proposed pocket parks raster analysis

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Percent of Households Living Beneath Poverty Level A field in the Census Bureau tract data was created to match the TIGER Shapefiles for census tracts. The table was joined to the shapefiles, exported to a geodatabase, and then reimported to display attribute values. A field was added to display the number of households below poverty level per total number of households. The layer was converted to a raster based on this ratio, and then normalized using raster calculator by dividing the raster by the highest value, resulting in a scale from 0 to 1, where one reflects the highest percent of households below poverty level. Need A suitability raster based on need was created using raster calculator. The raster of areas not served was multiplied by the sum of population density and percent of households living beneath poverty level, so that areas already served would have a need value of 0, and the remaining areas would have a need value ranging from 0 to 2. The need raster was then reclassified with the natural breaks method into 5 classes, and converted into polygons. RESULTS AND CONCLUSION Parcels Travis Central Appraisal District parcels were selected by attribute to produce a set of parcels that are more than 0.10 acres but less than 2 acres, and undeveloped. They were further selected by location to produce a set that are less than 10 meters from a street centerline (to reflect parcels that are connected to the city streets network). The suitable parcels were then spatially joined to the need polygons, and selected by attribute to produce a set of suitable parcels with the highest need value of 5. As a last consideration, a buffer of 0.25 miles around highways and expressways was created, and the remaining parcels selected by location to remove those within the buffer zone. Areas not served by existing parks A 0.25 mi buffer was created around existing parks, and an envelope created around the buffer. The buffer and the envelope were unioned, and the attributes reclassified so that a location with a value of 1 is outside the service area, while a location with a value of 0 is within the service area. The union was then converted to a raster. Population Density Area was calculated for each census block group, and a field added to display the population density as total population per area for each group. The layer was converted to a raster based on population density, and then normalized using raster calculator by dividing the raster by the highest value, resulting in a scale from 0 to 1, where 1 reflects the highest population density. Elizabeth Wesley PROPOSED POCKET PARKS DATA SOURCES Where would Batman live in Austin, Texas? BACKGROUND CARTOGRAPHIC MODEL METHODS Austin has experienced considerable growth in recent years, and as a result has fallen behind national standards for park accessibility. Although Austin ranks high nationally in total acreage of parkland it ranks low in percentage of population living within walking distance of parks and parks per capita. As urban density continues to increase, parks within walking distance become more important, especially within Austin’s urban core. Parks foster a sense of community, increase well being, lower childhood obesity rates, and nurture environmental stewardship. The City of Austin seeks to serve more residents by developing new pocket parks. Pocket parks are specifically defined as being less than 2 acres in size and having a walking-distance service area of ¼ of a mile. This study seeks to find parcels suitable for development as new pocket parks inside the urban core of Austin, TX, within the areas of greatest need. Capital Area Council of Governments, http://www.capcog.org City of Austin, ftp://ftp.ci.austin.tx.us/GIS-Data/Regional/coa_gis.html American Fact Finder, http://factfinder2.census.gov/faces/nav/jsf/pages/index.xhtml Census Bureau, http://www.census.gov/geo/maps-data/data/tiger.html In order to deal with large datasets from varying sources, all data was clipped to the study area. REFERENCES Blake, Alison. Pocket Parks. http://depts.washington.edu/open2100/pdf/2_Open SpaceTypes/Open_Space_Types/pocket_parks.pdf. Accessed: 24 April 2013. City of Austin. 2011. Imagine Austin Comprehensive Plan. ftp://ftp.ci.austin.tx.us/ npzd/Austingo/web_IACP_full_reduced.pdf. Accessed: 1 April 2013. City of Austin Urban Parks Workgroup. 2011. Urban Parks Workgroup: Report Recommendations. https://www.austintexas.gov//sites/default/files/files/Capital_Pl anning/Bond_Development/Parks_Open_Space_Committee/urban-parks- workgroup-final-report.pdf. Accessed: 1 April 2013. Austin’s urban core has been defined empirically for the purpose of this study based on population density and major arterials. Suitable parcels will be defined as those that are: under 2 acres in size greater than 0.10 an acre in size undeveloped connected to the network of city streets not within 0.25 miles of a highway Need will be defined as a mathematical function of: areas not served by existing parks population density percent of total households living below the poverty level The analysis resulted in the selection of 50 suitable parcels. All of the parcels are within an area that is East of IH-35, and bounded to the North by U.S. Hwy 290 and the South by State Hwy 71. Each of these parcels would be a good candidate for infill parkland. Infill development involves the use of vacant lots within urban areas. Only 37% of the population that reside within Austin’s urban core live within walking distance of a park, in contrast to 90% in U.S. leading cities. In order to meet these high standards, the City of Austin must add 58 new neighborhood or pocket parks. In the Imagine Austin Comprehensive Plan, adopted by the Austin City Council June 15, 2012, six core principles for action are listed. Among them are: integrate nature into the city develop as a healthy community sustainably manage environmental resources. The addition of parkland facilitates these actions. With a population that is projected to double within the next three decades, the City of Austin is in a position to make decisions now that will have far reaching impacts on the future of the City. Austin’s green spaces are an important part of its identity, and access to parkland is a key factor in livability. Pocket parks are a vital asset to neighborhoods and communities, and increasing their numbers will help maintain and enhance the quality of life in Austin, and help protect it’s future.

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Page 1: Proposed Pocket Parks Raster Analysis

Percent of Households Living Beneath Poverty Level A field in the Census Bureau tract data was created to match the TIGER Shapefiles for census tracts. The table was joined to the shapefiles, exported to a geodatabase, and then reimported to display attribute values. A field was added to display the number of households below poverty level per total number of households. The layer was converted to a raster based on this ratio, and then normalized using raster calculator by dividing the raster by the highest value, resulting in a scale from 0 to 1, where one reflects the highest percent of households below poverty level.

Need A suitability raster based on need was created using raster calculator. The raster of areas not served was multiplied by the sum of population density and percent of households living beneath poverty level, so that areas already served would have a need value of 0, and the remaining areas would have a need value ranging from 0 to 2. The need raster was then reclassified with the natural breaks method into 5 classes, and converted into polygons.

RESULTS AND CONCLUSION

Parcels Travis Central Appraisal District parcels were selected by attribute to produce a set of parcels that are more than 0.10 acres but less than 2 acres, and undeveloped. They were further selected by location to produce a set that are less than 10 meters from a street centerline (to reflect parcels that are connected to the city streets network). The suitable parcels were then spatially joined to the need polygons, and selected by attribute to produce a set of suitable parcels with the highest need value of 5. As a last consideration, a buffer of 0.25 miles around highways and expressways was created, and the remaining parcels selected by location to remove those within the buffer zone.

Areas not served by existing parks A 0.25 mi buffer was created around existing parks, and an envelope created around the buffer. The buffer and the envelope were unioned, and the attributes reclassified so that a location with a value of 1 is outside the service area, while a location with a value of 0 is within the service area. The union was then converted to a raster.

Population Density Area was calculated for each census block group, and a field added to display the population density as total population per area for each group. The layer was converted to a raster based on population density, and then normalized using raster calculator by dividing the raster by the highest value, resulting in a scale from 0 to 1, where 1 reflects the highest population density.

Elizabeth Wesley

PROPOSED POCKET PARKS

DATA SOURCES

Where would Batman live in Austin, Texas?

BACKGROUND

CARTOGRAPHIC MODEL

METHODS Austin has experienced considerable growth in recent years, and as a result has fallen behind national standards for park accessibility. Although Austin ranks high nationally in total acreage of parkland it ranks low in percentage of population living within walking distance of parks and parks per capita. As urban density continues to increase, parks within walking distance become more important, especially within Austin’s urban core. Parks foster a sense of community, increase well being, lower childhood obesity rates, and nurture environmental stewardship. The City of Austin seeks to serve more residents by developing new pocket parks. Pocket parks are specifically defined as being less than 2 acres in size and having a walking-distance service area of ¼ of a mile. This study seeks to find parcels suitable for development as new pocket parks inside the urban core of Austin, TX, within the areas of greatest need.

•  Capital Area Council of Governments, http://www.capcog.org •  City of Austin, ftp://ftp.ci.austin.tx.us/GIS-Data/Regional/coa_gis.html •  American Fact Finder, http://factfinder2.census.gov/faces/nav/jsf/pages/index.xhtml •  Census Bureau, http://www.census.gov/geo/maps-data/data/tiger.html

In order to deal with large datasets from varying sources, all data was clipped to the study area.

REFERENCES Blake, Alison. Pocket Parks. http://depts.washington.edu/open2100/pdf/2_Open

SpaceTypes/Open_Space_Types/pocket_parks.pdf. Accessed: 24 April 2013. City of Austin. 2011. Imagine Austin Comprehensive Plan. ftp://ftp.ci.austin.tx.us/

npzd/Austingo/web_IACP_full_reduced.pdf. Accessed: 1 April 2013. City of Austin Urban Parks Workgroup. 2011. Urban Parks Workgroup: Report

Recommendations. https://www.austintexas.gov//sites/default/files/files/Capital_Pl anning/Bond_Development/Parks_Open_Space_Committee/urban-parks- workgroup-final-report.pdf. Accessed: 1 April 2013.

Austin’s urban core has been defined empirically for the purpose of this study based on population density and major arterials.

Suitable parcels will be defined as those that are: •  under 2 acres in size •  greater than 0.10 an acre in size •  undeveloped •  connected to the network of city streets •  not within 0.25 miles of a highway Need will be defined as a mathematical function of: •  areas not served by existing parks •  population density •  percent of total households living below the poverty level

The analysis resulted in the selection of 50 suitable parcels. All of the parcels are within an area that is East of IH-35, and bounded to the North by U.S. Hwy 290 and the South by State Hwy 71. Each of these parcels would be a good candidate for infill parkland. Infill development involves the use of vacant lots within urban areas. Only 37% of the population that reside within Austin’s urban core live within walking distance of a park, in contrast to 90% in U.S. leading cities. In order to meet these high standards, the City of Austin must add 58 new neighborhood or pocket parks. In the Imagine Austin Comprehensive Plan, adopted by the Austin City Council June 15, 2012, six core principles for action are listed. Among them are: •  integrate nature into the city •  develop as a healthy community •  sustainably manage environmental resources.

The addition of parkland facilitates these actions. With a population that is projected to double within the next three decades, the City of Austin is in a position to make decisions now that will have far reaching impacts on the future of the City. Austin’s green spaces are an important part of its identity, and access to parkland is a key factor in livability. Pocket parks are a vital asset to neighborhoods and communities, and increasing their numbers will help maintain and enhance the quality of life in Austin, and help protect it’s future.