Floods

In the area I live, there is not an extremely high risk of flooding. I do live very near a fiver, but according to the map if it floods it will most likely not reach my home.

Three viable flood control methods for an area like Manhattan are a self closing flood barrier, tidal gates, and groynes.

Self closing flood are pretty self explanatory. They are flood gates that you can install around an area that rise when they detect approaching flood water. They do not require someone to raise them. So even though they are really best for areas with few humans, I think they could be useful in an area like Manhattan. That way they would not block ports or ocean access, until the flood actually got there. It would also look a lot better than a permanent wall.

Tidal gates would be an excellent choice in a coastal area such as New York. They use the change in water level to control water flow. They act kind of like a wall between different waterways, but they allow water and fish and other things to pass through. They utilize a float to close a gate when the water reaches a predetermined level. These would be great for the coast, which could help prevent flooding further inland as well.

Groynes help prevent flooding by keeping beaches from eroding. They can also help limit the flow of water in streams. They could be used to not only protect area in immediate donger of flooding because of  rise in the sea level, but they could also protect areas farther inland. If you put them in the rivers, it would limit the flow of water from the ocean when it rises, protecting the areas along that river.

Of the options I listed above, I think the best method for our area would be self rising flood gates. We aren't really in immediate danger of flooding though, so i do not know if it would be worth the effort. As far as New York goes, I think a combination of groynes and tidal gates could work really well for that area. They would work well together because the groynes would help keep the beaches from eroding, while the tidal gates would keep the rivers from flooding, while still letting things pass through.

https://docs.google.com/document/d/11_BcJSdZCzRYDFmTEyvGJuTxjU9EBVBDCxMe9WGnspY/edit?usp=sharing