Greater New Orleans relies on forced drainage systems to keep dry. This single-purpose approach to stormwater is resource-intensive, yet streets still flood regularly. This approach is also the primary cause of subsidence in the region, and diminishes the value of the area’s waterways and water bodies as public assets.
Flooding is the presence of unmanaged water in streets and properties. With heavy regional rains, the catch basins, pipes, and pumps of existing drainage systems are often overwhelmed. The drainage systems have the capacity to drain 1 inch of rain during the first hour of a storm, and 1/2 inch per hour after that. Catastrophic flooding occurs when floodwalls are breached by surges from outside the hurricane protection system, but flooding from rainfall is much more common. Flooding leads to extensive damage to streets, homes, and businesses throughout Greater New Orleans, as well as millions of dollars in flood insurance claims and high insurance rates.
Subsidence is the sinking of the ground. It damages buildings, streets, and other infrastructure and makes the challenge of pumping stormwater out of the region more difficult. Subsidence is a result of dry soils, largely caused by current drainage practices that pump out every drop that falls as quickly as possible.
For a region built on swampland between river and lake, water is remarkably hard to find. Except for Bayou St. John and the beloved lakes and lagoons of Lafreniere Park, Audubon Park, City Park, Joe Brown Park, and Sidney Torres Park, most of the region’s canals and other waterways provide little value as spaces for public life. The water infrastructure that exists today is in many places unsightly and dangerous. Cheaply constructed outfall pipes poke out from canal banks, ditches are often dry or smothered with weeds, water stagnates, and trash-strewn channels block access between neighborhoods.