Oil workers on a rig platform in Colorado. Stephen Collector | Getty Images

Colorado drillers are gearing up for a fight after Democratic lawmakers proposed overhauling the state's oil and gas commission and reforming regulations that could create new roadblocks to fossil fuel development. Two of the state's top Democrats introduced the legislation late Friday. They are calling Senate Bill 181 — Protect Public Welfare Oil and Gas Operations — "the most meaningful changes to oil and gas regulations Colorado has seen in over 60 years." The move comes just months after the Colorado oil and gas industry celebrated the defeat of new restrictions on drilling in a referendum in November.

Colorado's communities simply cannot afford to wait any longer. ... These common-sense reforms will ensure the industry operates in an accountable and cooperative manner." Steve Fenberg Colorado state majority leader

The legislation could curtail drilling in one of the nation's top oil and natural gas producing states, where advanced technology like hydraulic fracturing has sparked a production boom over the last decade. That could affect Colorado-focused frackers and larger drillers with a footprint in the state, like Anadarko Petroleum and Noble Energy. The bill would give cities and counties more influence over regulation, including inspecting oil and gas facilities and imposing fines over spills. It would also change the mission of the Colorado Oil and Gas Conservation Commission from fostering the development of the state's fossil fuels to regulating the industry. The lawmakers also propose overhauling the powerful commission's makeup, cutting the number of members required to have industry experience from three to one. They would require at least one member of the commission to have training in several fields, including wildlife and environmental protection, soil conservation and public health. Another measure would raise the threshold for the number of mineral rights holders that would need to give their approval before drillers can tap a shared pool of oil and gas, making it potentially more difficult to develop some reserves. "Colorado's communities simply cannot afford to wait any longer," said Colorado State Majority Leader Steve Fenberg, who co-sponsored the bill with House Speaker KC Becker. "These common-sense reforms will ensure the industry operates in an accountable and cooperative manner," Fenberg said in a statement.