Regional differences

High Mountains

These high-elevation areas produce most of the state's runoff and are very sensitive to temperature changes. Snowpack will decline sharply and melt earlier in spring. Higher temperatures will increase water loss through evaporation from plants and soil more than in other regions. Less snowmelt plus more evaporation means much less water available to refill underground aquifers and feed rivers. These mountains create most of New Mexico's water supply, so declining runoff here affects water availability throughout the state downstream.

Northwestern High Desert

Streams in this region that used to flow year-round may become seasonal or dry up completely due to less water and lower underground water levels. Loss of plants makes soil less able to soak up water, leading to less aquifer refilling. Rivers here will carry less water because of higher evaporation and less plant cover. Arroyo formation will increase, causing streams to cut deeper channels that drain wetlands by lowering local groundwater tables.

Rio Grande Valley & Southwestern Basins

River flows will drop significantly due to higher evaporation and earlier snowmelt. The Rio Grande is projected to have 25% less flow on average over the next 50 years above Elephant Butte Reservoir. Warmer temperatures will dramatically increase evaporation from reservoirs—Elephant Butte could lose an additional two feet of water each year, representing a 30% increase in evaporative loss. This means reservoirs will hold less water even when they receive inflows. Higher water needs from plants and crops will further reduce available water supplies.

Eastern Plains

Water loss through evaporation and plant use in this region will be among the greatest in the state. Spring and summer rainfall may decrease when evaporation rates are highest, leading to more water scarcity. This flat region doesn't create much runoff compared to mountains, so it depends heavily on underground aquifers.

Activities to lessen the effects of declining surface water runoff, river flows, and reservoir levels

The following activities can lessen the effects of declining surface water runoff, river flows, and reservoir levels. They can be investigated further at NM WaterTAP.

Add Emergency Water Supply

When surface water runoff, river flows, and reservoir levels decline during droughts, emergency supply agreements provide backup water from neighboring systems. About half of New Mexico's water systems have these arrangements. This alternative source helps communities continue water service when rivers and reservoirs run low during extended dry periods.

Aquifer Storage and Recovery/Managed Aquifer Recharge

ASR/MAR stores excess river water underground during wet periods through injection wells. When rivers run low and reservoirs drop during droughts, stored water is pumped back out. Underground storage prevents evaporation losses common in New Mexico's hot climate, creating a water "savings account" that provides reliable supplies during dry periods.

Build Reuse/Recycled Water Infrastructure

Building water reuse infrastructure treats wastewater so it can be used again for irrigation, parks, and industrial purposes instead of drawing from declining rivers and reservoirs. This creates a drought-proof local water supply that doesn't depend on rainfall or snowmelt. When wastewater is safely reused, it frees up fresh river water for drinking and farming while reducing strain on stressed surface water sources.

Drill New Well

Drilling new wells provides groundwater backup when surface water from rivers and reservoirs runs low. During droughts, communities and farmers pump groundwater instead of relying only on declining surface supplies. This conjunctive use strategy diversifies water sources, helping water systems continue operating when runoff and river flows decrease.

Riparian Management for Water Quality

Riparian management protects streamside vegetation that keeps water temperatures cooler and maintains water quality. Healthy riparian areas with trees and plants shade streams, preventing excessive warming during low flow periods. This becomes critical when runoff and river flows decline, because lower water volumes warm more quickly. Good riparian management helps maintain water quality even with reduced flows.

Shortage Sharing Agreements

Shortage sharing agreements establish fair rules for dividing limited water when runoff, river flows, and reservoir levels drop. Communities with these agreements maintain peace better than those without plans. During droughts when surface supplies decline, predetermined agreements prevent conflicts. About 40 percent of New Mexico's farming areas have sharing procedures for managing shortages.

Transfer Water Rights

Transferring water rights allows purchasing senior water rights through market-based purchases or leases. When surface water runoff and river flows decline, decreasing overall water availability triggers shifts from lower-value to higher-value uses. When surface water runoff and river flows decline, water systems can acquire rights from more senior users to meet needs. This manages declining surface water by diversifying supplies.

Water Banking Agreements

Water banking agreements or temporary place-of-use agreements allow water rights owners to move their allocations to different locations during shortages. Upstream, senior rights holders can temporarily transfer unused water to systems facing severe shortages downstream. This keeps water in rivers longer and prevents excessive pumping of groundwater or draining of reservoirs during droughts.

Watershed Management for Recharge, Runoff and Water Quality

Healthy watersheds help land absorb more water during rain and snowmelt, which recharges underground aquifers. Good soil and vegetation reduce erosion that fills reservoirs with sediment. Stable riverbanks and floodplain connections maintain steady water flow year-round, even during droughts and storms.