In a single-paragraph assent this week, the U.S. Supreme Court accepted a deal between Texas and New Mexico, ending the 13-year lawsuit between the states and the federal government over the waters of the Rio Grande. With the dismissal of the case, the deal establishes new rules in the stretch of Rio Grande below Elephant Butte, an area reshaped by water scarcity and agriculture. Among other agreements, the parties will divide irrigation water into a 57-43% split, with the majority going to New Mexico farmers. The agreement also mandates less groundwater pumping by New Mexico. … Under the settlement, New Mexico will need to reduce groundwater pumping in the Lower Rio Grande by 18,200 acre-feet within the next 10 years.