As the nation’s two largest reservoirs have fallen to all-time lows, the Bureau of Reclamation has made adjustments, including a suspension of releases from Glen Canyon Dam to simulate historic flows.

But the agency is expected to resume the practice next week.

Before Glen Canyon Dam was built, the amount of water in the Colorado River varied dramatically.

Spring runoff brought high flows, for example.

The Bureau of Reclamation started to recreate those fluctuations in the 1990s, but suspended them as Lake Powell dropped to record lows.

With a wet winter bringing generous snowpack to the Rockies, the Bureau of Reclamation is expected to authorize a springtime release.

Western conservation groups have applauded the decision.