Data

This dataset is part of a time series of maps that encompasses the development of the entire 20th century. Landuse categories include Urban, Agriculture, Desert, and Recreation. The development of these maps is to describe the nature of the change of each category between years. Based upon available data, the years used for this dataset are 1912, 1934, 1955, 1975, and 1995. Data sources used include U.S. Soil Conservation Service air photos, USGS topographic maps, Glendale Historical Society, Salt River Project historical agricultural data, and Arizona Department of Water Resoures historical agricutlural data.

Step 1. Urban

Boundaries were determined visually off of the 1934 Fairchild Photos from the Soil Conservation Service.

We used Fairchild 1935 Photo's 314, 315, and 316 to determine the 1935 urban boundaries

Amended Plat of Glendale, Maricopa County, Arizona was used to delineate the urban boundary for the City of Phoenix for the 1950s decade

Step 2. Agriculture

Boundaries were determined using two sources: Digital data from the Kent Decree and SRP irrigation Districts. Part of the agricultural area was determined from classes A, B and C of the Kent Decree. Class A identifies lands and a year when the parcel was first cultivated prior to the 1910 Kent Decree and after until urbanization. Class B identified agriculture area that was probably farmed sporadically prior to the completion of the Roosevelt Dam, but farmed consistently after the Dam completion. Class C identified land that was not in cultivation before 1910, but was presumably put into irrigation after Dam completion and up until the 1920s. The other part of the Agricultural area was determined using a digital database of former irrigation districts which included both their size and location. Areas were added if the irrigation district was established prior to 1912.

Irrigation Districts: This information was obtained a complete digital set from SRP. Their sources include a ADWR arcinfo digital file (adwr57) dated 1/98; hardcopy maps from 2 reports which were digitized Water Service Organizations in Arizona (1991) by ADWR and U of A, and Arizona Irrigation District Survey (1997) by SW Argibusiness Serv. Inc. And also maps from several local irrigation companies.

Step 3. Desert

All areas within Maricopa County that were not designated as Urban or Agriculture were classified as Desert.

Step 4. Recreation

The boundaries for the regional parks were derived from the MAG 1995 Existing Landuse spatial data set. The parks that were added for this time period were designated as Parks prior to 1975 as confirmed by the Maricopa County Parks and Recreation Department. The only designated recreation at this time was South Mountain Regional Park.