Extractions: Modeling/Analytical The Southern Nevada Water Authority (SNWA) Ground Water Management Program uses MODFLOW for analysis of secondary recharge. Because of the dynamic growth within the Las Vegas valley, historical development grids were generated. As a base, the Clark County Assessor's Office maintains coverages and a database of more than 400,000 parcels within Clark County. One item within the database is "construction year," which served as an excellent resource for developing the grids. The "construction year" item only records the year of current development, and there were many properties built in the 1950s and 1960s that were demolished and replaced with new types of development in the 1980s and 1990s. To fill in the gaps and locate missing development, data sets from satellite imagery, historical aerial photography, U.S. Geological Survey 7.5-minute quadrangles, historical maps, and the historical record were used. This produced an eye-opening representation of what has been happening in the valley during the last 50 years.
New Southern California Earthquake Data Center Website New Southern California Earthquake Data Center Website. The SCEDC has developed a new website at a new URL www.data.scec.org. Please http://www.data.scec.org/tmp/recenteqs/
