Cities that over-pump groundwater can deliberately refill their aquifers by routing stormwater or treated water through infiltration basins — shallow, engineered depressions where water is allowed to pond and slowly soak downward through soil layers into the water table below. This cutaway shows one basin: stormwater collects on the surface, percolates through a filter-sand layer and an unsaturated vadose zone, and eventually reaches the saturated aquifer, raising the water table.
Well-designed infiltration basins are periodically taken offline and scraped or tilled to remove the clogged surface layer — the same principle as backwashing a filter — which is why real-world basins are usually built in rotating pairs or banks.
A cutaway infiltration basin where stormwater ponds on the surface, percolates through filter sand and unsaturated soil, and slowly raises the aquifer water table below.
Basin ponding depth is a balance between storm inflow and the soil's effective infiltration rate; skipping sediment pretreatment lets fine particles clog the basin floor, cutting that rate and forcing more water to pond or run off instead of recharging groundwater.
Set storm intensity, basin footprint area and soil hydraulic conductivity, then toggle the sediment forebay on or off. Watch the pond depth, clogging layer and glowing infiltration droplets respond, and see the aquifer water table rise as recharge accumulates.
Infiltration basin design is fundamentally a race between hydraulic conductivity and clogging — engineers size basins generously and schedule maintenance precisely because the "sustainable" infiltration rate of a real basin is always lower than a lab-measured soil permeability.