Abstract: In certain embodiments, a sand-boil filter includes a hollow, conical, water-porous structure made of a mesh material having spaced mesh holes. The filter is inserted narrow-end down into a sand boil to allow water to flow from the ground through the mesh material and out the top of the sand boil, while blocking solid matter larger than the mesh holes from passing through the mesh material. In some implementations, the filter is filled with gravel that holds the filter in place while allowing water to flow out of the sand boil. Such filters prevent sand boils from growing while relieving the underground hydrostatic pressure that created the sand boil in the first place and inhibiting subterranean erosion that can cause failure of a nearby levee. The conical shape provides relatively large surface area that inhibits clogging and allows each filter to be used for a range of different sand-boil sizes.

Abstract: In certain embodiments, a sand-boil filter includes a hollow, conical, water-porous structure made of a mesh material having spaced mesh holes. The filter is inserted narrow-end down into a sand boil to allow water to flow from the ground through the mesh material and out the top of the sand boil, while blocking solid matter larger than the mesh holes from passing through the mesh material. In some implementations, the filter is filled with gravel that holds the filter in place while allowing water to flow out of the sand boil. Such filters prevent sand boils from growing while relieving the underground hydrostatic pressure that created the sand boil in the first place and inhibiting subterranean erosion that can cause failure of a nearby levee. The conical shape provides relatively large surface area that inhibits clogging and allows each filter to be used for a range of different sand-boil sizes.