EIR/EIS
Final
Community
Concept
Stakeholder
Meeting #1
June 14, 2001
Stakeholder
Meeting #2
Stakeholder
Meeting #3
Stakeholder
Meeting #4
Stakeholder
Meeting #5
Planning Process and Structure
The role of general government elected
officials in the process…
•
Congress Member Sam Farr, 17th District
•
Senator Bruce McPherson, 15th District
•
Assembly Member, Speaker Pro Tem Fred Keeley, 27th District
•
Assembly Member Simon Salinas, 28th District
•
Supervisor Tony Campos - Santa Cruz County, 4th District
•
Supervisor Ellen Pirie - Santa Cruz County, 2nd District
•
Supervisor Lou Calcagno - Monterey County, 3rd District
•
Mayor Chuck Carter - City of Watsonville, 3rd District
•
Council Member Betty Bobeda - City of Watsonville, 7th District
June 14, 2001
Project Approvals-Who Decides?
Environmental
Impact Report
(NEPA)
Environmental
Impact
Statement
401 Water
Quality Permit
Project
Cooperation
Local Finance
Plan

Corps of
EngineersDC
APPROVAL


Monterey &
Santa Cruz
Boards of
Supervisors
APPROVAL

Central Coast
Regional
Water Quality
Control Board
APPROVAL


City of
Watsonville


REG
AUTHORITY

USFWS

NMFS

EPA
REG
AUTHORITY


June 14, 2001
CA Coastal
Commission
CA Fish &
Game
REG
AUTHORITY

State Water
Quality
Control
Board

Santa Cruz &
Monterey
Zone Boards
County
Boards of
Supervisors
Landowners
Voters: (2/3
for special
tax)
Corps of
Engineers
Construction
Start &
Appropriation
Agreement
(CEQA)
APPROVAL
Congressional
APPROVAL


Monterey &
Santa Cruz
Boards of
Supervisors
Corps of
Engineers
APPROVAL


Local
Congressional
Congress
Planning Process and Structure
23 flood protection alternatives studied since 1966
June 14, 2001
Planning Process and Structure
23 flood protection alternatives studied since 1966
June 14, 2001
Consensus Process
23 flood protection alternatives studied since 1966
• No project
• Set-back
levees
and increase in
levee
height
Community
Concept Plan
• Retention to
upper basin
reservoirs
June 14, 2001
• Bypass
Channels
• Rebuild/increa
se
height of
levees in
place
• Floodwalls
built on top of
existing
levees
Planning Process and Structure
Framework for evaluation of plan alternatives:
HYROLOGY &
HYDRAULICS



Level of
Protection
Water Surface
Elevations
Geomorphic
Stability
ENVIRONMENTAL
SOCIO-ECONOMIC
FINANCIAL
& REGULATORY
CONSIDERATIONS
FEASIBILITY

Endangered
and Threatened
Species



Project
Approvals



Water
Quality
Regulations
Future
Environmental
Regulations


Agricultural
Land Impacts
Business
Impacts
Residential
Impacts



Economic
Development
Federal/Local
Cost Sharing
Local Share of Cost

State Funding

Visual Impacts
Recreation
Federal
Authorization



June 14, 2001
Flood
Protection
Who pays for local
share of cost?
Financing Options
Consensus Process
Key Elements to Success
• Emerging Mission - Crisis/ Mandate
• Common knowledge
Shared meaning
• Relationships among traditional adversaries
Creative problem solving
• Community of place
• No better deals elsewhere
• Primary parties participate in good faith
• Multiple issues for trade off
Community Benefits
• Constituencies open to a deal
• Adequate resources
June 14, 2001
Multiple
Ground Rules
• All Stakeholder meetings will be open to the
public.
• All meetings will have agendas with meeting
objectives clearly identified.
• Meetings will be documented in summary
reports.
• Stakeholder Group members are expected to
attend all meetings. Stakeholders will notify the
Stakeholder Support Staff if they expect to be
absent: Justine - 454-3484
• Stakeholder Group members will utilize active
listening skills and refrain from interrupting
June 14, 2001
Ground Rules
• Issues or concerns about process must be brought to
the Stakeholder Group as a whole for discussion.
• Stakeholder Group members will share relevant
information and facts to facilitate progress.
• An attempt will be made to reach all decisions and
recommendations by consensus.
• Stakeholder Group members and the Working Group
will complete all assignments in a timely fashion.
• Stakeholder Group members will show courtesy and
respect for each other when giving or receiving
positive or negative feedback and contrary opinions.
June 14, 2001
Consensus Process
Three possible planning processes…
OUTCOME
Possible
Outcome
I
Complete Consensus
All members of the Stakeholder group are in
agreement with everything.
RESULT
Flood
Project
Likely
Classic Consensus
Possible
Outcome
II
A. I agree with most of the recommendations
and I am willing to support all of them.
B. I agree with many of the recommendations
and I will not oppose them.
C. I do not agree with the recommendations
but I will not actively oppose them.
Minority & Minority Reports
Possible
Outcome
III
June 14, 2001
A. Number of members who agree.
B. Number of members who do not agree.
C. Number of members who abstain.
Flood
Project is
Possible
High Risk of
No Action
Project Goal
Desired outcome of the Community
Planning Process:

June 14, 2001
Achieve agreement on a
community-based concept plan
for Pajaro River flood protection.
Open Discussion: Vision, Issues,
Expectations
Flood Project Challenges and Opportunities

Hydrology and Hydraulics Primer—
General Project Alternatives—
Ed Wallace/ Loren Murray , NHC Inc.

Environmental and Regulatory
Considerations—
Ken Hart, Santa Cruz County Planning Dept.

Socio-Economic Considerations—
David Koch, City of Watsonville Public Works Dept.

Financial Feasibility—
David Dickson, MIG Inc.
June 14, 2001
Flood Project Challenges and Opportunities
Hydrology and
Hydraulics Primer—
Ed Wallace / Loren Murray
Northwest Hydraulic Consultants (NHC) Inc.
June 14, 2001
Hydrology and Hydraulics
Framework for evaluating plan alternatives:
June 14, 2001

Level of Protection

Water Surface Elevations

Geomorphic Stability
Hydrology and Hydraulics
Level of Flood Protection:
Current Protection:

Pajaro River: 25 year storm protection (32,000 cfs)

Salsipuedes Creek: 7 year storm protection (5,000 cfs)
100 Year Storm Flows:
June 14, 2001

Pajaro River: 49,000 Cubic Feet Per Second (cfs)

Salsipuedes Creek (@ Pajaro River): 8,500 cfs

Corralitos Creek (@ Freedom): 7,400 cfs
Hydrology and Hydraulics
Level of Flood Protection:
Current
Capacity
Pajaro
28,000 cfs
100 Year 50 Year
28,500 cfs
15- Year
1995/199
8 Flood
49,000 cfs
39,600 cfs
25- Year
Salsipuedes
2,400 cfs
6- Year
8,450 cfs
6,750 cfs
Corralitos
3,100 cfs
9- Year
7,350 cfs
6,100 cfs
June 14, 2001
Hydrology and Hydraulics
June 14, 2001
Hydrology and Hydraulics
Insufficient Flood Protection:
June 14, 2001
1995 Floodplain
Hydrology: A Primer
Watershed Area
Total Watershed Area:
1,310 sq. miles
Santa Cruz
County
Monterey 1.5%
Santa Clara
County
Santa
7%
Cruz
Santa 25.5%
Clara
San Benito
County
Monterey
County
San
Benito
66%
June 14, 2001
Hydraulics: A Primer
Capacity Comparison: Existing protection vs 100
year flows
Hydraulics: A Primer
Hydraulics: A Primer
Example Flow Velocity Conditions
Vel. ~ 3 fps
June 14, 2001
Vel. ~ 4-5 fps
Hydraulics: A Primer
Example Flow Velocity Conditions (cont’d)
Vel. ~ 5+ fps
June 14, 2001
Hydraulics: A Primer
Example Flow Velocity Conditions (cont’d)
Vel. ~ 10 fps
Vel. ~ 15 fps
June 14, 2001
Hydraulics: A Primer
Example Pajaro River Channel Conditions
Flood Project Challenges and Opportunities
Project Alternatives—
Peter Cota-Robles
County of Santa Cruz Dept. Public Works
June 14, 2001
Project Alternatives
23 flood protection alternatives studied since 1966
June 14, 2001
Project Alternatives
23 flood protection alternatives studied since 1966
June 14, 2001
Project Alternatives
General Project Alternatives:
(combinations of following elements)
•
•
•
•
•
•
•
•
•
•
June 14, 2001
Elevating Structures
Early Warning System
Dredging & Channel Excavation
Ring Levee for Watsonville & Pajaro
Bypass Channels
Diversion of flood flows to Elkhorn Slough
Retention to upper basin reservoirs
Rebuild/increase height of levees in place
Floodwalls built on top of existing levees
Set-back levees
Consensus Process
23 flood protection alternatives studied since 1966…
• No project
• Set-back
levees
and increase in
levee
height
Community
Concept Plan
• Retention to
upper basin
reservoirs
June 14, 2001
• Bypass
Channels
• Rebuild/increa
se
height of
levees in
place
• Floodwalls
built on top of
existing
levees
Flood Project Challenges and Opportunities
Environmental and
Regulatory
Considerations—
Ken Hart
County of Santa Cruz Planning Dept.
June 14, 2001
Environmental and Regulatory
Goals:
• Identify botanical and wildlife species
that will need to be addressed under
the final plan.
• Identify potential project related
impacts on protected species.
• Create an opportunity to allow for a
proactive approach to project design
relative to biological concerns.
June 14, 2001
Environmental and Regulatory
Final project and operation can result in:



Negative Impacts
Beneficial Impacts
Neutral Impacts (No
Effect)
Environmental and Regulatory
Federal and/or State “special status”
species known to occur within the
Birds
Pajaro
River corridor and• lagoon:
Northern harrier hawk
•
•
•
•
•
•
Yellow warbler
Yellow-breasted chat
White-tailed kite
Saltmarsh common yellowthroat
Willow flycatcher
Great blue heron
•
•
•
•
•
Snowy plover
Double-crested cormorant,
Brown pelican
California least tern
Elegant tern
Fish
•
•
Steelhead trout
Tidewater goby
Amphibians and Reptiles
•
•
•
June 14, 2001
California red-legged frogs
Western pond turtle
Legless lizard
Yellow Warbler
Environmental and Regulatory
Project Design and Operation Potential
Effects On Protected Species
June 14, 2001
Environmental and Regulatory
The distance between the levees can effect the
areas of the river that seasonally contain still
water
Potential Impact to:
• California red-legged frog
• Western pond turtle
June 14, 2001
Environmental and Regulatory
Structures may pose barriers to dispersal of amphibian
and reptile species
Potential Impact to:
• Western pond turtle
June 14, 2001
• Calfornia red-legged
frog
Environmental and Regulatory
Vegetation removal along the river may impact
nesting and foraging areas for birds
Potential Impacts to:






June 14, 2001
Yellow warbler
Yellow-breasted chat
White-tailed kite
Great Blue
Saltmarsh common yellowthroat
Heron
Willow flycatcher
Northern harrier hawk
Northern Harrier Haw
Environmental and Regulatory
Vegetation removal and grading activities could
potentially affect burrowing animals
Potential Impacts to:
 California red-legged
frog
 Western pond turtle
 Legless lizard
June 14, 2001
Environmental and Regulatory
Changes to water velocity may affect steelhead
trout
 Changes to in-stream flow
velocities can affect migration.
 Changes to in-stream flow
velocities can affect channel
configuration and therefore
migration, spawning, and
rearing habitats.
 Channel maintenance,
vegetation removal, and
sedimentation from erosion
may cause changes to
spawning and rearing habitat
(currently above Murphy’s
crossing between river miles 15
to 17.5).
June 14, 2001
Environmental and Regulatory
Changes to water velocity or increased delivery of peak
flows can impact the lagoon environment
LAGOON SPECIES
 Steelhead trout
 Tidewater goby
DUNE AND BEACH SPECIES
• Legless lizard
NESTING SPECIES
• Western snowy plover
NON-NESTING SPECIES (ONLY KNOWN TO ROOST
OR FORAGE WITHIN THE PAJARO LAGOON)
• Double-crested cormorant
• Brown pelican
• Great blue heron
• California least tern
• Elegant tern
June 14, 2001
Environmental and Regulatory
Potential project plan and alternatives must
consider:
Endangered and
Threatened
Species & Habitat

June 14, 2001
Environmental and Regulatory
Informal Consultation with key environmental
agency representatives is an essential element of
this process…

Monterey and Santa Cruz Counties

California Fish & Game

Coastal Commission

Regional Water Quality Control Board

US Fish & Wildlife Service

National Marine Fisheries Service

Monterey Bay National Marine Sanctuary
Individuals From The Above Are Invited To:
Association of Monterey Bay Area Governments

1.
2.
June 14, 2001
COE Scoping Process (begins June 21)
Focus Group w/ MIG
Flood Project Challenges and Opportunities
Socio-Economic
Considerations—
David Koch
City of Watsonville, Dept. Public Works
June 14, 2001
Socio-economic Considerations
Framework for evaluation of plan
alternatives:

Flood Protection

Agricultural Land Impacts

Business Impacts

Residential Impacts

Visual Impacts

Recreation

Economic Development
Socio-Economic Considerations

June 14, 2001
Agricultural acres

Residential acres

Commercial acres
Socio-Economic Considerations
Costs of Damages associated with
flooding:

Total Cost of 1995 Flood Damage –
$95 Million
Total Value of Existing Land in
Floodplain – $1 Billion

Source: US Army Corps of
Engineers
June 14, 2001
Socio-Economic Considerations
Agricultural Land
Implications


Business Implications

Residential Implications

Visual Impacts

Recreation

Economic Development

Public Safety
June 14, 2001
Socio-Economic Considerations

Agricultural Land Implications

Business Implications

Residential Implications

Visual Impacts

Recreation

Economic Development

Public Safety
June 14, 2001
Socio-Economic Considerations

Agricultural Land Implications

Business Implications

Residential Implications

Visual Impacts

Recreation

Economic Development

Public Safety
June 14, 2001
Socio-Economic Considerations

Agricultural Land Implications

Business Implications

Residential Implications

Visual Impacts

Recreation

Economic Development

Public Safety
June 14, 2001
Socio-Economic Considerations

Agricultural Land Implications

Business Implications

Residential Implications

Visual Impacts

Recreation

Economic Development

Public Safety
June 14, 2001
Socio-Economic Considerations

Agricultural Land Implications

Business Implications

Residential Implications

Visual Impacts

Recreation

Economic Development

Public Safety
June 14, 2001
Socio-Economic Considerations

Agricultural Land Implications

Business Implications

Residential Implications

Visual Impacts

Recreation

Economic Development

Public Safety
June 14, 2001
Flood Project Challenges and Opportunities
Financial Feasibility—
David Dickson, MIG,
Inc.
June 14, 2001
Financial Feasibility
June 14, 2001

Federal Authorization

Federal/Local Cost Sharing

Local Share of Cost

Who pays for local share of cost ?

Sources of Local Share-external

Project Maintenance
Financial Feasibility
Federal Authorization:

Flood Control Act of 1966

WRDA of 1986

Favorable Cost Sharing
Federal Cost Share: 75%
down to 50%

•Local cost share: 25%
minimum but
cannot
exceed 50%
• Additional Authority Needed
for
June 14, 2001
Financial Feasibility
Cost Sharing for Hypothetical $100
Channel Work Intensive
million Project
Local Cost
Land
Bridges/Utilities
5 % Cash
TOTAL LOCAL
$10
$15
$5
$30 million*
Federal Cost
Levees/Walls
Channel Work
Railroad Bridges
Fish & Wildlife
Planning
Subtotal
5% Cash from Locals
TOTAL FEDERAL
$40
$15
$5
$10
$5
$75 million
{ 5}
$70
*State Subventions reimburses up to 70%
June 14, 2001
“Betterments”-100%
Local
Financial Feasibility
Cost Sharing for a Hypothetical $100
Land and Bridgemillion
Intensive Project
Local Cost
Land
Bridges/Utilities
5% Cash
Fed Reimbursement
TOTAL LOCAL
Federal Cost
Levees/Walls
Channel Work
Railroad Bridges
Fish & Wildlife
Planning
Subtotal
Reimburse Locals
TOTAL FEDERAL
$30
$25
$ 5
{$10}
$50 million*
$15
$5
$5
$10
$5
$40 million
$10
$50 million
*State Subventions reimburses up to 70%
June 14, 2001
Financial Feasibility
Sources of Local Share
Santa Cruz County Zone 7
Flood District
Annual revenue - $1,200,000
year
Existing assessment rates:
$ 53
per year for homes
$ 7.35 per acre for farm
land
$ 353.38 per acre for
industrial/
commercial
All revenues committed to
June 14, 2001
Financial Feasibility
Sources of Local Share
MONTEREY COUNTY WATER RESOURCES AGENCY
PAJARO LEVEE ZONES 1 & 1A
June 14, 2001
Financial Feasibility
Sources of Local Share
Monterey County Water
Resources Agency
ZONES 1 & 1A
June 14, 2001
• Annual revenue - $300,000
• Existing assessment rates:
• $ 61 per acre for farm land and
homes
• $244 per acre for industrial,
commercial and institutional
land
• Increasing assessments will be a
challenge
Financial Feasibility
Sources of Local Share
Prop 218: How Benefit Assessments may be
levied:
• Requires 50 % vote of landowners being
assessed (weighted vote) or 2/3 of Electorate in
area to be assessed, and
• Requires nexus between amount paid and direct
benefit received
Special Tax: Sales Tax, Ad Valorum, etc = 2/3
of Voters
June 14, 2001
Financial Feasibility
Sources of Local Share
Outside Sources:
• CALTRANS HBRR
• Land already owned
• Prop 13 Water Bond-various
programs
• Wildlife Conservation Board
• California Coastal
Conservancy
• State Lands Commission
• Private Foundations
• EPA Water Quality Programs
June 14, 2001
Consensus Process
Three possible planning processes…
OUTCOME
Possible
Outcome
I
Complete Consensus
All members of the Stakeholder group are in
agreement with everything.
RESULT
Flood
Project
Likely
Classic Consensus
Possible
Outcome
II
A. I agree with most of the recommendations
and I am willing to support all of them.
B. I agree with many of the recommendations
and I will not oppose them.
C. I do not agree with the recommendations
but I will not actively oppose them.
Minority & Minority Reports
Possible
Outcome
III
June 14, 2001
A. Number of members who agree.
B. Number of members who do not agree.
C. Number of members who abstain.
Flood
Project is
Possible
High Risk of
No Action
Stakeholder Meeting #1
June 14, 2001
Hydrology and Hydraulics
What’s the difference?
Hydrolog
y
Hydraulic
s
General
definition…
The study of
the
hydrosphere.
The study of
fluid motion.
In flood
damage
reduction
planning
and
design….
Computatio
The estimation of
flood flow rates
under various
watershed and
precipitation
conditions.
The estimation of
water surface
elevations, flow
depths, and velocities
in the stream channel
based on channel
shape, size, and
Computer
modeling
hydraulic roughness.
and comparison to
observed floods.
n
methods….
June 14, 2001
Statistical analysis
of gage records and
computer modeling.
Hydrology: A Primer
Hydrologic Investigations
Statistical analysis of gage records and computer
models are frequently used to estimate runoff rates,
volumes, and timing.
Typical Results:
Source Data:
• Streamflow gage
data
• Rainfall gage data
• Watershed
Characteristics
• Land Use
Practices
• Soil
Characteristics
• Etc…
June 14, 2001
•
Statistical
Analysis
and/or
Modeling
•
•
Estimate of peak rate of
runoff, in cubic feet per
second (cfs).
Estimate of volume of
runoff, in acre-feet (af)
Estimate of timing of
runoff, including how
runoff from various
sub-areas and streams
combine (shown as a
hydrograph)
Hydrology: A Primer
Example Hydrologic for Pajaro River
1998 Pajaro River Historical Flood Flows
1998 Pajaro River Historical Flood
Flows
Flowrate
in “cfs”
30,000
Area under curve is the
volume of runoff from
the storm
Flow Hydrograph
20,000
15,000
10,000
5,000
Duration (by Date)
Pajaro R. @ Chittenden Gage
8
-M
ar
-9
-M
ar
Time to runoff
or “duration”
26
16
-9
8
8
6-
M
ar
-9
8
-F
eb
-9
24
14
-F
eb
-9
8
8
Fe
b9
4-
-J
an
-9
8
0
25
Flowrate (cfs)
25,000
Hydraulics: A Primer
Hydraulic Investigations
A computer model is frequently used to estimate
flow depths and velocities, and to determine
floodplains. The model can then be used to study a
variety of alternatives, including different channel
configurations and level of vegetation or roughness
Source Data:
• Peak flow rate, cfs
• Channel geometry
(shape and size)
• Roughness
(usually depicts inchannel vegetation,
surface treatment,
sediment buildup,
etc.)
• Flood control
features (levees;
gates or weirs;
etc.)
June 14, 2001
Typical Results:
Hydraulic
Model
• Estimate of flow velocity, in
fps.
• Estimate of flow depth, in
feet (usually presented as a
water surface profile and/or
floodplain map).
• Estimate of flood
conveyance capacity, in
cfs)
Hydraulics: A Primer
Example Hydraulic Study Results for
Pajaro River