Question

Lake Waiua is Hawaii's only alpine lake. It has (approximately) vertical sides and a 7000 m² area.

Between 2010 and 2013, its depth declined from 3m to 0.3 m.

Imagine that the water that disappeared from the lake between 2010 and 2013 all drained vertically into a completely dry soil layer beneath the lake (porosity ϕ=0.5). Assume that this drainage caused soils to become completely saturated, how much would the height of the water table beneath the lake increase?

Answer 1