January 11, 2023

Proposed Rio Grande settlement relies on an index-based approach to water deliveries

Laura Paskus

Downstream of Elephant Butte Dam, water issues get even trickier.

The terms of the proposed settlement between New Mexico, Texas and Colorado regarding Rio Grande water usage and groundwater pumping was released to the public Monday afternoon following a court order.

The 92-page document outlines both the terms of the agreement and the history of the U.S. Supreme Court case. About nine years ago, Texas sued New Mexico over water rights. The case made its way to the U.S. Supreme Court.

The United States opposes the settlement, as do the irrigation districts like Elephant Butte.

The document describes the settlement as “an index-based approach” that would clearly define “the rights and obligations of New Mexico and Texas below Elephant Butte Reservoir.”

Texas has alleged that New Mexico has violated the Rio Grande Compact, including allowing water that was apportioned to Texas through the Compact to be depleted through diversions and groundwater pumping.

New Mexico has also argued that Texas is violating the terms of the Rio Grande Compact through unauthorized diversions of Rio Grande water as well as groundwater pumping.

Under the proposed index approach, the annual release from Caballo Dam, located downstream of Truth or Consequences, will be used to determine how much water New Mexico is required to send downstream to Texas on an annual basis.

The index would include two parts. One part would establish how much New Mexico is obligated to deliver to Texas and the other part would measure how much water Texas actually receives. The measurements of water Texas receives will be based upon readings at the El Paso Gage.

The settlement would also allow New Mexico to fall behind on deliveries to Texas as long as it is within set limits. There are also triggering points within those set limits for actions that New Mexico would have to take.

It also includes provisions for if New Mexico delivers more water than required to Texas.