Minnesotans For Sustainability©

 

Home ] Up ] Feedback Please ] Table of Contents ] Search MFS ] MFS News ]

Sustainable Society:  A society that balances the environment, other life forms, and human interactions over an indefinite time period.

 

 

 

 

 


 

Population Growth and Sprawl in Minnesota

Leon Kolankiewicz
November 30, 2000

 

Does a growing population contribute to urban sprawl? The relationship between population growth and sprawl appears obvious to some but is denied or minimized by just as many.  What has been lacking is a systematic, comprehensive, consistent means of quantifying the role of population growth in sprawl in recent decades.  A forthcoming national study by NumbersUSA will do just that.

Dozens of factors contribute to sprawl, from federal highway subsidies to the pursuit of more affordable housing and better public schools.  All but one of these, population growth, have the net effect of increasing the amount of land consumption per resident, that is, of decreasing density.

The amount of land taken up by a city, town, or any urbanized area is the simple product of the number of residents times the amount of land consumed per resident, as shown in the following equation:

A = P x a

Where: A = Area of urbanized/developed land in acres or square miles

P = Population of the urban/suburban area

a = urbanized land per person (i.e. the inverse of density, which is number of people per unit area of land)

One means of measuring the amount of sprawl then is the increase in ‘A’ over time.  Fortunately, it is easy to measure the amount of overall sprawl because of a painstaking process conducted by the U.S. Bureau of the Census for a half-century.

The forthcoming national study and the figures below rely solely on Census data on Urbanized Areas of the United States to measure Overall Sprawl.  The Census Bureau uses a rather complicated but consistent set of conditions to measure the spread of cities into surrounding rural land.  The Bureau calls the contiguous developed land of the central city and its suburbs an "Urbanized Area."

The relationship between population growth and sprawl can be quantified by comparing rates of change in population and urbanized land area over the same period of time.  The table on the next page makes this comparison for five urbanized areas the Census Bureau has identified in Minnesota.  What it shows is that in Minnesota both population growth and growth in per capita land consumption contribute to sprawl, although there is substantial variation from one city to the next.

Since the Duluth-Superior Urbanized Area actually declined in population from 1970 to 1990, population growth is associated with 0% of the sprawl there; 100% of its sprawl is related to declining population density (rising land consumption per capita).  On the other hand, 100% of the sprawl in St. Cloud from 1980 to 1990 can be explained by population growth, because average density actually rose during that decade. St. Cloud residents were living more closely together on average in 1990 than 1980, but not by enough to accommodate all new residents, and so, development expanded onto open space on the periphery.

 

Urbanized

Area

 

1970

Population

1970

Land Area

(sq. mi.)

1970

Acres per capita

 

1980 Population

1980

Land Area (sq. mi.)

1980

Acres per capita

1990 Population

1990

Land Area (sq. mi.)

1990 Acres per capita

Duluth-Superior

138,352

110.9

0.5130

132,585

132

0.6372

122,971

143.2

0.7453

Fargo-Moorhead

85,446

23.5

0.1760

104,643

45

0.2752

121,336

51.5

0.2716

La Crosse

63,373

23.5

0.2373

67,966

27

0.2542

78,928

34.4

0.2789

Minneapolis-

Saint Paul

1,704,423

721.4

0.2709

1,787,564

980

0.3509

2,079,676

1,063.0

0.3271

Saint Cloud

     

58,375

24

0.2631

74,037

28.7

0.2481

Totals

1,991,594

879.3

0.2826

2,151,133

1,208

0.3594

2,476,948

1,320.8

0.3413

 

 

Urbanized

Area

 

1970-90 Sprawl related to

Population Growth

1970-90 Sprawl

related to Growth in Per Capita Land Consumption

 

1970-80 Sprawl related to

Population Growth

1970-80 Sprawl

related to Growth in Per Capita Land Consumption

 

1980-90 Sprawl related to

Population Growth

1980-90 Sprawl

related to Growth in Per Capita Land Consumption

Duluth-Superior

 

0%

 

100%

 

0%

 

100%

 

0%

 

100%

Fargo-Moorhead

 

45%

 

55%

 

31%

 

69%

 

100%

 

0%

La Crosse

58%

42%

50%

50%

62%

38%

Minneapolis-

Saint Paul

 

51%

 

49%

 

16%

 

84%

 

100%

 

0%

Saint Cloud

NA

NA

   

100%

0%

Weighted Average

 

54%

 

46%

 

24%

 

76%

 

100%

 

0%

The upper table presents raw data from the U.S. Census Bureau’s delineation's of Urbanized Areas in the 1970, 1980, and 1990 censuses. 1990 is the most recent year available. (The 2000 Census Urbanized Area data will be available in two or three years.)

The lower table apportions sprawl, as measured by the growth in urbanized land area over the period given, between shares related to population growth and growth in per capita land consumption.  Three periods are shown: 1970-90, 1970-80, and 1980-90.  One trend in evidence is that average population density declined (i.e. land consumption per resident grew) in the 1970s, contributing to more sprawl than population growth in that decade.  In the 1980s, however, average density rose, which means that population growth was linked to substantially more sprawl in that decade than rising land consumption per resident.

For the cities that were already urbanized areas in 1970, 54% of 1970-90 and 100% of 1980 - 1990 sprawl was associated with population growth.

About the Author

Leon Kolankiewicz is a national environmental/natural resource planner and a former planner with the Orange County (California) Environmental Management Agency. He has a B.S. in forestry and wildlife management from Virginia Tech and an M.S. in environmental planning and natural resources management from the University of British Columbia. He has worked as an environmental professional for more than two decades, including stints with the U.S. Fish and Wildlife service, National Marine Fisheries Service, Alaska Department of Fish and Game. He has written more than 70 articles and reports and is the author of "Where Salmon Come to Die: An Autumn on Alaska's Raincoast" (Boulder, Colorado: Pruett, 1993).
______
Also see on this Website: "Outsmarting Smart Growth"

Home
Up
 

Please send mail to webmaster@mnforsustain.org with questions or comments about this web site. Minnesotans For Sustainability (MFS) is not affiliated with any government body, private, or corporate entity. Copyright © 2002, 2003, 2004 Minnesotans For Sustainability