and it doesn't need to look like shit. but that's the cheapest method, so that's what 'mericans do because freedom.

There is absolutely no reason these ponds cannot be constructed so that they are attractive water features, and still function as flood attenuation, except for a bit more cost.

Forebay . . benched shallows . . then deep . . round rock and reinforced vegetative measures in lieu of limestone rip-rap placed on a 2:1 slope . . .

It always slays me to see one of these monstrosities . . more at home in an Exxon-Mobile refinery . . air-dropped into some high end development named 'Natures Haven' or some such shit.

They can't/won't see the value in doing Stormwater right.

retention (wet) ponds generally hold a permanent pool of water whereas detention (dry) ponds usually remain dry. Both are designed to accommodate runoff while metering outflow differently. Something like that

If they laid any pipe for the water to drain through, that's exactly what it is. It will collect water from runoff and direct it either into the storm drains or to a nearby stream or pond.

https://en.wikipedia.org/wiki/French_drain

Here, we build Freedom Drains!

"darn tootin', this here's 'murica. don't need no lily-livered, poodle-walking, sashay-in frenchies to be namin' our drayuns. they be FREEDOM drayuns dammit, because.... 'murica."

okie-doke, but what then about Welsh drains?

As others said, they're storm water retention ponds. Down here, they don't put boulders in them. We're on the coastal plain, so they just let the water percolate down through the sandy soil. Or, if they're near heavily paved-over areas, they might also drain into the sewer system. They'll also put some cattails and flood-tolerant trees around them, too.

Catches the garbage, silt, and other debris as well as contaminants that will settle on it and be filtered out by the soil so it doesn't run into creeks and waterways.

In Katy TX have them. They are usually filled with water like lakes, and have walking trails and trees around them. Harvey showed their real value: thirty inches of rain since Friday and little flooding out here. If course we benefit from being neighborhoods not much more than twenty years old.