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Searching for a better dig for Hahamongna: Larry Wilson





<b>October 31, 2017</b> - Larry Wilson urges Supervisor Barger to "ask county staff to ratchet down the Big Dig into the Appropriately Scaled Dig, and then asks her colleagues on the Board of Supervisors to approve a new version of the plan to save Hahamongna and all that lives downstream."


Larry Wilson


Pasadena Star-News


The Devil’s Gate reservoir basin including the Devil’s Gate Dam and Hahamonga Watershed Natural Park in Pasadena, Monday, Sept. 14, 2009. SGVN/Staff photo by Eric Reed/SVCITY

The rainy season, such as it is, in Southern California will soon be upon us. Why, it even sprinkled overnight the last two evenings at our house here in town.

What kind of rainy season, drenching or droughting? I love the answer everyone’s favorite climatologist, JPL’s Bill Patzert, acknowledging there is no El Niño wet pattern in sight, gave to colleague Steve Scauzillo in September: It’s going to be either wet or dry.

He cited the National Oceanic and Atmospheric Administration saying that from our perspective here in autumn, December-January-February in California will be a winter with equal chances of normal, below normal and above normal rain.

“That means they do not know. There is no strong signal,” Bill told Steve.

So even the guys in the know do not know if nature is going to be keeping our lawns green or just allowing the xeriscaping to survive, if our reservoirs are going to be on the down-low or if our aging dams are going to be pushed to their limits.

But, talking of dams, one thing we do know is that the ongoing argument about what to do with the tons of sediment that have built up behind Devil’s Gate at Hahamongna in the Upper Arroyo Seco will still be raging like Niagara.

No one involved argues that doing nothing is the best policy. After decades of allowing the mud and boulders to pile up behind the oldest flood-control dam in the region, abetted by extra debris washing down from the San Gabriels after the devastating Station Fire, Los Angeles County Public Works has to do something in order to protect all who are downstream: Brookside Golf Course, the Rose Bowl, Busch Gardens, the Pasadena Freeway and South Pasadena.

There’s just a strong difference of opinion about how much muck to truck out over how long a period of time spending however much taxpayer money. County Public Works Director Mark Pestrella and his team have a plan to remove 2.4 million cubic yards over several years at a cost of up to $100 million. A group of community activists from Altadena, La Canada Flintridge and Pasadena, along with the city of Pasadena and our editorial board, including me, call that scheme the Big Dig. After the years of doing too little, it’s doing too much, at too much expense and upheaval. We’re in favor of taking out more like 1.1 million cubic yards, which we believe would be equally safe and far less disruptive both to the neighborhoods and to the gorgeous watershed park that Hahamongna has become.

But we’re not the deciders. That would be the county Board of Supervisors, which is scheduled to vote on the matter Nov. 7.

Very much to her credit, new Supervisor Kathryn Barger, at the behest of Pasadena activist Christle Balvin, gathered a group of us at her Pasadena office Monday afternoon to talk about Devil’s Gate. Among those attending were Pasadena Mayor Terry Tornek, Altadena Town Council member Dorothy Wong, Don Bremner of the Sierra Club, La Canadan Toni Bird and Tim Brick of the Arroyo Seco Foundation, which has litigated against Public Works in opposing the plan.

But the county’s Pestrella was there to prevent his case, and Barger was clear that this was not a formal mitigation meeting, but a chance to talk.

And talk we did. Listening, it was clear that there was no definitive right or wrong plan here — just a need to do something before the rains. Though Pestrella is strong in his beliefs that the right way forward is to remove the larger amount of debris, taking many acres down to bare dirt by removing much alluvial scrub habitat, the rest of us wanted to take it easier.

Mayor Tornek eloquently lobbied Supervisor Barger for the smaller dig, noting that Pasadena recommends taking out 220,000 truckloads of dirt a year vs. a massive 800,000 truckloads annually under the county proposal.

“Our concern also has been public safety,” said Brick. “And we think our position, the Pasadena plan, is equally or even more protective of public safety.”

I think so, too, and hope that Barger asks county staff to ratchet down the Big Dig into the Appropriately Scaled Dig, and then asks her colleagues on the Board of Supervisors to approve a new version of the plan to save Hahamongna and all that lives downstream.

Larry Wilson is on the Southern California News Group editorial board. Twitter: @publiceditor.




Arroyo Seco Foundation, PO Box 91622, Pasadena, CA 91109-1622 (323) 405-7326