The RPC’s region comprises approximately 4,000 square miles of land and 4,700 square miles of water across eight parishes: Jefferson, Orleans, Plaquemines, St. Charles, St. Bernard, St. John the Baptist, St. Tammany, and Tangipahoa. The combinations of these parishes vary depending upon which designation we are representing.
Approximately half of the non-water geographic area is marsh soil, leaving only 1,000 square miles of solid land. Of the readily developable land, the average population density is approximately 1,200 persons per square mile; however, more densely populated urban areas average nearly 3,900 persons per square mile.
Coastal Louisiana wetlands make up the seventh largest delta on Earth and support the largest commercial fishery in the lower 48 states (USGS).
According to the National Oceanic and Atmospheric Administration (NOAA) “Louisiana lost more than 160 square miles (over 100,000 acres) of wetland area to water during this 20-year period [1996-2016]. Much of that includes the marshes that were impacted by Hurricane Katrina, which have yet to recover. Thirty-two percent of Louisiana is wetlands, and 25 percent is water, for a total of over 50 percent of the state.“
The Louisiana Coastal Protection and Restoration Authority (CPRA) serves as the entity responsible for integrating hurricane protection, storm damage reduction, flood control, coastal protection and restoration efforts, and associated infrastructure construction and maintenance for the state.
Elevation data is obtained via optical remote sensing technology, known as Light Detection and Ranging (LiDAR). LiDAR allows for the measurements of distance. The United States Geologic Survey (USGS) provides LiDAR datasets that are available for download at the USGS LiDAR Explorer website.
High resolution imagery ranging from three-inch to one-foot pixel is used throughout the region to provide an accurate background for line work being produced through local efforts. High resolution imagery can be downloaded from the United States Geological Survey (USGS).
National Geodetic Survey (NGS) Data Explorer and the Louisiana Spatial Reference Center (LRSC) also provide information on bench mark elevations and additional Global Positioning System (GPS) sites in coastal Louisiana for the area south of Interstate 10.
The RPC facilitates the development of data sets for GIS use through cooperative endeavors with federal, state and local agencies. The RPC provides data to local governments and facilitates local data sharing. Published data, maps, and interactive applications can be found on the RPC Mapping Resources webpage.
The region’s population has experienced significant changes during the last 50 years. The population increased dramatically during the 1960s and 1970s, primarily due to the growth of the oil and gas industry. In the early 1980s, the region encountered a significant decline in population, attributed to the oil bust. Prior to Hurricanes Katrina and Rita in 2005, the region maintained a population of approximately 1.3 million. Katrina and Rita amplified pre-existing shifts in population: Orleans, Plaquemines and St. Bernard parishes endured dramatic population losses, whereas St. Charles, St. John, St. Tammany, and Tangipahoa parishes gained residents. The current population of the region is approximately 1.3 million.
| Area | Census 1990 | Census 2000 | Census 2010 | Census 2020 |
|---|---|---|---|---|
| Louisiana | 4,219,973 | 4,468,976 | 4,533,372 | 4,657,757 |
| Jefferson | 448,306 | 455,466 | 432,552 | 440,781 |
| Orleans | 496,938 | 484,674 | 343,829 | 383,997 |
| Plaquemines | 25,575 | 26,757 | 23,042 | 23,515 |
| St. Bernard | 66,631 | 67,229 | 35,897 | 43,764 |
| St. Charles | 42,437 | 48,072 | 52,780 | 52,549 |
| St. John the Baptist | 39,996 | 43,044 | 45,924 | 42,477 |
| St. Tammany | 144,508 | 191,268 | 233,740 | 264,570 |
| Tangipahoa | 85,709 | 100,588 | 121,097 | 133,157 |
| TOTAL | 1,350,100 | 1,417,098 | 1,288,861 | 1,384,810 |
