Can Wells be used for Draining Roads?. 3

[Oson]

In a recent visit I made to a Settlement projects in the Island of Abaco, The Bahamas, I was surprised to see that all the Streets and Roads drain to wells. Approximately every 1,000 meters of roads they drill a 14" Diameter Well close to the center line of the road or Street, Culverts are placed from the lateral drains of the road towards the well, making something like a tee, actually the two ends of the culvert are inlets; a grill is placed on top of the well, but since is under the road is very difficult to reach for cleaning.
This particular Island is narrow and very long, close to the sea the soils are sandy but as you move away from the sea soils are calcareus (Marl), terrain is actually very low maybe 14 meters above sea level.
I have never seen something like this, and thought that maybe in this forum somebody can explain why is it done this way and if the system is really efficient.

 

[epongra2]

I worked in Hawaii for a while, and I saw drywells used for storm water runoff in a number of rural areas on the outer islands. I was told that this was the preferred method, as both the overburden and the underlying basalts seemed to percolate pretty well.

There were guidelines in place for this use of drywells. One of them was a not-so arbitrary line that marked where the use of drywells for stormwater runoff could not be used above (in an altitude sene) this line. This line was established so that the runoff would not find its way into the bedrock aquifers that are used for the water supply.

 

[zabrab]

In the US, it would be a Class V injection well.

http://www.epa.gov/safewater/uic/pdfs/fact_class5_stormwater.pdf

 

[cvg]

it is done quite frequently here, but only to drain retention basins; and only when the soil will percolate well. drywells usually can't handle peak flows without a large chamber or basin to handle the surge.