Beach nourishment, also called beach renourishment, beach replenishment, or sand replenishment, is a method used to replace sand that has been lost due to erosion or the movement of sand along the shore. Adding more sand to the beach can help protect buildings and other structures near the coast. A wider beach spreads out the force of waves and storm surges, reducing damage from storms, tsunamis, and high tides.
Coastal erosion is the loss or movement of land along the coastline. It happens when waves, currents, tides, wind-driven water, ice, or storm impacts remove sediment and rocks over time. The shoreline can move landward, and this movement can be measured over time scales like tides, seasons, and other short-term cycles.
The Hurricane & Storm Damage Risk Reduction System (HSDRRS) is a flood protection system in southern Louisiana that helps protect the Greater New Orleans area from storm surges. It is designed to reduce the risk of flooding to a level that would occur once every 100 years, meaning there is a 1% chance each year that a storm surge of that size or larger could happen. In 2019, the U.S.
Floodplain restoration is the process of repairing a river’s floodplain to make it as close as possible to its natural state before levees (dikes) were built and wetlands and marshes were drained. The goals of restoring floodplains are to decrease the number of floods, create homes for water animals, improve the quality of water, and help groundwater refill more effectively.
Sponge city (Chinese: 海绵城市) is an urban planning idea created in China by Kongjian Yu. It focuses on using natural systems, such as parks, wetlands, and permeable paving, to manage water and reduce flooding. Instead of relying only on drainage systems, sponge cities use green spaces to absorb rainwater, which helps prevent floods, reduces water shortages, and lessens the heat island effect.
Urban flooding happens when water covers land or buildings in cities or other developed areas. This can occur when heavy rain or storm surges from the ocean cause water to overflow drainage systems, such as storm sewers. Urban flooding can happen anywhere, even in areas not near rivers, lakes, or floodplains.
Bioswales are channels built to collect and move stormwater runoff while removing dirt, trash, and pollution. They also help groundwater refill, reduce flooding and erosion, and provide a place for pollinators like bees and butterflies to live. Bioswales are usually covered with plants, mulch, or drought-resistant plants.
Rain gardens, also called bioretention facilities, are one type of method used to help soil absorb more rainwater runoff. They can also clean stormwater that has been polluted. Rain gardens are special garden areas designed to slow down the speed, reduce the amount, and lower the pollution in runoff from areas that do not let water soak in, such as rooftops, driveways, sidewalks, parking lots, and compacted grass areas.
Green infrastructure, or blue-green infrastructure, is a system that helps solve problems in cities and with the climate by working with nature. This system includes managing rainwater, preparing for changes in the weather, reducing hot temperatures, supporting plant and animal life, growing food, improving air quality, creating energy from natural sources, keeping water clean, and maintaining healthy soil. It also helps people by offering places to relax, providing shade, and offering protection in and around cities.
The United States Environmental Protection Agency (EPA) Storm Water Management Model (SWMM) is a tool that simulates how rainwater and groundwater move over and under the ground in urban and suburban areas. It can model processes such as rainfall turning into runoff, water evaporating, soaking into the ground, and connecting with underground water. These processes are studied in areas like streets, grassy spaces, rain gardens, ditches, and pipes.