Providing a controlled source of water for the wetlands is necessary to restore Hamakua Marsh. One possible source may be to tap an aquifer which is an underground reservoir. The water that reaches these underground chambers is usually cleaner than surface water. Many pollutants are filtered out as the water passes through the soil. To tap the underground water, wells are dug until they reach the top level of the aquifer, this is called the water table. The water table has peaks and valleys that follow the shape of the surface land. However, when a lot of water is pumped from an aquifer, or during dry periods, the water table sinks lower.

A source of water for wetlands comes from run off. Water flows into Hamakua Marsh causing the marsh to fill with water. The water slowlys sinks into the soil and gets trapped in the clay ( the dark brown line in the picture to the right).The water that is not being stored in the clay, goes into aquifers (the small yellow circles in the picture to the right).

A well that taps into an aquifer is may be an option for providing water to Hamakua Marsh. One challenge is that the hydric, or very dry soil, and clay might dry out. Another disadvantage of a well, might be the noise from the well pump. The noise could keep birds from being attracted to the marsh. Another disadvantage of a well, is that it could tap into another aquifer already in use.

Water may be dispersed throughout the marsh by using a French drain. This is a tunnel that goes underground and is filled with gravel. A French drain can be used to transport water from one place to another. French drains prevent evaporation, and helps the vegetation above ground. However, French drains are slower at transporting water from one place to another. A French drain cleans the water that goes through it. It also keeps the soil moist, and prevents flooding.