REPORT FOR CONSULTATION ON THE
PORTLAND INTERSTATE
AIR QUALITY CONTROL REGION
(OREGON-WASHINGTON)
U. S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE
Public Health Service
Environmental Health Service
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95OR7OOO2
REPORT FOR CONSULTATION ON THE
PORTLAND INTERSTATE
AIR QUALITY CONTROL REGION
( OREGON-WASHINGTON)
u. S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE
Public Health Service
Consumer Protection and Environmental Health Service
National Air Pollution Control Administration
March, 1970
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CONTENTS
PREFACE i
INTRODUCTION 1
EVALUATION OF URBAN FACTORS 11
EVALUATION OF ENGINEERING FACTORS 30
THE PROPOSED REGION 56
DISCUSSION OF PROPOSAL 56
REFERENCES 62
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PREFACE
The Air Quality Act of 1967 directs the Secretary of Health,
Education, and Welfare to designate "air quality control regions"
to provide a basis for the adoption of regional air quality
standards and the implementation of those standards.
The Act stipulates that the designation of a region shall
be preceded by consultation with appropriate State and local
authorities. This report is intended to serve as background
material for the consultation. It proposes boundaries for the
Portland Interstate Air Quality Control Region and discusses
the factors which are the basis of the boundary proposal.
The Region* boundaries proposed in this report reflect
consideration of available and pertinent information. However,
the proposed boundaries remain subject to revisions suggested
during consultation with State and local authorities. Formal
designation of a Region will be made only after a careful review
of all opinions and suggestions submitted during the consultation
process.
The National Air Pollution Control Administration (NAPCA)
appreciates assistance received from the State and regional
air pollution control programs of Oregon and Washington, and the
county and regional planning agencies in the Study Area.
*For the purpose of this report, the word "region" when capitaliced,
will refer to the Portland Interstate Air Quality Control Region.
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INTRODUCTION
THE REGIONAL APPROACH
Air pollution in the urban areas of the United States is
a regional problem which frequently extends across State and
local governmental boundaries. Since air pollution problems
are rarely confined to any single municipality or county, successful
control requires coordinated planning, standard setting, and
enforcement by the several political jurisdictions which share
a common problem. At the present, State and local governments
across the Nation have only begun to develop a regional approach
to air pollution control.
The Clean Air Act as amended provides a regional approach
which depends upon coordination and cooperation between all
levels of government: municipal, county, State and Federal.
To set in motion the machinery for regional air pollution control,
the Department of Health, Education, and Welfare first designates
air quality control regions, issues air quality criteria, and
publishes reports on control techniques. The region designation
Indicates which State and local jurisdictions will be involved
in a regional air pollution control effort. The air quality
criteria indicate the extent to which various concentrations of
an air pollutant are harmful to health and damaging to property.
The reports on control techniques provide information on the
costs and effectiveness of various techniques for controlling air
pollutant emissions.
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After the Department of Health, Education, and Welfare
completes these initial steps, State governments develop air
quality standards and plans for implementation of those
standards for portions of air quality control regions within
their boundaries. An air quality standard defines the desired
limit on the concentration of a pollutant in the ambient air
of the region. It constitutes the degree of air quality which
the regional control program will attempt to achieve. An
implementation plan is a blueprint of the steps which will be
taken to insure achievement of the air quality standards
within a reasonable time. The Governors have 90 days to
submit letters indicating that they intend to set standards,
180 days in addition to set the standards, and 180 days further
to develop plans for implementing them. The procedure for
setting standards Includes a public hearing which allows
residents of a region to express their views concerning desired
standards.
The Department of Health, Education, and Welfare reviews
air quality standards and implementation plans in order to
ascertain their consistency with the provisions of the Clean
Air Act as amended.
When air quality standards and implementation plans are
approved, States proceed to prevent and control air pollution
in accordance with those standards and plans. This system for
establishing a regional approach to air pollution control is
depicted in the flow diagram in Figure 1.
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HEW DESIGNATES
AIR QUALITY
CONTROL REGIONS.
HEW DEVELOPS AND
PUBLISHES AIR
QUALITY CRITERIA
£ASED ON'SCIENTIFIC
EVIDENCE OF AIR
POLLUTION EFFECTS.
HEW PREPARES
AND PUBLISHES
REPORTS ON
AVAILABLE CONTROL
TECHNIQUES
STATES INDICATE
THEIR INTENT
TO SET STANDARDS.
(PUBLIC
HEARINGS)
STATES SET
AIR QUALITY
STANDARDS
FOR THE AIR
QUALITY CONTROL
REGIONS.
I
STATES SUBMIT
STANDARDS FOR
HEW REVIEW.
STATES ESTABLISH
COMPREHENSIVE PLANS
FOR IMPLEMENTING
AIR QUALITY
STANDARDS.
STATES SUBMIT
IMPLEMENTATION PLANS
FOR HEW REVIEW.
STATES ACT TO CONTROL
AIR POLLUTION IN ACCORDANCE
WITH AIR QUALITY STANDARDS
AND PLANS FOR IMPLEMENTATION.
u»
Figure 1 FLOW DIAGRAM FOR ACTION TO CONTROL AIR POLLUTION ON A REGIONAL
BASIS, UNDER THE AIR QUALITY ACT.
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DESIGNATION OF AIR QUALITY CONTROL REGIONS
Designation of an air quality control region is one of the
first steps in the regional approach to air pollution control.
Section 107(a)(2) of the Clean Air Act as amended directs the
Secretary, Department of Health, Education, and Welfare to make
such designations. The portions of the section relevant to
this discussion state:
''...The Secretary, after consultation with
appropriate State and local authorities shall...
designate air quality control regions based on
jurisdictional boundaries, urban-industrial con-
centrations, and other factors including atomspheric
areas necessary to provide adequate implementation
of air quality standards. The Secretary may...
revise the designation of such regions... The Secretary
shall immediately notify the Governors of the affected
State or States of such designation."
The Size of a Region
As stipulated in Section 107(a)(2), the designation of
air quality control regions should be based on "jurisdictional
boundaries, urban-industrial concentrations, and other factors
including atmospheric areas necessary to provide adequate
Implementation of air quality standards." This language suggests
a number of objectives which are important in determining how
large an air quality control region should be. Basically, these
objectives can be divided into three separate categories.
First, a region should be self-contained with respect to
air pollution sources and receptors. In other words, a region
should include most of the important sources in the area as
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well as most of the people and property affected by those sources.
Unfortunately, since air pollutants can travel long distances,
it is impractical if not impossible to delineate regions which
are completely self-contained. The air over a region will usually
have at least trace amounts of pollutants from external sources.
During episodic conditions, such contributions from external
sources may even reach significant levels. Conversely, air
pollution generated within a region and transported out of it
can affect external receptors to some degree. It would be
impractical and inefficient to make all air quality control
regions large enough to encompass these low-level trace effects.
The geographic extent of trace effects overestimates the true
problem area which should be the focus of air pollution control
efforts. Thus, the first objective, that a region be self-
contained, becomes a question of relative magnitude and frequency.
The dividing line between "important influence" and "trace
effect" will be a matter of judgment. The judgment should be
based on estimates of the impact a source has upon a region
and the level of pollution to which receptors are subjected.
In this respect, annual and seasonal data on pollutant emissions
and ambient air concentrations are a better measure of relative
influence than short term data on episodic conditions. The
second general objective requires that region boundaries be
designed to meet not only present conditions but also future
conditions. In other words, the region should include areas
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where Industrial and residential expansion are likely to create
air pollution problems in the foreseeable future. This objective
requires careful consideration of existing metropolitan development
plans, expected population growth, and projected industrial
expansion. Such considerations should result in the designation
of regions which will contain the sources and receptors of
regional air pollution for a number of years to come. Of course,
region boundaries need not be permanently fixed, once designated.
Boundaries should be reviewed periodically and altered when
changing conditions warrant readjustment.
The third objective is that region boundaries should be
compatible with and even foster unified and cooperative governmental
administration of the air resource throughout the region. Air
pollution is a regional problem which often extends across
several municipal, county, and even State boundaries. Clearly,
the collaboration of several governmental jurisdictions is
prerequisite to the solution of the problem. Therefore, the
region should be delineated in a way which encourages regional
cooperation among the various governmental bodies involved in
air pollution control. In this regard, the existing pattern
of governmental cooperation on the whole range of urban problems
may become an important consideration. Certainly the pattern
of cooperation among existing air pollution control programs
is a relevant factor. In general, administrative considerations
dictate that governmental Jurisdictions should not be divided.
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Although it would be impractical to preserve State jurisdictions
undivided, usually it is possible to preserve the unity of county
governments by including or excluding them in their entirety.
Occasionally, even this would be impractical due to a county's
large size, wide variation in level of development, or striking
topographical features.
To the extent that any two of the above three objectives
lead to incompatible conclusions concerning region boundaries,
the region must represent a reasonable compromise. A region
should represent the best way of satisfying the three objectives
simultaneously.
Procedure for Designation of Regions
Figure 2 illustrates the procedures used by the National
Air Pollution Control Administration for designating air quality
control regions.
After evaluating relevant engineering factors and urban
factors, the National Air Pollution Control Administration
publishes a proposed delineation of the region boundaries. At
the same time NAPCA sets a time and place for a consultation
meeting and distributes to State and local authorities a report
of the evaluation study which includes the boundary proposal.
At the consultation meeting State and local authorities are
encouraged to present fully their views and suggestions concerning
the proposed boundaries of the region. Interested parties who
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ENGINEERING EVALUATION
• EMISSIONS INVENTORY
• TOPOGRAPHY
• METEOROLOGY
• AIR QUALITY ANALYSIS
EXISTING AIR QUALITY DATA
DIFFUSION MODEL OUTPUT
URBAN FACTORS EVALUATION
• JURISDICTIONAL BOUNDARIES
• URBAN-INDUSTRIAL CONCENTRATIONS
• COOPERATIVE REGIONAL ARRANGEMENTS
• PATTERNS AND RATES OF GROWTH
• EXISTING STATE AND LOCAL AIR POLLUTION
CONTROL PROGRAMS & LEGISLATION
PRELIMINARY
DELINEATION
OF REGIONS
CONSULTATION
WITH STATE AND
LOCAL OFFICIALS
H
FORMAL
DESIGNATION BY
SECRETARY-HEW
Figure 2. FLOW DIAGRAM FOR THE DESIGNATION OF AIR QUALITY CONTROL REGIONS.
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do not have official status may submit comments in written form
for the record. After careful review of all suggestions and
opinions submitted for the record by interested parties, the
Secretary of Health, Education, and Welfare makes a formal
designation of the region boundaries and notifies the Governors
of the designation.
As noted above, the evaluation of relevant engineering
factors and urban factors forms the basis of the boundary
proposals published by NAPCA. The evaluation of engineering
factors is designed to indicate the location of pollution sources
and the geographic extent of serious pollutant concentrations
in the ambient air. Pollution sources are located by taking an
inventory of emissions from automobiles, industrial activities,
space heating, waste disposal, and other pollution generators.
The transport and distribution of pollutants in the ambient air
are analyzed on the basis of measured air quality data, the
location of emissions, meteorological data, and topographic
information. A mathematical diffusion model which predicts
ambient pollution concentrations from information on emissions
and meteorology can be used in areas where irregular topographical
features would not invalidate the theoretical model. As a
whole, the engineering study indicates how large the air quality
control region must be in order to encompass most pollution
sources and most people and property affected by those sources.
The study of urban factors encompasses non-engineering
considerations. It reviews existing governmental jurisdictions,
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10
the location of urban and industrial concentrations, expected
patterns of urban growth, cooperative regional arrangements,
existing State and local air pollution control programs, and
other associated factors. As a whole, the study of urban factors
is designed to indicate how large a region must be in order to
encompass expected regional growth and to encourage cooperation
among political units in controlling air pollution.
The body of this report contains a proposal for the boundaries
of the Portland Interstate Air Quality Control Region and outlines
the evaluation of engineering and urban factors which were the
basis of the proposal. The report is intended to serve as the
background document for the consultation with appropriate State
and local officials.
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11
EVALUATION OF URBAN FACTORS
INTRODUCTION
A number of urban factors are relevant to defining air
quality control region boundaries. Since human activity is the
primary cause of air pollution, and humans are the ultimate
victims, the location of population is an important consideration.
The projected population growth pattern is another important
consideration, since an air quality control region should be designed
not only for the present but also for the future. Political
and jurisdictional considerations are important since the Clean
Air Act envisions regional air pollution programs based on
cooperative efforts among many political jurisdictions. The
following discussion of urban factors will present these con-
siderations as they apply to the Portland area.
REGIONAL SETTING
Portland, Oregon, lies at the confluence of the Columbia
and Willamette Rivers in northwest Oregon. Other major cities
in the area include Vancouver, Washington, located across the
Columbia River from Portland, Kelso-Longview, Washington, lying
north of Portland on the Columbia, and Salem and Eugene, Oregon,
which lie south of Portland in the Willamette Valley. For the
purposes of this study, a fifteen-county "study area" was
chosen. The Study Area includes the counties of Columbia, Washington,
Multnomah, Yamhill, Clackamas, Polk, Marion, Benton,
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12
Linn, and Lane, in Oregon, and Clark, Cowl it z, Wahkiakum,
Skamania, and Lewis Counties in Washington. These counties
were chosen on the basis of urbanization, regional planning
and air pollution control arrangements, topography, and other
factors which would indicate a close tie between the Portland
metropolitan area and the surrounding counties. The Study Area
counties lie in northwest Oregon and southwest Washington, in
the valleys formed by the Columbia and Willamette Rivers.
The Portland Standard Metropolitan Statistical Area (SMSA)*
consists of Clackamas, Multnomah, and Washington Counties in
Oregon, and Clark County, Washington. Marion and Polk Counties
comprise the Salem SMSA, and Lane County comprises the Eugene
SMSA. Figure 3 outlines the Study Area and the Portland, Salem,
and Eugene SMSA's. Also shown is part of the Seattle SMSA,
which lies outside the Study Area.
The Puget Sound Air Quality Control Region, consisting of
Snohomish, King, Pierce, and Kitsap Counties in Washington,
was officially designated by the Secretary of Health, Education,
and Welfare, In 1969.
*SMSA's are defined by the Bureau of the Census and other Federal
agencies for use in publishing census data and a variety of other
government statistics. An SMSA is composed of one county or a
group of contiguous counties which contain at least one central
city of 50,000 inhabitants or more or twin-cities with a combined
population of at least 50,000. In addition, other contiguous counties
are included In an SMSA if, according to certain criteria, they
are essentially metropolitan in character and are socially and
economically integrated with the central city.
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••:;.;•'.•-.:•. Sal era SMSA :
'• •:.'• :•-:':S''•••.'•:• '•:^•''-;•':•:. •>•.
•..' -.' pf)L If •'•'•''' '• V • •'• '• •' fs
•••IIB Boundary of
Study
Figure 3. Portland Region Study Area and
Standard Metropolitan Statistical Areas.
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14
POPULATION
Within the fifteen-county Study Area, six counties have
populations of over 100,000 residents. The metropolitan Portland-
Vancouver area is centered in four of these counties—Multnomah
(population, 552,000), Clackamas (population, 149,000), Washington
(population, 136,000), and Clark (population, 114,000). Marion
County contains the city of Salem and has a population of 155,000.
Separated from this core of five counties is Lane County (population,
212,000) , which contains the city of Eugene and has the largest
land area in the Study Area. The 1969 population is shown in
Figure 4 and in Table I.1
By population density (1969), Figure 5, Multnomah County
is again shown to be the center of population in the Study Area
with a density of 1310 residents per square mile. Washington,
Clark, and Marion Counties follow with densities of between
100 and 200 residents per square mile. The remaining counties
in the Study Area have population densities of less than 100
residents per square mile.
Population projections by county in the Study Area have been
made by the Oregon State Board of Census and the Washington State
Census Board and by several regional planning agencies.2»3»4»5,6,7
Table 1 presents population projections for 1980. Figures 6
*Where more than one projection was available, the projected 1980
population which most nearly conformed to an extrapolation of
the growth from 1960-1969 was chosen. In the case of three counties
(Benton, Linn, and Yamhill), only one set of projections was
available, and based on the growth from 1960-1969, the projections
were clearly in error. In these cases, it was assumed that growth
from 1960-1980 would continue at the same rate as from 1960-1969.
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Residents per county
| > 200,000
100,000-*-200 ,000
50,000—100,000
< 50,000
Figure 4. Population by County in the
Portland Area.(1969)
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16
Table I. Population Data for the Portland Study Area
County
Bent on
eClackamas
0 Columbia
Lane
•Linn
„ Marion
Multnomah
*• Polk
0 Washington
Yamhill
B Clark
S Cowllta
£ Lewis
3 Skamania
5 Wahklakum
Area
mi.2
668
1884
639
4562
2290
1166
422
736
716
711
627
1144
2449
1672
261
Pop. I9601
39,165
113.038
22,379
162,890
58.867
120.888
522.813
26,523
92,237
32,478
93,809
57,801
41,858
5,207
3,426
Pop. Den.
1960
res. /mi.
59
60
35
35
26
104
1235
36
129
46
149
50
17
3
13
Pop. 1969*
48,600
149,000
27,000
212,000
68,700
155,000
552,000
35,000
136,000
41,200
114,000
64,000
43,000
5,900
3,200
Pop. Den.
1969
res. /mi.2
73
79
42
46
30
133
1310
48
190
58
182
56
18
4
12
-!$•
60,000«
202,100*
32,200*
274,337"
80, 900?
196,000*
640,400'
49,000*
179,600*
52,000'
166,000"
76,908C
50,669*
7,097f
4,141f
, Projected
Pop. Den.
1980
res. /mi.2
90
107
50
60
35
168
1522
67
251
73
265
67
21
4
16
Projected
Abs. Bop.
Growth
1960-1980
20,835
89,062
9,821
111,447
22,033
75,112
118,587
22,477
87,363
19,522
72,191
19,107
8,811
1,890
715
Projected
Pop. Growth
1960-1980
Add. res. /mi.2
31
47
15
25
9
64
287
31
122
27
116
17
4
1
3
Projected
Pop. Growth
1960-1980
X
53X
78X
43X
71X
35X
62X
23X
86X
95X
59X
78X
34X
24X
36%
23X
* Metropolitan Planning Coomission
D Central Lane Planning Council
c Cowlitx Regional Planning Commission
d Mid-Willamette Valley Council of Governments
* Linear Projection Based on 1960 and 1969 Population Data
£ Washington State Census Board
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Resldants per odL.
Figure 5 . Population Density
by County, 1969.
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18
and 7 shew projected population growth, 1960-1980, by county in
the Study Area. By absolute population growth, Figure 6, it is
evident that most of the growth will occur in the Portland-Vancouver
metropolitan area, especially in Multnomah County, and around the
City of Eugene in Lane County. Washington, Clark, Clackamas,
and Marion Counties are expected to have grown by 50,000 to 100,000
residents between 1960 and 1980.
Figure 7 shows growth from 1960-1980, expressed in additional
residents per square mile. Again, the metropolitan Portland-
Vancouver area is expected to register the most growth in population
density. Multnomah County is projected to add over 200 residents
per square mile, and Washington and Clark Counties, between 100
and 200. Marion County is projected to register a growth of 64
additional residents per square mile, between 1960 and 1980.
In summary, there are three distinct centers of present
population in the Study Area, and these same areas are projected
to show the major growth in the next decade. The counties
involved in this growth are Multnomah, Clark, Washington, Clackamas,
Marion, and Lane. These six counties contain over 1,300,000
people and comprise over 80% of the population in the fifteen-county
Study Area.
AIR POLLUTION CONTROL PROGRAMS
The Oregon Revised Statutes, Chapter 449, provides the
legal authority for air pollution control in the State of Oregon.
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Additional Residents
per County, 1960-1980
|Xoo,ooo
30,000--100,000
10,000—50,000
Figure 6. Projected Population Growth, 1960-1980,
of the Study Areq Count-<«.« (See
References 1 through 7)
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A^ditloraL'i Residents
|>aoo
lOOw-fcfX*
50—100
as
Projected Population Density Growth
of the Study Area Gai|#^Bg^. li^wso
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21
Under the Statutes, authority is vested with the five-member
Environmental Quality Commission within the Department of
Environmental Quality, and the Regional Air Quality Control
Authorities. Among the duties of the Commission are the following:
developing a comprehensive plan for the control of air pollution
in the State, determining the degree of air pollution in various
areas of the State, conducting research, developing demonstration
programs with local communities, providing technical services
to local communities, and enforcing the Statutes relating to
air pollution. The Environmental Quality Commission also has
the power to set air purity standards for different areas of the
State, to set air quality standards for the entire State or areas
thereof, to adopt rules and regulations for the prevention of
air pollution, to adopt emission standards, and to grant variances.
There are several contaminant sources which are exempted
from control under the Statutes, including agricultural operations,
residential barbecue equipment and agricultural land-cleaning
operations, certain residential heating equipment, and fires set
by public officers in connection with weed-burning, civil defense
or fire-fighting instruction, or prevention of a fire hazard.
The Regional Air Quality Control Act of 1967 provided for
the establishment of regional air quality control authorities.
After the authority is established, it assumes the responsibilities
of the Sanitary Authority functions relating to powers and duties,
rules and regulations, and enforcement. The regional authority
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22
has exclusive control within its jurisdiction except for the
sources whose control is retained by the State. These include
chemical pulp and paper industry, nuclear power generation,
motor vehicles, aluminum reduction and agricultural field-burning.
No regional authority may adopt a rule or standard which is
less stringent than a rule or standard of the Environmental Quality
Commission.
Three such regional authorities have been established under
the Act. The Columbia-Willamette Air Pollution Authority,
established in January*1968, covers the counties of Clackamas,
Columbia, Washington, and Multnomah Counties. The Mid-Willamette
Valley Air Pollution Control Authority was formed in October,
1967, by joint agreement of the governing bodies of Marion, Polk,
Yamhill, Linn, and Benton Counties. The Lane Regional Air Pollution
Authority has control authority throughout Lane County. Figure
8 shows the boundaries of the regional jurisdictions, including
the Southwest Air Pollution Control Authority in Washington.
The Washington Clean Air Act of 1967 established, within
the State Department of Health, an Air Pollution Control Board
which is composed of nine members appointed by the Governor.
Among the duties assigned to the Board by the 1967 Act were the
responsibilities to adopt and enforce air quality goals and
emission regulations, to monitor air quality, and to'give technical
assistance to local programs within the State. Amendments to the
law enacted during 1969 expanded and further defined the duties
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\ VTT/T4S
HAR80K
PACIFIC
:'. 'Southwestf Air ::
: Pollution IControl :;
:' Columbia-Wi 1 lamett
:-'.Air Pollution
Authority
?RS^?M/
. lamette
::;:Valley Air
^Pollution
Authority
JZSCHU7ES T
Lane Regional Air .:
Pollution Authority ::::
Figure 8 . Air Pollution Control
Authorities.
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24
of the Board. It was given the authority to adopt air quality
objectives (levels of contaminants in the air below which
undesirable effects will not occur), air quality standards (levels
of air pollution which shall not be exceeded), and emission
standards (limitations on the release of contaminants into the
ambient air). The State Board was assigned responsibility for
enforcement of its standards except in areas where local programs
are enforcing standards which are at least as stringent as those
of the State. However, the State was directed to exercise statewide
control over emissions from certain categories of pollution
sources if such control was determined to be in the public interest
and for the protection of the welfare of the citizens.
One primary function of the State program has been to foster
the development of county and multl-county programs throughout
the State. To serve this end, the State program may assist the
various local programs with financial aid and technical assistance.
One such program is the Southwest Air Pollution Control Authority
which was formed in April, 1968, and has Jurisdiction in the five
counties of Clark, Cowlitz, Lewis, Skamania, and Wahkiakum.
Administration of the Authority is handled by an eleven member
Board of Directors. The Authority has the responsibility of
controlling the sources within its five-county jurisdiction.
Coordination of activities of the control agencies in the Pacific
Northwest is achieved through the Washington State Control
Officers Association. The objective is to coordinate air monitoring,
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25
data reporting, overall planning and control activities.
The Oregon-Washington Air Quality Committee was established
by the Governors of the two States. The purpose of the Committee
is to aid in coordinating control activities in the interstate
area. The Committee consists of representatives from the Washington
State Air Pollution Control Board staff and the Oregon State
Sanitary Authority staff, with staff members of the Columbia-
Willamette Air Pollution Authority and the Southwest Air Pollution
Control Authority as advisory participants. The Committee meets
monthly and works on inventories, standards, data exchange, and
sampling methods.
REGIONAL PLANNING IN THE STUDY AREA
Planning in the Study Area is handled by eight planning
agencies, five of which are multi-county in scope. Figure 9
shows the boundaries of the regional planning arrangements.
The Columbia Region Association of Governments, CRAG,
consists of the four counties of Multnomah, Clackamas, Washington,
and Clark. Membership is open to all cities within these counties,
and over 20 cities have joined. CRAG serves as the regional
review agency for Federal financial grant application. Its
activities Include comprehensive area-wide plans for sewage,
water, transportation, recreation facilities, land-use, and
other services.
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S
SCALE:
VILfS
T
L.
JX5 HAKBQK
PACIFIC
rHUKSTON \ P'LKCE
~\
Lewis Regional Planning Commissions
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*£M3\
SLATSOP
, COLUMBIA •
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mmm Governments mmmmm
JETFE&SON
• ••••*•••••;••••••••••»•••# •• »O • • • • • • » • • • • • • • * • ••*••"* g— - -^^
^mm^m^m&^mmmm Yc«°™
m&vroummw^^ ^sc^^s T
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I Central Lane Planning Council
U4sa
xr^/v/>?7"/y
^x-o?
^<*?5
OOUQUIS
Portland Metropolitan
^7 Study QMHiaaton CMSC}
f91"?***??*^1
Figure 9.
Regional Planning agencies
in the Portland Study Area.
Counties in both NSC and CRAG
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27
The Portland Metropolitan Study Commission was created
by the Oregon State Legislature in 1963 and serves the counties
of Clackamas, Columbia, Multnomah, and Washington. Its main
functions have been the following: "to determine the boundaries
within which it is desirable that one or more metropolitan
services be provided" and to prepare a "comprehensive plan for the
furnishing of such metropolitan services as it deems desirable
in the metropolitan area". (ORS 199.230) Originally it was
planned that the Commission would expire in June. 1969, but the
life of the Commission has been extended to June,1971.
The Mid-Willamette Valley Council of Governments covers
Marion, Polk, and Yamhill Counties. Besides the counties, the
membership also includes the State of Oregon, six cities, a school
district, and a fire district. The Council was formed in 1967
by the merger of the Mid-Valley Planning Council and the Inter-
governmental Cooperation Council. Areas of interest and activities
include land-zoning, transportation, urban renewal, comprehensive
plans for sewer and water facilities, and population studies.
The Linn-Bent on Association of Governments (LBAG) has
representatives from Linn and Benton Counties and from four
cities in these counties. The LBAG was organized in June, 1967,
and is now the official review agency for Federal funds in the
two-county region. The Corvallis-Benton County Planning Agency
and the Linn County Planning Agency have contributed staff to
LBAG, which has Just recently taken on its first full-time staff
member. Among its activities are comprehensive health and law
-------
28
enforcement planning. There is a possibility that Lincoln County
will join LBAG In the next few months.
The Central Lane Planning Council was originally established
in 1945 as the Central Lane County Planning Commission. The
Commission was changed to the Council in 1961, and in 1964, it
required that voting members be elected officials. The Council
has initiated or supported land-use, transportation, and long
range development plans for the urbanized portions of Lane County.
It has also worked in such areas as employment forecasts, zoning,
park development, and urban renewal.
In October, 1968, Wahkiakum County joined the previously
established Cowlitz Regional Planning Commission to form the
Cowlitz-Wahkiakum Regional Planning Commission. The Commission
is now the planning agency for all cities, towns, and counties
in the Cowlitz-Wahkiakum Region. The Commission has conducted
studies of population, urban area economics, land-use, subdivision
and zoning, and building codes. Other areas of concern are
urban area sewer and water supply, location of future schools,
housing, transportation, industrial land sites, and solid-waste
disposal.
Lewis County has two commissions—the Lewis County Planning
Commission and the Lewis Regional Planning Commission. The
County Commission was formed in 1962 and is composed of nine
members, three each from each commission district. The prime
function of the County Commission Is to review subdivision
-------
29
plats and to hold work sessions on codes and ordinances for the
County. The Regional Commission was formed in 1965 and has
representatives from the County and, at present, six cities.
The Commission's main purpose is to coordinate and approve planning
in the Region.
The Skamania County Planning Commission was formed in 1967.
To date, it has no full-time staff. The Commission deals with
platting regulations and is presently working on a comprehensive
land-use plan for the county.
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30
EVALUATION OF ENGINEERING FACTORS
INTRODUCTION
The engineering evaluation for the Portland Study Area was based
on a study of topography, meteorology, air pollutant emissions,
pollutant diffusion, and air quality. The emission inventory
indicated the location of point and area sources and quantity
of pollutants emitted from these sources. Emission densities
were calculated from the emission quantities and grid zone areas.
A qualitative evaluation of air quality was made based on air flow
and thermal stability.
EMISSIONS INVENTORY
The National Air Pollution Control Administration conducted
an inventory of air pollutant emissions for the Portland Study
a
Area. Five pollutants were inventoried--total particulates,
sulfur oxides, carbon monoxide, nitrogen oxides, and hydrocarbons.
Only three of these--total particulates, SO^, and CO--are considered
in this report, since these pollutants provide an indication of
the general air pollution problem. Particulate emission levels
indicate primarily the location and extent of pollution emanating
from industrial, power, incineration, and heating sources.
Levels of sulfur oxides illustrate the Impact of fuel burning
activities at stationary sources. Levels of carbon monoxide
show the impact of gasoline-powered motor vehicles on the regional
air pollution pattern. A summary of the emissions inventory
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31
by jurisdiction and source category is given in Table II.
Figure 10 breaks down the total emissions into percent
contribution by the various source categories. Process losses
contribute 48% of all sulfur oxide emissions. Most of these
emissions come from the kraft pulping, aluminum, and wood products
industries. Fuel combustion accounts for 39%, transportation
for 11%, and refuse disposal for 2% of sulfur oxide emissions.
Process losses also contribute most of the particulate emissions
(65%). Besides the kraft pulping, aluminum, and wood products
industries, high process emissions are found in the cement,
grain, and foundary industries. Emissions from Wigwam-type
burners are also included under process losses. Slash and field
burning account for 15% and refuse disposal for 11% of particulate
emissions. The remaining 9% eminate from transportation and fuel
combustion sources. Transportation sources account for the
majority of carbon monoxide emissions in the Study Area (69%)
since the motor vehicle is the main contributor. Wigwam-type
burners contribute most of the 14% shown under process losses, and
slash and field burning contribute 11% of the carbon monoxide
emission load.
Figure 11 shows the percent contribution to the total emissions
of particulates, SQ^, and CO by the counties making up the four
regional air pollution control agencies (see page34).
Eighty-six percent of the Study Area's sulfur oxide emissions
are from the nine counties in the Columbia-Willamette and the
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32
Sunary of Brtialoni from the Portland Study Area
by Source Category (Ton* per year)
County
Clark
Cowllta
Lavls
SksHanla
Colu
9 MultnoMh
-i Beaton
« Marlon
linn
Polk
Washington
Clark
Cowllti
Lewie
Total*
Hahklakum
• Columbia
• Clackanaa
Hultnomah
Banton
Marlon
Lino
Folk
Yeafalll
**
1
Total Fuel
Coabuetlon
152
858
816
71
52
857
485
284
342
834
417
91
273
1,062
591
11
Washington
19,183
245
98
89
7
6
139
177
1,444
49
152
116
25
54
199
106
Industrial
Process Loaaaa
10,475
8,604
7
7
1
408
299
2,065
14
803
56
7
804
431
0
23,981
7,104
12,132
437
255
51
3,432
11,563
15,396
3,659
599
8,770
1,789
2.120
9,839
45
Transportation
277
170
139
13
8
64
324
2,390
107
399
314
101
117
539
274
5,236
538
314
257
25
15
119
548
2,586
209
740
648
176
202
1,115
481
Refute
Disposal
130
25
21
3
1
14
130
300
27
99
23
19
23
204
118
1.137
1,529
360
241
44
21
176
1,529
2,399
337
829
243
234
287
2,949
1,485
Mlseallanaous
Field and Slash
Burning
14
1,328
134
1,414
2,042
6,546
1,093
706
4,155
95
Total
12.034
9.637
983
94
62
1.343
1,238
16,039
490
2,135
810
218
1.217
2.236
983
48,539
9,416
12.904
1,024
331
93
3,880
15,145
21,959
5,668
4.362
16.323
3,317
3,369
18,257
2.212
Contribution
By County
24
19
2
3
3
32
1
4
2
2
5
2
8
11
3
13
18
5
4
14
3
3
15
2
Totali
Washington
2.906
20
12
11
1
0
11
19
188
7
24
11
5
7
27
16
77,191
482
11,387
9.489
9,489
1,897
285
4,990
556
22,001
1,172
33.639
11,281
2,399
28,762
1,630
7,973
47,253
30,581
25,069
2,433
1,524
11.739
68,110
180,156
17,446
72,160
43,531
20.466
23,810
93,014
62,239
12,663
7,899
1,894
1.239
234
156
917
7,899
12,899
1,749
4,089
1,241
1,216
1.493
15.534
7,720
17.527
95
8.386
860
8,998
12,898
41,442
6,901
4.490
26,578
729
118,260
55,654
43.874
35,808
12,157
3,377
13,047
119.419
194,659
50,201
90.343
119,864
39,869
32,199
163,915
72,334
5
4
3
1
1
11
19
5
9
11
4
3
16
7
Totals
359
139,459
699,531
66,179
111,377
1,046,920
-------
Sulfur Oxides
TOTAL: 49,539 tons/year
Carbon Monoxide
TOTAL- 1,046,920 tons/year
Process Losses (includes
wigwam-type burners)
Fuel Combustion
Transportation
Refuse Disposal
Misc. (includes field and
slash burning)
33
Particulates
TOTAL: 118,260 tons/year
Figure 10. Emissions of
Sulfur Oxides, Particulates
and Carbon Monoxide in the
Study Area by various
Source Categories.
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34
Southwest Air Pollution
Control Authority Lewis,
Wahikakum, Cowlitz, Clark,
and Skamania Counties)
Columbia-Willamette Air
(Columbia,
tun, and
"olumbia-Willamet
pollution Author!
lultnomah, Wasliin
Clackaraas Countie
A Mid-Willamette Valley Air
lution Autnon VFOIK,
Bentpn, Yamnill, Marion,
A
and Linn Counties)
Lane Regional Air Pollution
Authority (Lane County)
Sulfur Oxides
TOTAL" 49,539 tons/year
Particulates
TOTAL: 118,260 tons/year
Figure 11. Percent Contribution
to Emissions of Particulates,
Sulfur Oxides, and Carbon
Monoxide by the Air Pollution
Control Authority Jurisdictions.
(For a breakdown by county,
see Table 11.)
Carbon Monoxide
TOTAL: 1,046,920 tons/year
-------
35
Southwestern Washington Regions. The participate loading is more
evenly distributed by region with the Columbia-Willamette (4 counties)
contributing 36%, the Mid-Willamette Valley (5 counties), 28%,
Southwestern Washington (5 counties), 20%, and Lane County, 16%.
The ten Oregon Counties contribute 86% of the carbon monoxide
emissions, since most of the population (and therefore motor vehicles)
are located there, and most of the slash and field burning is found there,
Grid coordinates based on the Universal Transverse Mercator
System were used in the inventory to aid in determining the location
of sources and emissions. As shown in Figure 12, the Study Area
was divided into 71 grids of three different sizes--100, 400, and
1600 square kilometers. The estimated annual emissions of each of
the three contaminants by grid zone were converted to daily emissions
for average, maximum, and minimum space-heating days. Average
emission densities were determined by relating the total quantity
of pollutants emitted in each of the grid zones to the land area
of each zone. The estimated emission densities by grid zone for
average space-heating days are shown in Figures 13, 14, and 15.
Highest emission densities of sulfur oxides are found in the
Portland, Longview, Salem, and Eugene areas. The same is true of
particulates. Particulates and carbon monoxide emissions appear to be
more widespread than sulfur oxides, especially in the Oregon section
of the Suudy Area. Major point sources in the Study Area are shown
in Figure 16. The sources shown emit more than one ton per day of
sulfur oxides or particulates,or more than 10 tons per day of carbon
monoxide.
-------
36
Figure 12. Emissions
Inventory Grid System.
-------
37
»
LEWIS
I WAH
/
WAHKIAKUM
\
Figure 11. Mean Daily Density '
of Sulfur Oxides Emissions
in the Portland Stduy Area
tons/mi, /day
>0.5
0.1--0.5
0.05--0.1
0.01--0.05
<0.01
C 0 rf L I T Z
T
S K A M A N I Ai
MULTNOHAH »
L
LINN
JB E N T 0 N C
V /
A
L /
LANE
\
*
\
I
(
^
..o
<
I
-- /
/
I
\
\
~ - ^
1
;
r
/
/
i
r
i
,, -J
-------
38
LEWIS
JWAHK1AKUM
Figure 14. Mean Daily Density\
of Particulate Emissions *>^
in the Portland Study Area •
I
TONS/Mi. /DAY
|>0.5
0.1---0.5
0.05--0.1
0.01--0.05
SKA MANIA
-------
39
LEWIS
WAHKI
\;
Figure 15. Mean Daily Density V
of Carbon Monoxide Emissions
in the Portland Study Area.
Tons/Day/Mi.'
• 3
2---3
1---2
M
IS K A M A N I A f
I
*
•
-------
40
r
•
IWAHKIAKUM
Figure 16. Location of Major
Point Sources in the Portland
Study Area ( Each source i
shown emits more than 1 ton/ |
day of sulfur oxides or j
particulates, or more than
10 tons/day of carbon monoxidei
Type of Source
• -Industry
• —Dump
^-Airport
LEWIS
COWLITZ JSKA
I
\
MANIA
)
V
ARK
r
,' WASHINGTON
^
MULTNOMAH
;f
\
A C K A M A
MARION
LINN
\
LANE
I
-------
41
DIFFUSION AND AIR QUALITY
Introduction
q
A meteorological diffusion model is generally employed
in an engineering evaluation to determine the extent of the air
pollution problem. Source locations, an emission inventory and
meteorological data, particularly wind direction frequencies
and thermal stability characteristics of the atmosphere, are the
major input factors of the model. The model gives fairly good
results in areas where the terrain is flat and there are no major
topographic features. However, the high mountains to the east
and west of Portland and the valleys of the Columbia and Willamette
Rivers have such marked effects on the flow patterns and stability
of the atmosphere that the model cannot be satisfactorily employed
in the Portland area. Discussions of air flow patterns and thermal
stability and a qualitative evaluation of the extent of the
pollution problem are substituted for estimates from the diffusion
model. (The location of major sources and emission inventory
are discussed in the preceding section.)
Topography and Air Flow
Portland is about 65 miles east of the Pacific coast at
the confluence of the Willamette and Columbia Rivers. The city
is midway between the north-south oriented coast range on the
west and the higher and parallel Cascade range on the east,
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42
each about 30 miles distant. The Columbia River flows through
both of these ranges within narrow gorges. Figure 17 shows the
area and displays elevations above 2000 feet.
In evaluating the air flow in the Columbia River Valley,
: |
data from the following locations are considered: a) the Dalles
at the eastern end of the gorge in the Cascades; b) Portland,
where the downriver flow changes from westward to northward;
c) Kelso, where the direction changes from northward to westward;
and d) Astoria, at the mouth of the river. The flow in the broad
Willamette Valley is evaluated through observations from the
following locations: a) Eugene, at the south end of the Valley;
b) Salem; c) Portland, and d) Kelso. The Cowlitz Valley to the
north of Kelso is a straight extension of the valley in which
the Columbia River flows northward, so observations from Toledo,
Washington, near the point where the Cowlitz River starts its
southerly flow toward the Columbia River, are included. Data
for each mid-season month are presented.
The prevailing surface flow in January, as shown in Figure
18, indicates that there is a general movement from east to west in
the Columbia River Valley and from south to north in the Willamette-
Cowlitz Valley areas. This northward flow is so frequent and
persistent that a backward trajectory technique demonstrates that
many air parcels eventually found over Portland and Kelso were
at one time over Eugene.
In April, the prevailing surface flow is more complicated
than that of January (Figure 19). The flow is upvalley in the
-------
.—•"—*— 1
- •
Figure 17. Portland Study Area Topography
(Shaded areas show elevations over 2000 feet)
-------
1
ir- -- • LEW/S |S
tunA i -i n* 1'• • —- — • A*
; 2111
v» S'S®SSS¥ •.,-.;.-: •;-:t:X:-:-:; :x-x x :•': • - :-:-
SN^.>* . i •'•••":• !§!• -::-:-!-;::';:- • ' ^ •'
;> .^,.;-0^]x-- ' :,:;.:••'
r—J ~~ /
t, SthiTOU «•
J—•»-*•.*— - — . _t
•>:-:Vx;::::x:x:y:-:-::x:x-::x:Xv'<::->::':x-:':^::>>>>;'.'::x-x- -t_
x-x':':-:-x:x::^:-::x::-::x:x'x:::::.:::::': '••:::':::':::'-::: • ::>x:.:::x::-:-'
i
L
,-
30UGUIS
>v
Figur« 18. PcwvAiliog Fiona. January
of Flikft
-------
•'•'.•I-','.': •"• '•'•X-X'I*X»!>X'X*X*XvX'.i^!*!'!'? * !*' ?.>'•-
VJ
k
LIKlCOLfJ !"'.. \
r»J ^
»'
k 0E.UTOU i
I,
u
j.v
- - -^— -.y-i;ivi;;<«'»»). • •' ;! _.;; •••";" . :•' ''-'vX'X'X
Figure 19. PMvailing Flows, April
Arrows Indicate Direction of Flow
Primary
Secondary
-------
46
Columbia River Valley. The most frequent flow in the Cowlitz
Valley is upvalley but downvalley flows are also frequent. In
the Willamette Valley the movement for the most part is downvalley,
and somewhere between Portland and Salem, flows from opposing
directions meet.
The prevailing surface flow in July is practically the
reverse of that of January (Figure 20). Air movement is upvalley
in the Columbia River Valley and from north to south in the Cowl it z-
Willamette Valley area.
In October (Figure 21) the prevailing surface flow is similar
to that of April. The most frequent flow in the Willamette-
Cowlitz Valley is northward. In the Cowlitz Valley downvalley
flows are a little less frequent than the upvalley flows. The
air movement in the Columbia River Valley, except at the Dalles,
is mostly downvalley. At all stations from Portland to the
Coast there are important secondary flows, and these are in a
general upvalley direction.
Since valley locations often show two opposing wind flows
on a diurnal basis, data from Portland were examined to see if
such diurnal variation could account for the observed dual
flows at some stations. Prevailing winds for midnight to 5:00
A.M. were compared with those for noon to 5:00 P.M. The results
are shown in Table III.
-------
•y WKtXJK. "-V
k
SCALE:
V/i^S
•:": ^ - ^iiii*!*^
J ii i::' • :' : -i:: ^
;•:•'•: ::;: >::: iixVr'xox'x^xv • -''•
A: ..::. •.
tf
V
r
TILLAMOOK'. }•
^
.
L1UCOLU
J
r
^ S£.MTOU '<
L
u
p^^fe^^p^ T
r>!>^«NV»v»'^5^ ; _ -. X-'-XVf f-'-lM I-.-
I
MA/f
f-:t
OOUGi-AS
Figure 20. Prevailing Fiona, July
Arrows Indicate Direction of Flow
Primary Secondary
-------
48
(jKAYS HAKBOK
PACIFIC ]
¥
dY >//T/t: :.;•::: Alv; ' --XA
, ..
'
-T v
-T r-vx
C 0LNTOU
J—•^•-s— - .
.-x::': ivivi'wiwiv :: : :. : : : : : :: : V
.
^^^^:$:g5|^|x||^||;:::iS:::: • :.j^. i. >;; | I
....:x:x:::::x:x:x;;:>::^:;x;x;:x:;:;:::.,:;:::::: ^::: •*!:•;.:
u
i
f
'
. "•
j:|;;
Figure 21. Prevailing Flows, October
Arrow* Xndicat* Dtrtction of lion
Prlnan
-------
49
Table III. Prevailing Winds*, Portland, Oregon
Directions and Percent Frequency
(Based on data supplied by C. Hopper)
Month/Time 0000-0500 1200-0700
January-Most Frequent ESE 48 ESE 45
Next Most Frequent SSW 24 SSW 25
Calms (%) 9 5
April- Most Frequent ESE 22 NW 39
Next Most Frequent NW 22 SW 17
Calms (%) 22 15
July- Most Frequent NW 52 NW 75
Next Most Frequent SSE 8 SSW 6
Calms (%) 17 1
Oct.- Most Frequent SE 30 NW 32
Next Most Frequent SSW 20 SE 25
Calms (%) 23 5
* 3 sectors wide centered on indicated sector, based on 16 point
compass.
In January there is little change from morning to afternoon
indicating that there is practically no diurnal variation in
winter. There is a considerable increase in NW winds and decrease
in SE winds from morning to afternoon in April, indicating that
there is a marked diurnal shifting of the wind. This is assumed
to indicate that the stations showing dual, almost opposing,
flows in Figure 19 (April prevailing flow data) also experience
this daily back and forth movement of air in their area; the flows
are primarily downvalley in the morning and upvalley in the
afternoon. In July there is a marked increase in the frequency
of NW winds from morning to afternoon. This indicates that at
times during the night the flow becomes so light that it is
-------
50
undetectable by the instruments, or variable; but there is no
marked reversal of flow from night to day. The air movement during
July is thus fairly persistent in one direction. In October there
is only a slight decrease in the frequency of SE winds from morning
to afternoon. As in April, the change in the most frequent flow
is from downvalley in the morning to upvalley in the afternoon.
Since movement of air within the first few thousand feet of
the surface is important in air pollution evaluations, a summary
of these data for Portland is shown in Table IV.
Table IV. Prevailing Winds, and Winds Aloft, Portland, Oregon
(Winds Aloft Data from Airway Meteorological Atlas
for the United States U2~] ) .
Height / Period Dec-Jan-Feb Mar-Apr-May June-July-Aug Sept-Oct-Nov
m (feet)
Surface ESEZ NW2 NWZ SEZ
500 (1640) E NNW NNW NNW*
1000 (3280) SSW SW NNW SW
2000 (6560) SSW SW WSW SW
3000 (9840) SW WSW SW WNW
z - midseason month data
* - E winds are almost as frequent
It is obvious that most of the year there is one wind regime in
*
the layer from the surface to some height between 1640 and 3280
feet and that there is another wind regime above. This phenomenon
appears to be related to the stability characteristics of the
atmosphere (discussed in the next section). A study12 now in
progress is obtaining additional data. On December 5, 1969,
-------
51
the investigators found that there were weak winds from the surface
to 1000 feet, a strong easterly gorge wind between 1000 and 3000
feet and W-SW winds above 3000 feet. The easterly gorge wind is
practically restricted to the winter. When it occurs it changes
a complicated two-layer flow into a very complicated three-layer
flow. These drastic changes in direction with height, complicates
the problem of trying to make a model of the atmosphere. Diffusion
evaluation would be most difficult to make if these changes in
direction with height had to be taken into account. However,
as explained in the following section, vertical mixing is very
frequently restricted to the lower 2000 to 3000 feet and movement
in the upper layer does not have to be considered.
Thermal Stability
The stability characteristics of the atmosphere give an
indication of the depth through which vertical mixing takes
place. When the temperature increases with height, an inversion
of temperature is said to exist. When the inversion layer is
based at the surface and sufficiently deep, effluents generally
tend to spread out horizontally in a flat layer, or initially
rise for a time (until they lose their buoyancy) and then spread
out. Inversions are described as being thermally stable. If
the inversion layer is aloft, the base of it acts as a lid and
inhibits vertical mixing up into the inversion. An opposite
effect is caused by a superadiabatic layer in which the adiabatic
-------
52
lapse rate (a decrease In temperature with height at the rate of
5.4°F per 1000 feet) is exceeded. In a superadiabatlc layer,
conditions are unstable, vertical motion is constant and vertical
mixing is considerable. In a neutrally stable layer, i.e., one
with an adiabatic lapse rate, parcels tend to remain in place or
if displaced up or down by an outside force, will move only as
long as that force is applied. A layer which shows no change of
temperature with height is called isothermal, and vertical air
movement in such a layer is similar to that in an inversion. Layers
showing a decrease in temperature with height but a decrease less
than adiabatic are also stable and exhibit little vertical mixing.
Over undeveloped, rural areas radiation or surface based
inversions readily form around sunset when the skies are clear
and the winds light. In built-up areas, the frequency of surface
based inversions is not as great, and often an inversion base
is displaced a few hundred feet from the surface. A seasonal
summary of the percent frequency of inversions at or within 500
feet of the surface in the Portland area is shown in Table V.
Table V. Percent Frequency of Inversion And/Or Isothermal
Conditions, Baaed on Below 500 Feet Above Station
_________ Elevation - Portland-Salem Area
Time P.S.T.
Season
Winter
Spring
Summer
Fall
From: C. R. Hosier's Low-Level Inversion Frequency in the Contiguous
United States (8).
4 AM
51
63
74
71
7 AM
41
20
3
43
4 PM
8
1
0
2
7 PM
36
19
14
49
-------
53
It is seen that low-level inversions are present over half of
the nights in each season. Another investigator using only the
Salem data fround that stable layers with bases at the ground occurred
877. of the time at 4:00 A.M.1* In the afternoon, as shown by the
4:00 P.M. data in Table V, the inversions are eliminated almost
everyday. It should be remembered that these nocturnal inversions
are generally present for several hours or more each time they
occur, whereas the maximum mixing depth, which is discussed in
a following paragraph, is a phenomenon lasting an hour or less in
time.
The data on surface based, or low-level inversion, indicate
the frequency of the stable extreme in vertical mixing. This
extreme is generally eliminated shortly after sunrise; at times
in winter it may be noon or 1:00 P.M. before the inversion Is
eliminated. The other extreme occurs when the sun heats the ground
and ground-based adiabatic or superadiabatic layer is formed and
gets progressively deeper until a maximum depth is reached during
the afternoon. Holzworth^-5 used a standard technique for computing
mean miHHnyim mixing depths for Portland and his results are shown
in Table VI.
Table VI. Computed Afternoon Mean Mixing Depths - Holzworth (6)
•
Season Height in Feet
Winter 1970
Spring 4920
Summer 5250
Autumn 3610
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Since It Is well documented1** that subsidence inversions or inversions
aloft occur over the Willamette Valley and sections of the Columbia
River Valleys, these computed mixing depths have to be compared
to observations of inversion base heights. Cramer, through
temperature profile observations obtained from an aircraft, has
found that the inversion generally has bases between 2000 and 3000
feet above the surface. He reported18 that these observations
are further confirmed by his observations of air pollution
plumes in the area; these plumes generally have tops of 2000
to 3000 feet above the surface. These temperature and air pollution
plume observations are more in agreement with the winds aloft
(TableIV) than the computed mixing depths; the winds aloft
indicate that the winds associated with the subsidence, SW, are
at lower levels than the computed mixing depths. It thus appears
that a base about 2000 to 3000 feet above the surface most
frequently limits the vertical mixing on most days of the year,
and that during the summer vertical mixing is probably a little
greater than 3000 feet.
The air flow patterns indicate that air parcels are readily
transported long distances in a north or south direction in the
Willamette Valley. In the Columbia River Valley, east and west
flows predominate to the east of Portland and west of Kelso but
the net transport in one direction is not as great as that in
the Willamette Valley. The poor vertical mixing which occurs
on a majority of nights combined with vertical mixing restricted
to 3000 feet or less on most days aggravates any pollution
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55
problem because these phenomena allow for little dilution in the
vertical.
Relating the potential diffusion discussed above to the sources
of the area, the following are found. Pollution from a number
of major point sources in the Kelso-Longview area^ could be expected
to readily reach places in Cowlitz, Columbia, Clark, Washington,
and Multnomah Counties. Pollution from the numerous major sources
19
in the Portland-Vancouver-Camas area would affect the air quality
of Multnomah, Skamania, Clark, Cowlitz, Columbia, Washington,
Clackamas, Yamhill and Marion Counties and possibly Hood River
County. Pollution from the area-wide agriculture burning during
the summer of approximately 300,000 acres in the area south of
Salem generally contaminates the whole southern end of the
Willamette Valley, including Marion, Polk, Benton, Linn and
Lane Counties. Evidence of the magnitude of this problem was
20
given on August 12, 1969. The situation became so bad in
Eugene that a temporary ban was put on agricultural burning
in the area. Paper plants ringing Corvallis are also major
sources of pollution in the southern end of the Willamette
Valley and cross-county air flow causes them to offend neighbors
in other counties.
Thus, it appears that there is mutual responsibility for
air quality in the Willamette Valley by all counties in the
Willamette Valley and Columbia, Clark, Cowlitz and Skamania County.
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THE PROPOSED REGION
Subject to the scheduled consultation, the Secretary,
Department of Health, Education, and Welfare, proposes to designate
an air quality control region for the Portland area, consisting
of the following jurisdictions:
In the State of Oregon: In the State of Washington:
Benton County Marion County Clark County
Clackamas County Multnomah County Cowlitz County
Columbia County Polk County
Lane County Washington County
Linn County Yamhill County
As so proposed, the Portland Interstate Air Quality Control
Region would consist of the territorial area encompassed by the
outermost boundaries of the above jurisdictions and the territorial
area of all municipalities located therein and as defined in Section
302(f) of the Clean Air Act, 42 U.S.C. 1857th(f). Figure 22
shows the boundaries of the proposed Region while Figure 23
indicates the geographic relationship of the Region to the
surrounding area.
DISCUSSION OF PROPOSAL
To be successful, an air quality control region should
meet three basic conditions. First, its boundaries should
encompass most of the pollution sources as well as most of the
people and property affected by those sources. Second, the
boundaries should encompass those locations where Industrial
and residential development will create significant air pollution
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Figure 22. Proposed Boundaries of the Portland Interstate Air
Quality Control Region (Cfre^dn-Washington)
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58
Puget Sound Air Quality
Control Region
Spokane--Coeur d'
Alene
Clarkston
PulIman
WASHINGTON
Lewiston-
Moscow
Proposed Portland Interstate
Air Quality Control Region
(Oregon-Wash ington)
Boise City
CALIFORNIA
\ M\ ^San Francisco Bay Area
Air Quality Control Region
Figure 23. Relationship of Proposed
Portland Interstate Air Quality
Control Region to Surrounding
Areas.
-Announced Areas for Future Air Quality
Control Region Designation
S V
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59
problems in the future. Third, the boundaries should be chosen
in a way which is compatible with and even fosters unified and
cooperative governmental administration of the air resource through-
out the region. The "Evaluation of Engineering Factors" (discussion
beginning with page 30) discussed the first of these conditions,
and the "Evaluation of Urban Factors" (page ij), the second and
third. The determination of regional boundaries requires that
both urban and engineering factors be considered. The' boundaries
chosen should create a cohesive combination of Jurisdictions suitable
for region-wide administration of an air resource management program.
The rapid-survey emissions inventory gave estimates of emission
quantities and emission densities, and the location of point
sources In the fifteen-county Study Area. Highest emission densities
of sulfur oxides, particulates, and carbon monoxide are found
in or near the cities of Kelso-Longview, Portland-Vancouver, Salem,
and Eugene. Carbon monoxide and particulate densities, however,
are fairly evenly spread throughout the Oregon portion of the
Study Area. Most of the major point sources are located in
Multnomah, Cowlitz, Linn, and Lane Counties.
The analysis of diffusion in the Study Area indicates that
all counties in the Study Area, with the exception of Lewis and
Wahkiakum, could be readily expected to be receptors of pollution
from sources in the Kelso-Longview area, the Portland-Vancouver-
Camas area, or the area south of Salem where agricultural burning
takes place.
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The proposed twelve-county Region has a population of over
1,600,000 people which represents approximately 97% of the people
in the Study Area. There are three main centers of population
in the area: Portland-Vancouver (Clark, Washington, Clackamas,
and Multnomah Counties), Salem (Marion County), and Eugene (Lane
County). The Oregon portion of the proposed Region includes about
70% of the total population of the State, and the Washington
portion represents over 5% of the population of Washington.
The proposed Region allows for both population and industrial
growth in the future. Major population growth is expected to
occur in the metropolitan areas of Fort land-Vancouver, Salem,
and Eugene (Clark, Multnomah, Washington, Clackamas, Marion,
and Lane Counties^ The remaining six counties are also projected
to have shown population increases from 1960-1980 ranging from
34% in Cowlitz County to 86% in Folk County.
The third objective, that existing regional jurisdictions
be considered, is most difficult to meet. The Oregon portion
of the proposed Region includes three regional air pollution
control authorities, and all ten counties are included in the
authorities (see Figure 8). There are five regional planning
groups in the Oregon portion, and none of these agencies has
jurisdiction outside the proposed Region boundaries. In
Washington, only two of the five study area counties are proposed
for inclusion in the Region—Cowlitz and Clark. Most of the
population and industry are located in these counties. Inclusion
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of the remaining counties In the Southwest Air Pollution Control
Authority seems unnecessary due to their relatively low population
densities and growth projections and the lack of large pollution
sources. Cowlitz County has added Wahkiakum County to its Regional
Planning Commission. It is the policy of the Planning Commission,
however, to cooperate with all State, Federal, and local air
21
pollution authority commissions, so there should be no conflict
in having only Cowlitz County in the Region.
The final decision on the inclusion or exclusion of Lewis,
Wahkiakum and Skamania Counties, however, will be made only after
careful review of comments submitted to the Consultation record
by State and local officials. Should they be excluded from the
Region at the present time, they should nevertheless be observed
carefully and added at a later date if it appears that the air
pollution menace is growing due to increases in population and
industry.
The boundaries proposed in this report for the Portland
Interstate Air Quality Control Region will serve as a starting
point for discussion with State and local officials at the scheduled
Consultation.
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REFERENCES
1. Commercial Atlas and Marketing Guide. 100th Edition, Rand-
McNally and Company, 1969.
i
2. "Population Growth in the Mid-Willamette Valley" Staff Papers:
Population, Annual Series, Issue Mo. 4, January, 1970, Mid-
Willamette Valley Council of Governments.
3. "Population - Economics - Land Use", Cowlitz-Wahkiakum Regional
Planning Commission, Cowlitz County Courthouse, Kelso, Washington,
October, 1968.
4. "Population and Employment, Technical Appendices", excerpts
from: Eugene-Springfield Metropolitan Area Preliminary 1990
General Plan, Central Lane Planning Council, 1969.
5. "Employment and Population Projections to Year 2000", Portland-
Vancouver SMSA, Columbia Region Association of Governments,
Portland, Oregon, August, 1968.
6. "Population Forecasts, State of Washington, 1965 to 1985,"
State of Washington, Department of Commerce and Economic
Development, Olympia, Washington, 1966.
7. "Population Bulletin", Release Number P-9, Oregon State Board
of Census, Portland State College, Portland, Oregon, October,
1963.
8. "Rapid Survey Technique for Estimating Community Air Pollution
Emissions," PHS Publication No. 999-AP-29, Environmental
Health Series, USDREW, NAPCA, Cincinnati, Ohio, October, 1966.
9. Martin, D. 0. and Tlkvart, J. A. - A General Atmospheric
Diffusion Model for Estimating the Effects on Air Quality of
One or More Sources, Paper No. 68-148, 61st Annual Meeting,
APCA, St. Paul, Minnesota, June 1968.
10. Hopper, C. - (Personal Communication) Letter of January 14,
1970, Including wind rose data for each three-hour period
of each midseason month.
11. U. S. Weather Bureau - Airway Meteorological Atlas for the
United States. W.B. No. 1314, U. S. Department of Commerce,
New Orleans, La., 1941.
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12. Olsson, L. E. - Proposed Work Plan—Investigation of Natural
Ventilation of the Portland Area and the Willamette Valley.
Department of Atmospheric Sciences, School of Science and Air
Resources Center, Oregon State University, Corvallls, Oregon,
January 1970.
13. Hosier, C. R. - Low-Level Inversion Frequency in the Contiguous
United States. Monthly Weather Review 89 (9): 319-339,
(September) 1961.
14. Oregon State Board of Health - Air Pollution in the Portland
Metropolitan Area, September, 1963.
15. Holzworth, 6. C. - (Personal Communication) Letter on computed
mixing depths over the United States, April 15, 1969.
16. Cramer, 0. P. and R. E. Lynott - Cross-Section Analysis in the
Study of Windflow over Mountainous Terrain. Bulletin American
Meteorological Society, 42 (10), 693-702, (October) 1961.
17. Cramer, 0. P. - Implications of Atmospheric Potential Temperature
Structure on the Distribution of Aerosols in Western Oregon.
Paper presented at Pacific Northwest International Section
Meeting, Air Pollution Control Association, Salem Oregon,
November 9, 1967.
18. Cramer, 0. P. - (Personal Communication) Letter on movement
and depth of polluted layers west of the Cascades, October 18,
1968.
19. Hendrickson, E. R., Kengy, D. M., and R. L. Stockman - Evaluation
of Air Pollution in the State of Washington. Robert A. Taft
Sanitary Engineering Center, Cincinnati, Ohio, 1957, 145 p.
20. Colby, R. - (Newspaper Article) Eugene Becomes 'State of Anarchy1
As Battle on Field Burning Rages. The Sunday Oregonian,
August 17, 1969, p. 34.
21. "Regional Planning Scope and Purpose," Cowlitz-Wahkiakum
Regional Planning Commission.
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