Making a map of outdoor water use was not an easy task. I could not find information on outdoor water use that would be represented in map form. Therefore, to begin to map this information I had to use a residential zoning map overlayed on an income map. Both these maps can induce a general idea of the lot size. For example, high income residential areas are more likely to have larger lot sizes. Consequently, these larger lot sizes will most likely contain larger irrigation areas. In my research I found that the average single family large lot was approximately 119,000 square feet. Having this data can allow me to use the MAWA formula ( (ETo) x (.62) x (Area) x (.7) ) to provide the number of gallons of water used per year. A similar process is used for medium and low-income single family residential homes.
By doing this type of mapping process I learned the value of overlaying maps. By overlaying maps we are able to determine the relationship between different and sometimes unrelated patches of information. The overlay of information can help guide a better understanding of an area.