News

Matadero Creek dry-out puzzles residents

Sudden drop in creek levels this summer are unprecedented, some say

For years, Matadero Creek in Palo Alto's Barron Park neighborhood flowed year round. But on June 27, the water level dropped by a foot, with sections of the creek suddenly turning bone dry. Even the birds seemed nervous about the change, nearby residents said.

Creekside Inn Manager Luis Carreno said the disappearing water has economic significance. Visitors who stay at the inn because of its location next to the usually burbling creek were asking what had happened, he said.

Carreno asked the City of Palo Alto and the U.S. Department of Fish and Game to look into the disappearing water, but no one seemed to know what happened.

Residents and experts are speculating about a number of possible causes. For one thing, three earthquake faults run through the area.

"Faults can act as a barrier to the movement of groundwater, and there can be significant differences in groundwater levels across faults," said Vanessa De La Piedra, senior water resources specialist for the Santa Clara Valley Water District.

The faults cause folds in subsurface layers that can channel underground water in different directions.

The cleanup of toxic groundwater could be another factor. Groundwater removal in the area since 1996 has included pumping, cleaning and discharging the clean water into Matadero Creek, according to the state Department of Toxic Substances Control.

Wells extracted 104,180 gallons of water per day beginning in 1996, according to the department. The pumping doubled the water in the creek during the driest months, according to U.S. Geological Survey statistics from 1953 to 2011. In fact, from 1953 to 1963, no water was found in the creek from May through September, the USGS reported.

Because of the discharges, though, the creek levels have risen from their historic levels, said Randi Jorgensen, Department of Toxic Substances Control spokesperson meaning that residents have grown accustomed to an unnatural level of water in the creek.

Could the summer's sudden drop in water have been caused by changes in the cleanup effort?

Brenda Ma, senior project engineer for Arcadis, a contractor working on the water remediation at 3400 Hillview Ave., said the pump there did shut down for a few days due to a malfunction around the end of June. But it was put back on line.

She said the creek's water drop is probably due to the dry winter rather than the pump malfunction.

"The dates don't correspond from the malfunction to when the creek went dry," she said.

Jorgensen said last week that fewer wells are running overall in the cleanup effort, which means less water discharged into the creek.

"As the contamination has reduced, we've needed fewer wells to operate," she said.

Another possibility is that the groundwater pumping removed too much water near and under Matadero Creek. That, said De La Piedra, could cause a drop in both the groundwater table and stream flow if the water is not replenished by rainfall, runoff or water from other tributaries.

Ma also did not think the wells were lowering the underground water table.

"There are so many factors. Our system is relatively small," she said.

Then there are seasonal variables, along with the natural contours of the creek.

A certain stretch of Matadero Creek where Barron Park historian Doug Graham lives "was observed to have a constant, year-around low flow even during drought periods." But starting at the Laguna Avenue bridge, "It was generally dry below that bridge from mid-summer until the winter rains started in earnest."

De La Piedra agreed that water levels in Matadero Creek are variable.

"There are reaches of Matadero Creek that dry out during the summer or drought conditions," she said.

Water still flowed in the neighborhood's Bol Park last week, and it continued to Josina Avenue. But where the creek runs under Matadero Avenue at the Matadero Avenue Bridge, the water stopped abruptly. The creek bed was bone dry.

The likely culprits for now are three extraction pumps that have been shut down for repairs since mid-to-late July, Jorgenson said. Those wells were expected to be running again by the end of the week. But after the pumping is completed, the creek some residents have come to know could look and act differently, she said.

"We don't know if those areas of the creek are dry because they were dry originally during this time of year or if it is because of drought," she said.

Comments

Posted by duh, a resident of Adobe-Meadows
on Aug 16, 2012 at 11:06 am

Global warming = drought = no water in the creek


Posted by qq, a resident of Barron Park
on Aug 16, 2012 at 12:59 pm

This may have to do with the 101 work over Matadero Creek.

The creek east of the bridge is very high due to the tide gate problems described here yesterday. However, at the bridge new pipe is being installed for 101 and a large pump has been installed to drain water into the sewer system.

It can all be seen just north of the MSC on East Bayshore.

Could this also be why the Palo Alto creek monitor has been broken since April 27th?

Web Link

As a backup, NOAA has a new tide station on Coyote Creek. It is producing excellent tidal data for the south bay.

Web Link

qq


Posted by n0s, a resident of Adobe-Meadows
on Aug 16, 2012 at 9:51 pm

the water levels in the baylands seem high too


Posted by Douglas Moran, a resident of Barron Park
on Aug 18, 2012 at 3:31 am

Douglas Moran is a registered user.

FYI: The section of Matadero Creek discussed in this article is above El Camino, and is far, far above tidal influences.

Some additional factors: The development in this segment and above changed how the groundwater that feeds the creek was recharged. First, hardscapes (streets, driveways, roofs, ...) can divert rain water into storm drains, thereby preventing it from being absorbed. On the other hand, traditional landscape watering practices can add to the groundwater, and but this compensation could be lost as people switched to more "water-wise" practices. And ...


Posted by Outside Observer, a resident of another community
on Aug 18, 2012 at 10:39 am

@qq,

Actually, the creek monitor does work:

Web Link

The one linked through "Public Works" works, but the one linked through "Public Safety" doesn't.

Go figure...

Another fine job from City IT


Posted by Doug Graham, a resident of Barron Park
on Aug 18, 2012 at 2:09 pm

QQ Due to the natural slope of the land towards the bay, the creek drops about 50 feet between Laguna Avenue and the 101. Therefore, the 101 work could not have any effect in Barron Park.


Posted by Jessica, a resident of Barron Park
on Aug 27, 2012 at 10:43 am

It's definitely a human controlled issue, not a natural result of global warming, water tables, what have you, as the level behind my house clearly is either "on" or "off." When the water dropped in June, it was very sudden, lasted a few days, then was back to "normal." (Where "normal" is the man-made normal level, not the natural level before human intervention.) There was another drop on August 17. Aug 16 am water levels were normal. I did not check Aug 16 pm. Aug 17 am the creek was empty (though water lines were still visible so the shut off had to have been relatively recent.) Aug 17 pm the water was back "on." This time it wasn't "off" long enough for the egrets to discover that the fish were easy pickings. The June shut-off caused quite a few fish to get stranded in small puddles and more herons and egrets came to visit than usual. But boy did things start smelling ripe after a couple of days. Even though the summer flow is non-natural, the local wildlife (not all native, I'm sure) has come to rely on it.


If you were a member and logged in you could track comments from this story.

Post a comment

Posting an item on Town Square is simple and requires no registration. Just complete this form and hit "submit" and your topic will appear online. Please be respectful and truthful in your postings so Town Square will continue to be a thoughtful gathering place for sharing community information and opinion. All postings are subject to our TERMS OF USE, and may be deleted if deemed inappropriate by our staff.

We prefer that you use your real name, but you may use any "member" name you wish.

Name: *

Select your neighborhood or school community: * Not sure?

Comment: *

Verification code: *
Enter the verification code exactly as shown, using capital and lowercase letters, in the multi-colored box.

*Required Fields

Handmade truffle shop now open in downtown Palo Alto
By Elena Kadvany | 3 comments | 2,323 views

Why is doing nothing so difficult?
By Sally Torbey | 7 comments | 1,064 views

Breastfeeding Tips
By Jessica T | 4 comments | 864 views

Weekly Update
By Cheryl Bac | 0 comments | 723 views

Call it a novel: Dirty Love by Andre Dubus III
By Nick Taylor | 1 comment | 245 views