Final answer:
Rivers and irrigation are the primary sources of groundwater recharge in the Snake River Plain.
Step-by-step explanation:
Groundwater is a significant reservoir of fresh water that exists in the pores between particles in sand and gravel or in the fissures in rocks. Rivers and irrigation are the primary sources of groundwater recharge in the Snake River Plain.
When it rains or surface water is deliberately pumped into the ground, it infiltrates the ground and eventually replenishes the groundwater in the aquifers. This groundwater is often used for drinking and irrigation purposes.