Water Flows Into Colorado River Delta in Historic First

Pulse flow on the Colorado River comes through the Morelos Dam
The historic “pulse flow” on the Colorado River comes through the Morelos Dam on March 23. (Photograph by EDF)

Sunday March 23, 2014, at a little after 8 am, the gates at Morelos Dam on the Mexico-Arizona border were opened for the first time in history for the purpose of allowing the Colorado River to flow downstream into its delta to water the plants and animals that live there.  A crowd of more than 100, many from the local community, plus a handful of reporters and water workers from afar, waited just downstream.

A cheer went up when the water began to pour down, first in a trickle, and then a steady gushing flow.  It took a long time for the institutions that manage the Colorado River to make this happen.  Now we have the chance to see how long it takes the river to move downstream, and how far it goes. (See “Historic ‘Pulse Flow’ Brings Water to Parched Colorado River Delta.”)

(Photograph by EDF)
Finding the reach of the pulse flow. (Photograph by EDF)

Later in the day, after some excellent adobada tacos, a few of us drove downriver to look for the front of the flow.  We found it about 18 river miles below the dam, cool and clear.  A lot of the flow is soaking into the parched, sandy channel, and downstream progress is slow but steady.  The water was cool and clear.

Dry channel of Colorado River Delta
The dry channel of the Colorado. (Photograph by EDF)

That water we found was remarkable, because the riverbed is usually dry.  The river hasn’t flowed regularly here since 1960.

Colorado River upstream of Morelos Dam
The Colorado upstream of the Morelos Dam. (Photograph by EDF)

Today, I was fortunate to hitch a ride on a Lighthawk mission flight over the river.  There is typically a small amount of water in the channel here due to the high groundwater table, but it doesn’t flow, it just sits there.  Today it was looking like a river.

Braids appear in the Colorado River
Braids appear in the Colorado thanks to the pulse flow. (Photograph by EDF)

Farther downstream the river was finding its meanders and backwaters, sating a landscape that has long been water-starved.

Colorado River
A river returns. (Photograph by EDF)

At about noon, we saw the river’s front, approximately 20 river miles downstream from the dam.  The water has to advance a few more miles before it reaches San Luis Rio Colorado, a small city that straddles the river about 24 river miles downstream from the dam.  Imagine living in a city named after a river that has disappeared!

Someone held a riverbed cleanup there yesterday, and I’ve heard reports that locals have been coming down to the dry channel all day, wondering when the water will arrive.  I think it will be there soon!


  1. Kevin Kirkpatrick
    United States
    March 15, 11:34 am

    I find the comments interesting and yet no one sees their part in the loss of river water in the West. If you live there you use that water that has been caught behind the dams, the electricity to air condition that hotel room where you stayed to write this story and all the energy for the aluminum for the airplane parts to get you there and overhead of the stream. We all are guilty of raping the planet. Some of us just recognize it and accept it as part of our lives now that cannot be changed. No one is going back to post electric or post oil days. And Yes, I am writing this on a lap top made from oil and minerals mined from the land and powered by electricity from oil, gas and dams.

  2. John Gottes
    Whittier, Califonria
    April 3, 2014, 6:18 pm

    The actual point where the river reaches the Sea of Cortez is a bit hard to locate. The lower Delta is very flat, and tides in the area range from 6′ (during neap tides) to almost 25′ during spring tides. Also, the change from hi tide to low tide occurs about every 6 hours. So, last Friday, at 1:30pm we had hi tide; by 7:30pm the ocean level was 22 feet lower. 6 hrs later the tide was back up 22 feet higher.
    When you have a very flat landscape, the tidal changes cause the water to rush back & forth up & down the channel, so that the “sea shore” moves up & down the channel many miles several times a day.

    Also, in the lower delta, there is a fair amt of surface water and agricultural runoff, which will make determining exactly what is and what is not the Colorado River a bit difficult.

    Finally, access to the area is a bit difficult. I’ve heard you can drive across the mud flats . . . Hope to try this month!

  3. mike maurer
    New Mexico
    April 2, 2014, 12:13 pm

    I too would like to know when it gets to the Sea of Cortez

  4. Amy Crawford
    United States
    March 28, 2014, 6:39 pm

    Drove over to the Morelos Dam this afternoon, truly a sight to see! More pictures, please!

  5. Cheryl Bradstreet
    Yuma, AZ
    March 28, 2014, 2:42 pm

    Jennifer or others in the know: What is the approximate timing of when the water will reach the Sea of Cortez? Several people I know would love to be there for the historic occasion.

  6. conchy
    March 28, 2014, 7:14 am

    Let nature be

  7. sean
    March 27, 2014, 6:26 pm

    People should read their own comments. The river has been appropriated upriver. If the flow was reversed, the U.S. would have invaded.

    Really, read your justifications again.

    Very, very sad.

  8. Adriane
    March 27, 2014, 4:39 pm

    Ross from AU… FYI… Lake Mead/the Hoover Dam is after the grand canyon… Glen Canyon Dam/Lake Powel is before, therefore the water that flows through the Grand Canyon does NOT come from the Hoover Dam. Just clarifying.

  9. El Heffe
    March 27, 2014, 3:08 pm

    The hoover dam provides much of the power used by Las Vegas and other location in the southwest. A major reason for the damming of the Colorado River was to control flooding that happened often. Electricity and fresh water has enabled the parched desert of the American Southwest to flourish.

  10. elishevasmom
    Providence, RI
    March 27, 2014, 2:30 pm

    A similar thing is happening in Spirit Lake by Mt. St. Helens. After the eruption in 1980, all life on land and in the water was totally obliterated. Now, the lake is re-populating more and more, as the original flora and fauna as well.

  11. John Goetten
    Campo Munoz, Rio Hardy
    March 27, 2014, 10:51 am

    When will the pulse flow begin? The current release is clearly only a trickle, 500cfs or less. Downstream flooding is a concern!

  12. Ward Sear
    March 27, 2014, 9:56 am

    There are dry riverbeds all over the Southwest. The Santa Cruz in Arizona, The Mimbres in New Mexico, and countless streams and feeder tributaries who’s water is gone because of rapidly spreading tamarisk plants. No point in demonizing dams in general. Some do lots of good.

  13. Kristen V
    Baltimore, MD, USA
    March 27, 2014, 9:23 am

    This is wonderful news! Great to see it. =)

    Ross in Australia: The purpose of the Hoover Dam was for a few things. Mainly it was built for irrigation (for Southern California and surrounding areas) and to help cease the possibility of flooding in the areas below the dam.

    Right now, the Hoover Dam helps irrigate about 1 million acres in America and 1/2 million in Mexico. It helped those areas be able to have communities and farms where before there wasn’t enough water to sustain that prior to the Dam being built. They also built a power plant into the dam which provides loads of energy (most of it goes to California and Nevada though). Hope this helps! =)

  14. Echo
    March 26, 2014, 10:22 pm

    this is totally awesome news!!!

    isn’t amazing that it hasn’t flowed thru there for 60yrs and yet the vegetation still remembered, and grew as best it could along what use to be the banks of the river!!!

  15. Ross Dorward
    March 26, 2014, 7:19 pm

    We have various rivers like this in Australia–dry because of weather and dry because of damming. The famous Snowy River [of Man from Snowy River fame] has recently been receiving water from the dam and is actually flowing again. thw Murray river hasn’t really flowed into the ocean for years. I’m just so pleased that the Colorado River is making the sea again. I read recently that the Hoover Dam has changed the whole eco-system in the Grand Canyon because any water let out of the dam is from the bottom of the dam and very cold. What is the Hoover Dam used for, one may ask?