Gov. Jerry Brown signed historic groundwater legislation Tuesday, imposing new rules in the Golden State that could limit how much water commercial and residential users are allowed to pump from underground aquifers — a move decades in the works, spurred this year by California’s drought. The new laws, which take effect in January, will require local government officials to ensure use of groundwater basins is sustainable, protecting underground reserves and averting other environmental damage. The regulations could have a ripple effect on thousands of farmers and ranchers across the North Coast.