Residential and Commercial/Industrial Development Model (RECID)
Ecosystem Landscape Modeling System
(Revised 5-26-06)
The residential and commercial/industrial development (RECID) model simulates residential and
commercial/industrial development for alternative futures. The model integrates six elements: (1)
alternative futures; (2) historical changes in land cover and transition probabilities; (3) set of
undeveloped parcels; (4) set of developable parcels; (5) total acreage required for development;
and (6) the order and location of parcel development.
1. Alternative futures
A subgroup of the Flathead Landscape Analysis Group (FLAG) developed nine alternative
futures for Flathead County (see table below) by combining three annual growth rates (high,
moderate, and low) for eleven industries between 2004 and 2014 and between 2014 and 2024
(see Appendix A), and three land use policies (unrestrictive, moderately restrictive, and highly
restrictive) (see Appendix B) for the county. Land use policies, which are assumed to be constant
over the entire evaluation period (2004 to 2024), specify the: (1) mix of new home types; (2)
densities for home types; (3) setbacks of new homes and commercial/industrial facilities from
wetlands and water bodies; (4) restrictions on residential and commercial/industrial development
to protect other environmentally sensitive areas (national parks and wildlife refuges); (5)
availability of infrastructure (roads, sewer, power, water, etc.); and (6) percentage of remaining
farmland and forestland in conservation easements.
Nine alternative futures for Flathead County
Economic
growth
rates
Unrestrictive
Land use policy
Moderately
restrictive
2. High growth,
moderately
restrictive policies
Highly restrictive
High
1. High growth,
unrestrictive policies
3. High growth,
highly restrictive
policies
Moderate
4. Moderate growth,
unrestrictive policies
5. Moderate growth,
moderately
restrictive policies
6. Moderate growth,
highly restrictive
policies
Low
7. Low growth,
unrestrictive policies
8. Low growth,
moderately
restrictive policies
9. Low growth,
highly restrictive
policies
2. Historical changes in land cover and transition probabilities
Land covers in populated areas for 1985 and 2002 determined using 30m Landsat TM imagery
(see Appendix C for 2002 land cover), were used to calculate transition probabilities of
conversion of land from agricultural cover to built-up cover, and from forested cover to built-up
cover. Normalized transition probabilities are 0.15 for conversion from forested cover to built-up
cover, and 0.85 for conversion from agricultural cover to built-up cover.1 Transition probabilities
are assumed to remain constant through 2024. These probabilities are used in determining the
conversion of undeveloped land parcels to developed uses.
3. Set of undeveloped parcels
Not all undeveloped land in Flathead County is available for development, even in the absence of
development restrictions imposed by the three land use policies. About 80 percent of the land in
Flathead County is publicly owned and, as such, cannot be developed. These lands include
national and state parks, wildlife refuges, and wilderness areas. Clipping out these public lands
from Flathead County gives the ‘populated areas” map depicted in Appendix C.
The CAMA database and 2004 orthophotography for populated areas of the county developed by
Positive Systems and the Flathead County GIS Office are used to identify the set of undeveloped
parcels that can be developed in the county as of 2004/2005, designated UP. Parcels in this set:
 do not contain residences or commercial/industrial facilities;
 comply with applicable building/zoning restrictions with respect to slope and type
of soil, and geologic and environmental hazards; and
 are not in the designated 100-year floodplain and flood prone areas. Exceptions
are that no more than 25 percent of the area of any new residential lot can be
located within the designated 100-year floodplain in the West Valley area of the
county.
The second and third requirements are spelled out in the Flathead County Subdivision
Regulations, and Flathead County Lake & Lakeshore Regulations.2
1
Normalized transition probabilities are determined by dividing the raw transition probability from forested cover to
built-up cover (0.0049), and the raw transition probability from agricultural cover to built-up cover (0.0275) by the
sum of the raw transition probabilities (0.0324).
2
These regulations are described at:
http://search.netscape.com/ns/boomframe.jsp?query=Flathead+County+Planning+and+Zoning&page=1&offset=0&
result_url=redir%3Fsrc%3Dwebsearch%26requestId%3D5960791f05a36065%26clickedItemRank%3D1%26userQ
uery%3DFlathead%2BCounty%2BPlanning%2Band%2BZoning%26clickedItemURN%3Dhttp%253A%252F%252
Fwww.co.flathead.mt.us%252F%26invocationType%3D%26fromPage%3DNSBoom%26amp%3BampTest%3D1&remove_url=http%3A%2F%2Fwww.co.flathead.mt.us%
2F.
2
4. Set of developable parcels
Since a land use policy restricts where development can occur, it prevents certain undeveloped
parcels from being developed. The set of developable parcels for each land use policy is
determined as follows:
DPq = UP - OR - EPq
(q = unrestricted, moderately restrictive, or highly restrictive),
where:
DPq = the set of developable parcels with land use policy q (represents the supply of land);
UP = the set of undeveloped parcels that can be developed (discussed in section 3);
OR = the set of parcels that cannot be developed due to other restrictions imposed by existing
subdivision, lake, and lakeshore regulations (discussed in section 3); and
EPq = the set of undeveloped parcels eliminated from development by land use policy q.
Other restrictions on parcel development are assumed to be the same for all land use policies and
are based on existing county regulations regarding: (1) lake and lakeshore protection; (2) home
setbacks in the West Valley area; (3) setbacks of motor coach subdivisions from water bodies;
and (4) home densities, setbacks, etc. in the North Fork Valley
These regulations are spelled out in the Flathead County Subdivision Regulations, and Flathead
County Lake & Lakeshore Regulations (see footnote 2).
5. Acreage required for development
The demand for land with each alternative future determines the total acreages required for new
residential and commercial/industrial development in response to economic growth.
Home and residential land requirements. Additional homes required between 2004 and 2014 and
between 2004 and 2024 for an alternative future are calculated using: (1) the increase in
employment between 2004 and 2014 and between 2004 and 2024 determined using IMPLAN;
(2) average number of workers per housing unit in the base year (2004) and the housing vacancy
rate, which determines the number of homes needed by newly employed workers; (3)
unemployment rate; (4) number of non-permanent residents; and (5) average number of nonpermanent residents per housing unit in 2004. [Should probably add an appendix that explains
these calculations in more detail.]
Consider how to calculate the acreages required for additional home types with alternative future
5. Suppose alternative future 5 requires 1,000 additional homes in Flathead County between
2004 and 2014. Based on the percentage of homes in each home type for alternative future 5 (see
Appendix B), an additional 170 high density, 210 urban, 210 suburban, 160 rural, 130 exurban,
and 120 agricultural homes are required. Converting each home type to its average acreage and
3
summing over home types gives the additional acreage that needs to be converted from other
uses to the five home types between 2004 and 2014:
High density: 170/7 = 24.29
Urban homes: 210/5.5 = 38.18
Suburban homes: 210/2 = 105
Rural homes: 160/1 = 160
Exurban homes: 130*7.5 = 975
Agricultural homes: 120*47 = 5,640
The yellow-colored values equal 1,000 times the decimal equivalent of the percentage of
additional homes in each home type (see yellow highlighted values in section A, Appendix B),
the fuchsia-colored values are the average densities (units per acre) for each home type (see
fuchsia-highlighted values in section A, Appendix B), and the gray-colored values are the
acreages required for the five home types. Hence, alternative future 5 requires the conversion of
6,617 acres from undeveloped parcels (undeveloped land zoned residential, agricultural land, and
forested land) to residential uses between 2004 and 2014.
Commercial/industrial land requirements. Additional acreage required for new
commercial/industrial development between 2004 and 2014, and between 2014 and 2024 is
determined by multiplying the increase in employment between 2004 and 2014 or between 2004
and 2024 estimated using IMPLAN by the average commercial and industrial acreage required
per worker (see Appendix D). Suppose these calculations indicate that an additional 500 acres of
land are needed for new commercial/industrial developments between 2004 and 2014 with
moderate economic growth.
6. Order of parcel development
Conversion of the set of developable parcels to residential and commercial/industrial uses
depends on additional acreages required for new residential and commercial/industrial
developments with an alternative future (see section 5 for detail), and the rank order of parcels
for conversion to residential and commercial/industrial uses.
The overall order in which parcels are converted is commercial/industrial first, and residential
second. Subtracting the set of developable parcels converted to commercial/industrial uses from
the total set of developable parcels determines the set of developable parcels available for
conversion to residential uses. Parcel conversion to residential uses is done in the following
order: (1) high density; (2) urban; (3) suburban; (4) exurban; and (5) agricultural. In other words,
the set of developable parcels available for residential uses is converted to high density homes
first, urban homes second, etc. After parcels are converted to a particular home type, those
4
parcels are removed from the set of developable parcels available for residential development
before parcels are converted to the next home type.
The procedure for converting developable parcels is based on development attractiveness scores
(DAS), acreage requirements for an alternative future, and normalized transition probabilities.
Calculation of DAS for parcels is described in Appendix E.
Example: As determined earlier, alternative future 5 has the following hypothetical acreage
requirements for land uses between 2004 and 2014:


500 acres for commercial/industrial uses
6,942 acres in residential uses allocated to home types as follows:
 24.29 acres in high density homes
 38.18 acres in urban homes
 105 acres in suburban homes
 160 acres in rural homes
 975 acres in exurban homes, and
 5,640 acres in agricultural homes.
The set developable parcels available for conversion to a particular use (commercial/industrial or
residential) is identified by imposing the land use policy for alternative future 5 on all parcels.
DAS are then calculated for the set of developable parcels. Normalized adjusted DAS are then
calculated for the set of developable parcels by combining the transition probabilities for
conversion of forested and agricultural lands to built-up uses, and the raw DAS for those parcels.
For example, suppose there are 100,000 acres of forested parcels and 150,000 acres of
agricultural parcels available for development. First, parcels that do not satisfy the land use
policy for alternative future 5 are excluded from the set of developable parcels. Suppose the set
of developable parcels for alternative future 5 contains 75,000 acres of forested parcels and
100,000 acres of agricultural parcels. Normalized DAS for the set of developable parcels are
determined as follows (for simplicity, only two parcels are in the set of developable parcels):
Land cover for
parcel
Agricultural
Forested
Raw DAS
Transition
probability
0.40
0.85
0.85
0.15
Adjusted DAS
(raw DAS x
transition prob.)
0.34
0.13
Normalized
adjusted DAS
0.72
0.28
Since the normalized adjusted DAS is higher for the agricultural parcel than the forested parcel
(0.78 > 0.28), the agricultural parcel is more attractive for development than the forested parcel.
This procedure integrates historical land cover changes, as reflected in the transition
probabilities, with the development attractiveness of the parcel. Separate normalized adjusted
DAS are calculated for the set of developable parcels for each commercial/industrial use and
each home type. The set of developable parcels for each home type contains different parcels
because of the order in which parcels are converted to home types. Five hundred acres of parcels
are selected from the total set of developable parcels for commercial/industrial development
5
based on their adjusted DAS. Similarly, 24.3 acres of parcels are selected from the total set of
developable parcels available for high density homes, etc. Appendix F describes how the ranks
of developable parcels are used to select parcels for conversion.
Five hundred acres of parcels are selected from the total set of developable parcels for
commercial/industrial development based on their DAS. Similarly, 24.3 acres of parcels are
selected from the total set of developable parcels available for high density homes, etc. Appendix
F describes how the ranks of developable parcels are used to select parcels for conversion.
6
Appendix A. Consensus economic growth rates for industries with alternative futures
Consensus growth rates were determined by combining the values specified by individuals in a
subgroup of the Flathead Landscape Analysis Group.
High, moderate and low growth rates, by industry, 2004-2014, Flathead County
Primary Sector
Annual average percentage growth rate
High
Moderate
Low
0.25
0.22
0.15
Farming and
Ranching
Agricultural,
0.09
-0.14
-0.32
Forestry, and
Fishery
Mining
16
12
8
Construction
11
8
5
Manufacturing
7
5
3
(including forest
products)
Transportation,
4
2
0
Communications
and Public
Utilities
Finance,
10
8
6
Insurance, and
Real Estate
(FIRE)
Services
11
9
7
Government
10
8
5
Wholesale Trade
9
5
3
Retail Trade
9
5
3
Annual average
8.78
6.26
3.91
growth ratea
a. Weighted average of industry growth rates with weights given by market shares in 2000.
7
High, moderate and low growth rates by industry, 2014-2024, Flathead County
Primary Sector
Farming and
Ranching
Agricultural,
Forestry, and
Fishery
Mining
Construction
Manufacturing
(including forest
products)
Transportation,
Communications
and Public
Utilities
Finance,
Insurance, and
Real Estate
(FIRE)
Annual average percentage growth ratea
High
Moderate
Low
0.13
0.11
0.08
-0.05
-0.07
-0.16
8
6
4
5.5
3.5
4
2.5
2.5
1.5
2
1
0
5
4
3
5.5
4.5
3.5
5
4
2.5
4.5
2.5
1.5
Services
Government
Wholesale Trade
4.5
2.5
1.5
Retail Trade
Annual average
4.39
3.13
1.95
growth rateb
a. Growth rates for 2014-2024 are one half of growth rates for 2004-2014.
b. Weighted average of industry growth rates with weights given by market shares in 2000.
8
Appendix B. Consensus land use policies for alternative futures
A consensus specification of land use policies was determined by combining information on the
items listed below provided by two individuals (this is not a large enough sample to be reliable,
but was the best that could be done under the circumstances). Some of the items in the original
survey were modified or deleted after the two responses were obtained.
1. The mix of new home types for each land use policy is based on the following home types
(zoning districts are shown in parentheses):






High density homes have a density of 7+ units per acre (similar to R-5, RC-1 and RA-1).
Use 7 units per acre.
Urban homes have a maximum density of 4-7 units per acre (similar to R-3 and R-4). Use
5.5 units per acre (average of 4, 5, 6, and 7).
Suburban homes have a maximum density of 2 units per acre (similar to R-2).
Rural homes have a maximum density of 1 unit per acre (similar to R-1).
Exurban homes have a maximum density of 1 unit per 5 acres (SAG-5) or 1 unit per 10
acres (SAG-10). Use 1 unit per 7.5 acres (average of SAG-5 and SAG-10).
Agricultural homes have a maximum density of 1 unit per 20 acres per unit (AG-20), one
unit per 40 acres (AG-40), and one unit per 80 acres (AG-80). Use 1 unit per 47 acres
(average of 20, 40, and 80).
For the unrestrictive land use policy, the percentage of new homes in each of the five home types
should be:
1. 11 % in high density.
2. 11 % in urban.
3. 18 % in suburban.
4. 23 % in rural.
5. 21 % in exurban.
6. 16 % in agricultural
For the moderately restrictive land use policy, the percentage of new homes in each of the five
home types should be:
1. 17 % in high density.
2. 21 % in urban.
3. 21 % in suburban.
4. 16 % in rural.
5. 13 % in exurban.
6. 12 % in agricultural
9
For the highly restrictive land use policy, the percentage of new homes in each of the five home
types should be:
1. 30 % in high density.
2. 28 % in urban.
3. 18 % in suburban.
4. 9 % in rural.
5. 8 % in exurban.
6. 7 % in agricultural
2. Home setbacks from wetlands
A new home should not be constructed:
1. within 19 feet of a wetland with the unrestrictive land use policy.
2. within 106 feet of a wetland with the moderately restrictive land use policy.
3. within 240 feet of a wetland with the highly restrictive land use policy.
3. Home setbacks from water bodies
A new home should not be allowed:
1. within 19 feet of water bodies with the unrestrictive land use policy.
2. within 77 feet of water bodies with the moderately restrictive land use policy.
3. within 204 feet of water bodies with the highly restrictive land use policy.
B. Land use policies affecting commercial development
1. Setbacks of commercial structures from wetlands
A new commercial structure should not be allowed:
1. within 29 feet of a wetland with the unrestrictive land use policy.
2. within 146 feet of a wetland with the moderately restrictive land use policy.
3. within 337 feet of a wetland with the highly restrictive land use policy.
2. Setbacks of commercial structures from water bodies
A new commercial structure should not be allowed:
1. within 27 feet of water bodies with the unrestrictive land use policy.
2. within 150 feet of water bodies with the moderately restrictive land use policy.
3. within 297 feet of water bodies with the highly restrictive land use policy.
10
C. Land use policies affecting residential and commercial development
1. Land trusts for preservation of farmland, forestland and open space
Suppose Flathead County establishes a fund for purchasing agricultural, forested and open space
lands in the county from willing sellers (as of 2004) that are critical for protecting natural
resources. Money and willing sellers permitting, conservation easements should be purchased on
the following target percentages of critical agricultural and forested lands in each year:
1. 2 percent by 2014 and 4.3 percent by 2024 with the unrestrictive land use policy.
2. 4.8 percent by 2014 and 7.7 percent by 2024 with the moderately restrictive land use policy.
3. 11.9 percent by 2014 and 29.3 percent by 2024 with the highly restrictive land use policy.
Once the agricultural and forested land parcels are determined, the above percentages will be
applied to determine which lands cannot be developed due to conservation easements.
2. Protection of other environmentally sensitive areas, such as national parks, wildlife refuges,
and wilderness areas
For the unrestrictive land use policy, new residential development adjacent to other
environmentally sensitive areas is not restricted. However, land use in these areas must satisfy
other restrictions imposed by setbacks from wetlands and water bodies for the unrestrictive land
use policy, floodplain regulations, and restrictions on home types due to sewer accessibility.
For the moderately restrictive land use policy, the only new residential development allowed
within one mile of other environmentally sensitive areas is urban, suburban, rural, exurban and
agricultural homes. However, land use must satisfy other restrictions imposed by setbacks from
wetlands and water bodies for the moderately restrictive land use policy, floodplain regulations,
and restrictions on home types due to sewer accessibility.
For the highly restrictive land use policy, the only new residential development allowed within
one mile of other environmentally sensitive areas is suburban, rural, exurban and agricultural
homes. However, land use must satisfy other restrictions imposed by setbacks from wetlands and
water bodies for the highly restrictive land use policy, floodplain regulations, and restrictions on
home types due to sewer accessibility.
Policy
Home types allowed
Unrestrictive policy
high density, urban, suburban, rural, exurban, and agricultural
Moderately restrictive policy
urban, suburban, rural, exurban, and agricultural
Highly restrictive policy
suburban, rural, exurban, and agricultural
11
Appendix C. 1985 and 2002 land covers for Flathead County
2002 Land Cover
1985 Land Cover
Class
1985
2002
Water
18336.87
19279.17
Coniferous Forest
251774.1
250184.9
Deciduous Forest
6304.5
6011.28
Cropland
23805.63
12740.85
Grassland/Shrubland
102169.3
102200.7
Barren/Rock
1474.47
2312.46
Urban/Built Up
4585.23
9426.87
0
5478.66
41.58
743.13
Standing Burnt Forest
Ice/Snow
12
Appendix D. Commercial-institutional-industrial space and acreage requirements
1.
Square feet per worker
Total commercial, institutional, and industrial square feet per worker in Montana in 2000
= 737 + 493 = 1,230 sq. ft. per worker in MT in 2000
Source of tables: Nelson, A.C. 2004. Toward a new metropolis: the opportunity to rebuild
America. Paper Prepared for The Brookings Institution Metropolitan Policy Program,
Virginia Polytechnic Institute and State University, Blacksburg, VA.
13
Arthur C. Nelson, A.C. 2004. Toward a new metropolis: the opportunity to rebuild
America. Paper Prepared for The Brookings Institution Metropolitan Policy Program,
Footnotes from Appendix Tables 5 and 7:
Based on footnote ‘a’, it appears workers is not the same as jobs. In particular, workers is less
than jobs because of full-time and part-time jobs.
2.
Acres per square foot of commercial and industrial space in Flathead County.
The following data come from April 2005 CAMA database as determined by Richard Charrier of
CARES.
Parcels with buildings assigned and square feet known:
Parcel Acres: 1,990.506
Parcels: 2,211
Mean Acreage: .900
Maximum Acreage: 104.929
Minimum Acreage: .012
Bldg Square Feet: 62,541,572
Mean Square Feet: 28,287
Maximum Square Feet: 965,725
Minimum Square Feet: 436
1,990.506/62,541,572 = 0.00003182 acres per square feet in Flathead County =.
3.
Workers per job in Montana
Equals the number of workers in 2000 in Montana from Nelson (2004) divided by the number of
jobs in 2000 in Montana from BEA:
Source: Nelson (2004) Appendix Table 5. Commercial and Institutional Square Feet Demand for
Nation, Regions, and States Ranked by the Percentage of Square Feet in 2030 Built Since 2000:
14
Source: BEA.
http://www.bea.doc.gov/bea/regional/reis/action.cfm?catable=CA25&areatype=30000&years=2000&fips
=30000&format=htm#a
Workers per job in Montana in 2000 = 440,000/559,055 = 0.787.
4.
Acres and square feet in commercial, institutional, and industrial facilities per job
Equals sq. ft. per worker in Montana in 2000 (#1) x acres per square feet in Flathead County (#2)
x workers per job in Montana in 2000 (#3)
(1,230 sq. ft./worker)(0.0000318 acres/sq. ft.)(0.787 workers/job) = 0.03078
commercial, institutional, and industrial facilities per job in Montana in 2000
acres in
(0.03078 acres/job)(40,000 sq. ft./acre) = 1,231 sq. ft. in commercial, institutional, and industrial
facilities per job in Montana in 2000
These figures are used in IMPLAN to determine the amount of commercial, institutional, and
industrial facilities per job.
15
Appendix E. Calculation of development attractiveness scores
A. Overview of development attractiveness attributes and scores
The attractiveness of developable parcels for residential and commercial development is
determined based on development attractiveness scores (DAS) estimated using a two-step
process. The first step determines a parcel’s location with respect to infrastructure, primarily
sewers. Parcels are sorted into two categories: (1) sewer accessible parcels located within the
current growth boundaries for incorporated cities (Kalispell, Columbia Falls, and Whitefish) and
unincorporated towns in Flathead County; and (2) non-sewer accessible parcels located outside
the current growth boundaries. Current (2003) growth boundaries have been determined for
Kalispell, Columbia Falls, and Whitefish. Since growth boundaries do not exist for the
unincorporated towns, pseudo growth boundaries are defined as the boundaries for the
unincorporated areas. Allowable uses of developable parcels based on infrastructure are as
follows:
Parcel location
Sewer
accessible (in
growth
boundary)
Non-sewer
accessible
(outside growth
boundary)







Allowable uses
commercial/industrial
high density homes
urban homes
suburban homes
rural homes
exurban homes
agricultural homes
Based on infrastructure, developable parcels can only be converted to commercial/industrial,
high density homes, urban homes, and suburban homes in sewer accessible areas, and to rural
homes, exurban homes and agricultural homes in non-sewer accessible areas.
DAS for parcels where residential uses are allowed are calculated using a multiple attribute
evaluation (MAE) procedure that incorporates five attributes: (1) maximum acceptable distance
from a major highway; (2) maximum acceptable distance from the edge of town; (3) maximum
acceptable distances from amenities (i.e., mountains, lake, river, preserve/park, golf course, ski
resort, forest, and elevation difference); and (4) minimum acceptable distances from disamenities
(i.e., industrial facility or park, mining facility, trailer park, edge of town, railroad tracks, and
airport). Minimum and maximum acceptable distances vary by home class (combination of home
type and tract vs. custom home). Quantification of the effects of these attributes on residential
DAS is described in section B.
DAS for parcels where commercial/industrial uses are allowed are calculated using a MAE
procedure that incorporates two attributes: (1) maximum acceptable distance from a major
highway; and (2) maximum acceptable distance from population centers. Quantification of the
effects of these attributes on commercial/industrial DAS is described in section C.
16
B. Residential DAS
Calculation of residential DAS for parcels is described in three steps, as follows.
1. Minimum and maximum acceptable distances for attributes and attribute weights are based on
responses to a parcel suitability survey administered to developers, real estate professionals,
planners, and others in Flathead County (see part D for attribute values and weights).
2. The DAS for a developable parcel is evaluated based on five major attributes. The following
functions are used to quantify the effects of a parcel’s distance from positive attributes on DAS:
Effects of distance from positive attributes on a parcel’s DAS are modeled assuming the DAS
remains constant when the parcel’s distance from the corresponding attribute is less than the
maximum acceptable distance, and then decreases exponentially with distance if the parcel’s
distance exceeds the corresponding maximum acceptable distance.
The effects of distance from major highway on DAS are modeled using: f(hi, h) = 1 for hi ≤ h,
and f(hi, h) = e-( hi – h) for hi > h, where subscript i designates parcel i. This function indicates that,
other things equal, a parcel’s attractiveness for development decreases when its distance from a
major highway exceeds the maximum acceptable distance (h), and remains constant for distances
below the maximum acceptable distance.
The effects of distance from edge of town on DAS is modeled using: f(ti, t) = 1 for ti ≤ t, and f(ti,
t) = e-(ti – t) for ti > t. This function indicates that, other things equal, a parcel’s attractiveness for
development decreases when its distance from the edge of town exceeds the maximum
acceptable distance (t), and remains constant for distances below the maximum acceptable
distance.
The effects of distance from amenities on DAS is modeled using: f(aik, ak) = 1 for aik ≤ ak, and
f(aik, ak) = e-(aik -ak) for aik > ak where k refers to the lake, river, preserve/park, golf course, ski
resort, or forest amenity attribute. Amenities are desirable attributes of parcels. This function
indicates that, other things equal, a parcel’s attractiveness for residential development decreases
when its distance from the amenity exceeds the maximum acceptable distance (ak), and remains
constant for distances below the maximum acceptable distance. Distances from the seven
amenity attributes are aggregated to obtain parcel i’s weighted average amenity attribute for
home class r:
6
fiar =

wkr f(aikr, ar) + werf(aier, aer),
k
Weights sum to one and the values of fiar range from 0 to 1.
A plot of the functions for positive attributes excluding elevation difference is:
17
f(xi, x)
1
x
xi
x = h, t, ak.
Effects of a parcel’s elevation difference on the DAS are modeled in the opposite way from other
amenities. The effect of elevation on a parcel’s DAS is zero if the elevation difference is less
than the minimum elevation difference and increases linearly as the elevation difference exceeds
the minimum elevation difference. It is modeled using the following function: f(aie, ae) = 0 for aie
≤ ae, and f(aie, ae) = (aie - ae)* for aie > ae, where the asterisk indicates a normalized elevation
difference (i.e., (aie - ae)* = [(aie – ae) - min (aie – ae)]/[max (aie - ae) – min (aie - ae)]). A plot of the
function for elevation difference is:
f(aie, ae)
1
ae
aie
Effects of disamenities on the DAS are modeled using the function: f(dik, dk) = e(dik -dk) for dik ≤
dk, and f(dik, dk) = 1 for dik > dk, where subscript i designates parcel i, and subscript k refers to
disamenity k. This function indicates that the effect of a disamenity on DAS (i.e., f(dik, dk)) is
constant when parcel distance from the disamenity exceeds dk and causes the DAS to decrease
exponentially as the distance decreases from dk. A plot of f(dik, dk) is:
18
f(dik, dk)
1
dk
dik
The weighted distance of parcel i from disamenities for home class r is:
7
fidr= (1/7)  f(dik, drk),
k
where dik is parcel i’s distance from disamenity k and drk is the minimum acceptable distance
from the disamenity k for home class r. This function assumes that all disamenities have equal
weight. Values of fidr range from 0 to 1.
3. DAS for developable parcels for home class r is:
DASir = whrf(hir, hr) + wtrf(tir, tr) + warfiar + wdrfidr,
where (omitting subscript r):
wh = average weight for maximum acceptable distance from a major highway;
wt = average weight for maximum acceptable distance from the edge of town;
wa = average weight for maximum acceptable distance from amenities; and
wd = average weight for minimum acceptable distance from disamenities;
wh + wt + wa + wd = 1 for all home classes. Since weights sum to one and all of the attribute
values (i.e., f(•)) are between 0 and 1, DASir is between 0 and 1.
C. Commercial-institutional-industrial DAS
DAS for commercial/industrial parcels that are sewer accessible are determined based on a
parcel’s proximity to major highways and population centers (i.e., edge of town), and the relative
importance of these attributes (i.e., attribute weights). Parcel distances from these two attributes
are modeled using the same functional forms as used for major highway and edge of town for
residential parcels. DAS for developable parcels in commercial/industrial uses are:
DASic = whcf(hic, hc) + wpcf(tic, tc).
Since whc + wpc = 1, and the attribute values (i.e., f(•)) are in the range 0 to 1, the
commercial/industrial DAS are between 0 and 1.
19
D. Values of attributes and weights for development attractiveness scores3
Residential parcel attractiveness attributes and weights
The attractiveness of developable parcels for residential development is evaluated in terms of
four categories of home types (defined below), tract (spec) and custom homes (defined below),
and five attributes (defined in section B).
Four categories of home types (county zoning districts shown in parentheses)
1. High density and urban homes. High density homes have an average density of 7 units per
acre (similar to R-5, RC-1 and RA-1), and urban homes have an average density of 5.5 units per
acre (similar to R-3 and R-4).
2. Suburban and rural homes. Suburban homes have an average density of 2 units per acre
(similar to R-2), and rural homes have an average density of 1 unit per acre (similar to R-1).
3. Exurban homes have an average density of 1 unit per 7.5 acres, which is the average of 1 unit
per 5 acres (SAG-5), and one unit per 10 acres (SAG-10).
4. Agricultural homes have an average density of 1 unit per 47 acres, which is the average of 1
unit per 20 acres (AG-20), 1 unit per 40 acres (AG-40), and 1 unit per 80 acres (AG-80).
Tract and custom homes
Home types within the tract (spec) and custom home categories are:
Tract homes
Custom homes
High density
Urban
Suburban
-----
Urban
Suburban
Rural
Exurban
Agricultural
Residential attribute values
1. The maximum acceptable distances in miles from a major highway (h):
Home category
High density and urban
Suburban and rural
Exurban
Agricultural
3
Tract homes
0.625
1.17 (suburban only)
Not applicable
Not applicable
Tabled values are averages based on two responses to the parcel suitability survey.
20
Custom homes
0.75 (urban only)
1.375
2.875
4
2. The maximum acceptable distances in miles from the edge of town (t):
Home category
High density and urban
Suburban and rural
Exurban
Agricultural
Tract homes
0.625
1.75 (suburban only)
Not applicable
Not applicable
Custom homes
0.75 (urban only)
0.875
3.5
7.5
3. Maximum acceptable distances in miles from amenities (ak):
High Density and Urban Homes Category
Amenity
Lake
River
Preserve/park
Golf course
Ski resort
Forest
Elevation difference (in feet)
Tract homes
(high density and urban)
Maximum
Relative
acceptable
importance of
distance from “being near”
the amenity
the amenity
15.25
10.25
7.0
0.125
35
7.5
250
0.185
0.154
0.170
0.123
0.093
0.154
0.123
21
Custom homes
(urban only)
Maximum
Relative importance of
acceptable
“being near” the
distance from
amenity
the amenity
17.5
0.125
9.30
0.125
37.5
12.5
250
0.212
0.152
0.120
0.152
0.182
0.121
0.061
Suburban and Rural Homes Category
Amenity
Tract homes
(suburban only)
Maximum
Relative
acceptable
importance of
distance from “being near”
the amenity
the amenity
Lake
River
Preserve/park
Golf course
Ski resort
Forest
Elevation difference (in feet)
17.5
12.5
8.0
5.1
35
7.5
250
Custom homes
(suburban and rural)
Maximum
Relative importance of
acceptable
“being near” the amenity
distance from
the amenity
0.176
0.147
0.190
0.147
0.106
0.118
0.118
17.5
12.5
15.5
12.5
37.5
12.5
250
0.194
0.139
0.190
0.167
0.139
0.111
0.056
Custom Exurban and Agricultural Homes Categories
Amenity
Lake
River
Preserve/park
Golf course
Ski resort
Forest
Elevation difference (ft.)
Exurban
Maximum
Relative
acceptable
importance of
distance
“being near”
from the
the amenity
amenity
20
15
16.75
12.5
37.5
12.5
250
0.147
0.118
0.210
0.147
0.118
0.176
0.088
22
Agricultural
Maximum
Relative
acceptable
importance of
distance
“being near”
from the
the amenity
amenity
9
17.5
18.0
15
40
10
250
0.121
0.091
0.240
0.152
0.121
0.182
0.091
4. Minimum acceptable distances in miles from disamenities (dk):
Disamenity
High density and
urban homes
Tract homes Custom homes
(high density
(urban only)
and urban
homes)
0.625
1.75
5.5
9
0.375
1.5
0.375
0.625
0.225
0.375
.225
0.5
1.5
1.5
Industrial facility or park
Mining facility
Trailer park
Busy highway
Commercial center
Railroad tracks
Airport
Disamenity
Suburban and rural homes
Tract homes
(suburban only)
3
10
1.5
1.25
2.75
1.25
3
Custom exurban
homes
Industrial facility or park
Mining facility
Trailer park
Busy highway
Commercial center
Railroad tracks
Airport
1.5
8.5
1
0.075
2.75
0.75
3
Custom
homes
(suburban and
rural)
5.5
12.5
3
2.75
5.25
1.25
3
Custom
agricultural
homes
3
5
1.5
1.25
7.5
1.25
5.5
Each disamenity receives a weight of 0.143.
Weights for residential attractiveness attributes
Attribute
Minimum
acceptable
distance from a
major highway
Maximum
acceptable
distance from
the edge of
town
High
density and
urban
0.29
Weight
Suburban
Exurban
and rural
0.29
23
Agricultural
0.32
0.18
0.13
0.32
0.29
0.16
Maximum
acceptable
distances from
amenities
Minimum
acceptable
distances from
disamenities
Sum
0.21
0.20
0.32
0.355
0.21
0.16
0.21
0.355
1.00
1.00
1.00
1.00
Commercial/industrial parcel attractiveness attributes and weights
1. The maximum acceptable distance from a major highway is 0.75 miles.
2. The maximum acceptable distance from population centers is 5 miles.
Maximum acceptable
distance from:
Major highway
Population centers
Weight
0.60
0.40
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Appendix F. Procedures for selecting parcels for conversion to developed uses
The order in which parcels are selected from the total set of developable parcels for a particular
land use is based on their development attractiveness scores (DAS), which range from 0 to 1, and
other factors. The set of developable parcels for a particular land use is divided into five groups.
The first group contains developable parcels with the highest 20 percent of scores, the second
group contains parcels with the next highest 20 percent of scores, etc. All developable parcels
within the same group are considered to be equally attractive for development. For example,
acreage required for new urban homes (24 acres in the hypothetical example) is randomly
allocated to parcels such that approximately 80 percent of the acreage in parcels (19.2 acres)
comes from the highest ranked group, and approximately 20 percent (4.8 acres) comes from the
second highest ranked group. When all the parcels in the highest ranked group are developed,
then the second highest ranked group becomes the highest ranked group and the procedure is
repeated. Twenty percent of the land requirement is allocated to the second group because it is
generally not possible for developers to acquire the most attractive land for development due to
the unwillingness of owners to sell, inability to agree on price, and other factors. Acreage
conversions to other home types and commercial/industrial uses are determined in a similar way.
Once a parcel is converted to a particular land use, it is removed from the set of developable
parcels for that use. This acreage conversion procedure was adapted from a landscape study by
Steinitz et al. 2003.
25
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