While many of us have had to return to more mundane lives, Jennifer Pitt remains in the Colorado River delta, documenting the environmental “pulse flow” as it makes its way toward the ocean. The water’s been slowing as it crosses dry stretches where depth to groundwater is great and dry sand soaks up a big share, and moving more quickly across the stretches where water tables are high, mostly due to nearby irrigated agriculture. Where the Colorado River once spread in sheets of flooding across this delta, now we do some of the same thing with water in irrigation canals. Here’s Pitt:

Now that the dry reach has been saturated, we expect water to move more speedily. The leading edge of the pulse flow will now travel the middle and lower reaches of the delta, reaches that are typically wet due to high groundwater and drainage from nearby agricultural fields. Infiltration will not be nearly as great, and the water should run rather than creep. The pulse flow still has miles to go, but these miles should be easier to travel.

Will the pulse flow reconnect the Colorado River to the sea? We still don’t know. We don’t even know that we’ll be able to see it when it does. But scientists will be out there taking conductivity measurements, and will tell us if, and when, water at the river’s mouth becomes less salty as freshwater arrives.

Pitt posted a nice map from the U.S. Bureau of Reclamation documenting the water’s progress:

Pulse Flow progress, courtesy USBR

Fingers of water creeping down a Colorado River side channel, pulse flow, March 25 2014, by John Fleck

In High Country News, Matt Jenkins on  the Colorado River delta environmental “pulse flow”, which grew out of “Minute 319”, an addendum to the U.S.-Mexico water treaty:

Over the past two decades, the Delta’s advocates have argued their case with perseverance, and a lot of good numbers. By monitoring the effect of the pulse flow, they’re hoping to make the case for a followup agreement — a Minute 320 — to kick off a long-term program of regular floods that mimic the natural dynamics of the river.

pulse flow in a dry riverbed, near San Luis, March 25, 2014, by John Fleck

Folks working on the current Colorado River “pulse flow” must fight against the deeply held perception that the river in Mexico’s Colorado River delta is “dead.” Blame Phillip Fradkin, whose 1981 book “River No More” is one of those touchstones in the regional literature that dominates public understanding, even if it isn’t quite right. Writing in the Journal of Arid Environments in a 2001 special issue on the potential for delta restoration, Mike Cohen of the Pacific Institute wrote this:

[D]espite reports that the delta was a dead ecosystem where the Colorado River no longer reached the sea (Fradkin, 1981), agricultural drainage and the occasional space-building releases of Colorado River water from upstream reservoirs have prompted significant new growth of valuable native riparian and emergent wetland habitat, sup- porting the largest and most critical arid wetland in North America and sustaining avian and aquatic species of concern (Glenn et al., 1992, 1996; Luecke et al., 1999). Flood releases have also been strongly correlated with a rise in the shrimp catch in the Upper Gulf (Galindo-Bect et al., 2000), an indication of the renewed viability of an important estuary.

The Fradkin meme has made the political side of restoration efforts harder, because of the perception that the delta had already been lost. In fact, those ag return flows and high water tables from irrigation have kept some stretches within the levees through the Mexican delta wet. Jennifer Pitt of the Environmental Defense Fund makes that point in a post yesterday documenting her pulse flow river-chasing adventures:

These releases – lasting eight weeks – are being made from Morelos Dam, about 100 miles (160 kilometers) upstream from the river’s end at the Upper Gulf of California (Sea of Cortez). About 75 of those river miles (120 kilometers) are typically wet, either from a high groundwater table or the tides that make their way upstream. But a reach of about 25 miles of the channel have been dry for decades, hot sand baking in the desert sun.

Be sure to check out Pitt’s fun videos, where she seems to have strapped on a GoPro while tromping through the delta. Here’s a picture I took when I bumped into Jennifer, Mike and friends last week at the endless river party at San Luis Río Colorado, grinning. Really, a lot of grinning was involved in this whole thing.

Jennifer Pitt, left, Mike Cohen (sunglasses, wading in the river) and friends on the Colorado River at San Luis, March 2014, by John Fleck

Ricardo Castillo celebrates the Colorado River “pulse flow” and reminds of us the transboundary tensions that preceded it. He sounds pissed:

U.S. Americans proudly boast about the beauty of the Grand Canyon and the might of the Colorado River as “great American treasures.”

Over the past 50 years, however, both the U.S. federal government and the governments in the water hoarding states of Colorado, Utah, Nevada, Arizona and California forgot one little detail. The Colorado River does not stop at the U.S.-Mexico border but flows into the Gulf of California.

So by the time Mexico gets its share of water — which should be on equal terms with the aforementioned states — reality has it that a trickle-down policy has been applied.

The end result has been that the Colorado River Delta, which is in Mexico, has dried up.

The good news is that at long last, U.S. Americans have stopped playing deaf and dumb on this issue and finally agreed to allow the spring pulse flow into the delta. It may not be much as it is — barely 1 percent of the total Colorado River water — but scientists coincide that it will be enough to bring the delta back to life.

More than once last week while I was down in the Colorado River delta, I heard people involved with the historic “pulse flow” talk about one of the problems that comes next: managing expectations.

Fox Latino calls it a “flood”

This headline and file art, from Fox Latino, illustrates the problem. “Colorado River Begins Flooding Dried Up Delta,” the headline reads, accompanied by a picture of the Colorado River near Page, Arizona. The Colorado River I watched last week flowing past San Luis Río Colorado in Sonora, Mexico, was a beautiful thing to see, but it was another thing entirely from the stock imagery you see here.

I don’t recognize where the picture accompanying the Fox Latino story was taken, but the Colorado River at Lee’s Ferry (the nearest gage to Page) is running right now with a peak flow of around 10,000 cubic feet per second (a little less than 300 cubic meters per second). On Friday at San Luis, the last good number I had from a member of the U.S. Geological Survey team working on the pulse flow monitoring was around 1,300 cfs (37 cms). The releases from Morelos Dam, the place where water is being turned loose into the normally dry delta channels, are larger, but it’s a parched system, and the losses as the water headed downstream were significant.

USGS monitoring on the pulse flow, March 28, 2014, by John Fleck

In the desert landscape, it looked like a substantial river, as the picture to the left shows, but nothing like the “Mighty Colorado” imagery conjured up by a Fox Latino desk editor looking to fill a click-bait slide show.

In San Luis Río Colorado, the party was genuine, but it wasn’t clear how much the partiers understood how short-term this flowing river was going to be. That, at least, was the worry. I talked to four twenty-something men under the bridge in one of those broken Spanglish exchanges who clearly had little idea why the water was there or how long it would last, only that it was wonderful. “Thank you Americans!” one of them said. Our shared language wasn’t up to the task of communicating the fact that it was Mexican water, and the Mexican government and non-governmental organizations who were equally responsible for this shared project.

Here’s the thing. Wonderful as it is, the water is not going flow through San Luis for very long. The peak releases from Morelos Dam end today (Sunday, March 30). The releases will decline rapidly after that, with releases from Morelos into the main river channel ending completely by the third week of April, according to the USGS. It’s truly a “pulse” of relatively high water moving down the channel of relatively short duration, not a sustained simulation of a full spring flood flow. For the rest of April and into May, water for environmental flows will continue, but instead of being released into the main channel, the water will be moved through Canal Reforma and Canal Barrote, bypassing reaches of the river where infiltration losses were expected to be substantial because of deep water table.

Scientists and journalists tour Laguna Cori restoration site in the Mexican Colorado River Delta, which awaits its first flows. March 27, 2014, by John Fleck

That will allow water to be targeted directly to key habitat restoration areas like this one at Laguna Cori, on the river’s western bank, which I toured with some members of the project science team and a group of reporters Thursday. (Huge thanks to Karl Flessa from the University of Arizona for shepherding around the delta.) Within the next couple of days, the scientists expect the main pulse released from Morelos, after having travelled down the main channel, to reach the key habitat restoration areas. The idea is a wetting from the channel to coincide with cottonwood germination. With the rapid recession in main channel flow, water then will be moved via more efficient irrigation canals to keep the site wet into May. This a site with a very shallow water table, which offers a much better chance for restoration. Properly nurtured, the scientists hope, the cottonwoods will be able to get their roots down into the water table, giving them a shot over the long run.

I admit to being as caught up as anyone in the “living river” part of this. Watching the water fill the dry, sandy Río Colorado bed at San Luis, watching the happy scientists and happy townsfolk splashing and partying was special. But if a “living river” is the goal, this is a very modest first step. Incredibly important, historic even, but modest.

Expectations are a funny thing.

Water flowing downstream, below Morelos Dam, March 27, 2014

Packing up this morning to head home after a week watching the environmental pulse flow on the Colorado River into Mexico. Ran across this in one of my notebooks, from Bob Snow, an attorney in the U.S. Interior Solicitor’s Office who has been working on this since the ’90s and helped negotiated the international agreement that enabled this to happen. We were standing on the dam, watching the water flow south:

I think this is the most beautiful sight I have seen in my career.

To be fair, Bob is the kind of guy who grins a lot anyway. But this week, the grin seemed bigger.

John Fleck, standing in the bed of the Colorado River north of the San Luis Bridge, looking upstream at the advancing water, March 25, 2014. Juan Hernandez took this picture.

I consider it a great accomplishment that I spent an entire week in the desert sun of the Colorado River delta without getting sunburned.