Alluvial Fans and Regulated Land
Use Planning
Alluvial Fan Task Force
Plenary Meeting 8
Presentation by:
Boykin Witherspoon III, Director
Center for Geographic Information Science Research,
California State Polytechnic University Pomona
(909) 869-6913, bwitherspoon@csupomona.edu
Professor Jon Nourse &
Sean Carlson, Chris McCarthy
Graduate Assistants, CalPoly, Pomona
Technical Consultants to the
Alluvial Fan Task Force
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Cal Poly Pomona
Center for Geographic Information Science Research
Fundamental Issue
Why is there a problem? What are these types of ordinances trying to really do?
The issue fundamentally comes down to land classification units (LCU’s), the ones that
define regulated jurisdictions are different than the ones that define natural processes.
Tectonic
Elevation
Temperature
Ecosystem
Watershed
Sub-basin
City
County
State
Country
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Cal Poly Pomona
Center for Geographic Information Science Research
This is how we
Measure
hazard
This is how we
measure
Vulnerability,
this how most
of our
ordinances are
applied to
locations on the
ground.
Fundamental Issue
This is the polygonal geometry we
use to assess fan related hazard
This is the polygonal and line
geometry we use to assess
earthquake hazard
These are curvilinear land classification units (LCU’s)
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Cal Poly Pomona
Center for Geographic Information Science Research
Fundamental Issue
This is the
polygonal geometry
we subjectively, self
assign as
jurisdictions for our
ordinances
These are rectilinear land
classification units (LCU’s)
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Cal Poly Pomona
Center for Geographic Information Science Research
Fundamental Issue
WOW
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Cal Poly Pomona
Center for Geographic Information Science Research
Fundamental Issue
So this LCU pattern is
self made by us and
represents, well
nothing but our
collective will.
Why do we go with our
collective will, against the rules
of nature and then mitigate /
engineer away a million years of
reality?
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And this pattern is
created by nature over
millions of years and
represents the reality of
the hazards we face.
Cal Poly Pomona
Center for Geographic Information Science Research
Fundamental Issue
What we are suggesting is,
“lets change our collective plan view
aesthetic of what jurisdictional land class
units look like so that that they match
reality.”
We are working way to hard and spending way to much money
engineering and mitigating when we could just be paying more
attention to reality.
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Cal Poly Pomona
Center for Geographic Information Science Research
An Example from Homer Alaska
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Cal Poly Pomona
Center for Geographic Information Science Research
An Example from Homer Alaska
http://www.suitabilitymap.org/
Products and Schedule:
This project is scheduled to be completed in August
2008 is divided into three interrelated products:
1. A GIS-based, landscape-level, suitability map will
identify core conservation areas to be prioritized for
protection, recognize areas highly suitable for
development and recognize areas that would benefit
from preserving landscape systems in their
development. A first rendition to be completed in
September 2007.
2. Launch a developer certification program built around
the suitability map to train and influence developers
(of any size projects) to incorporate landscape
systems into their designs. The pilot certification
program is tentatively scheduled for June 2008.
3. Identify and incorporate incentives that encourage
developers to become certified and reduce the costs
associated with best management practice
implementation. Ideally, the incentives identified will
create situations where the bottom line of any
development project will be more profitable. The
initial list of possible development guidelines and
incentives will be completed in October 2007.
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“Development interests and
regulations are built primarily
around parcel boundaries, and
are therefore not guided by larger
landscape patterns. Landscape
systems cross parcel boundaries,
and as a result, valuable
functional and aesthetic qualities
are often sacrificed when an
individual parcel is developed
without regard to these systems.
This piecemeal development
leads to loss of functional and
economic value and creates longterm public expense.”
Cal Poly Pomona
Center for Geographic Information Science Research
An Example from Homer Alaska
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Cal Poly Pomona
Center for Geographic Information Science Research
AF1
1st we determine
the footprint of the
fan
go
halt
How do we do that?
AF2
AF3
go
halt
2nd we determine
the location of the
fan hazards
FH1
5th we use our Geographic
Information Science to pull
all of the data together and
turn it into Land Class Units
based on science and
reality
FH2
FH3
To
finish
go
halt
To
finish
MA1
go
3rd we determine
the locations of a
bunch of other
hazards
MH1
Multi
MH2
MH3
MH4
MH5
MH6
To
finish
th
6 we look at what we have
done in the past that works
and meets multiple
objectives and then we use
the relationship between
reality on the ground and
what works to either:
Preemptively create a new
zoning ordinance
To
finish
MA2
SDT
go
MB1
To
finish
MA4
Multi
MB2
DC1
MB3
DC2
MB4
Finished
Draft model
Ordenance
MB5
Prelim
design and /
or draft EIR
MB6
4th we find the
locations of all the
good things about
the fan
MB7
Eng
Mitigati
on
A.
go
halt
None
Multi
MA3
finish
FM4
ECO1
ECO1
ECO2
B.
Or do a design / EIR based
on science and reality
ECO3
ECO4
ECO4
ECO5
ECO5
ECO6
ECO6
ECO7
ECO7
Draft
Feasibility
Report
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7th is to evaluate
what we are
proposing against
protections needed
and economic
viability.
Cal Poly Pomona
Center for Geographic Information Science Research
May 19, 2000 Raising the Roof, California's Housing Development Projections and Constraints, 1997-2020.
MB7
Pro Development model
New AFTF tool
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Cal Poly Pomona
Center for Geographic Information Science Research
Quick look at how the MA1-4 tools work
Earthquake shaking potential
(California Geological Survey)
Map 5.4.1H. Earthquake Hazard
Average Raster value score for
Shaking Potential PGA
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Cal Poly Pomona
Center for Geographic Information Science Research
Quick look at how the MA1-4 tools work
Map 5.4.1H. Earthquake Hazard
Map 5.4.1C. Total/Vulnerable
Population
Weighted
combination
Vuln Pop
50%
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Map 5.4.1D. Earthquake Hazard and
Total/Vulnerable Population
EQ Haz
50%
1
2
3
1
1
2
2
2
2
2
3
3
2
3
3
Cal Poly Pomona
Center for Geographic Information Science Research
Traditional Minimum Ordinance
Administrative Work Flow
for Project Review
Has the appropriate level
of protection been met
This workflow represents the
minimum method recommended in
the draft ordinance beginning with a
draft EIR being submitted to the
administrator. The AFTF tools are
used primarily in a review capacity
by a public administrator to create a
administrative report to the
governing body responsible for
approving proposed developments.
This line represents the
minimum
Also part of
the 5.1 review
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Cal Poly Pomona
Center for Geographic Information Science Research
Alluvial Fans and Regulated Land Use Planning
Thank You
Presentation by:
Boykin Witherspoon III, Director
Center for Geographic Information Science Research,
California State Polytechnic University Pomona
(909) 869-6913, bwitherspoon@csupomona.edu
Professor Jon Nourse &
Sean Carlson, Chris McCarthy
Graduate Assistants, CalPoly, Pomona
Technical Consultants to the
Alluvial Fan Task Force
C G
I
S R
Cal Poly Pomona
Center for Geographic Information Science Research