that dusty patch of white behind me is where the water should be. with reservoirs running dry, farmers are turning to groundwater. over time, groundwater accumulates in vast underground aquifers. but no you, over the past few years, groundwater levels have dropped 50 feet or more as farmers drill deeper and deeper to access it. today we do set in law a framework that has been resisted for long, long time. since before my father was even governor. reporter: just last year, california became the last state in the west to regulate groundwater usage. the state s first-ever mandatory water restrictions soon followed. we re in an historic drought, and that demands unprecedented action. reporter: a 25% reduction in water usage state wide has forced residents and businesses to cut back. farmers with rights to california water dating back to over a century ago are also facing restrictions for the first time since 1977.
california water dating back to over a century ago are also facing restrictions for the first time since 1977. as the mayor of california s largest city told me, examining water usage will help offset the crisis. we ve added in the last 45 years a million residents without having to consume a single drop of water more. so it s changing it s true. we have 3 million to 4 million more people in last 45 years and we consume the same amount of water as back then because so much water is wasted. reporter: some are looking at the very industry that uses up so much of the state s dwindling resource. half of california s farms still use the antiquated flood and furrow techniques where you literally lip up the loose gates and let the water flood your warm. you used to use flood irrigation. explain the difference. flood irrigation goes on top of the surface and have you no
i m standing in front of peter s canyon reservoir and that dusty patch of white behind me is where the water should be. with reservoirs running dry, farmers are turning to groundwater. over time, groundwater accumulates in vast underground aquifers. but no you, over the past few years, groundwater levels have dropped 50 feet or more as farmers drill deeper and deeper to access it. today we do set in law a framework that has been resisted for long, long time. since before my father was even governor. reporter: just last year, california became the last state in the west to regulate groundwater usage. the state s first-ever mandatory water restrictions soon followed. we re in an historic drought, and that demands unprecedented action. reporter: a 25% reduction in water usage state wide has forced residents and businesses to cut back. farmers with rights to california water dating back to over a century ago are also