I was heartened to see articles in the local papers this week about the Devil’s Gate sediment removal project. Despite the massive size of this county public works project, it has received very little publicity. Given the unpalatable nature of the news, however, that is perhaps not surprising: 50 double dump trucks an hour leaving Hahamongna and going by the high school playing fields 12 hours a day, six days a week, nine months a year, for up to five years.
The key question is whether the goals of the project, especially flood protection, could be accomplished by a smaller project with less devastating environmental impacts. The county’s own documents suggest this is the case. When Flood Control first proposed the project in 2010, the plan was to clear 50 acres initially and to leave only 15 acres permanently bare. Now the proposed plan would permanently denude 120 acres from the dam to the JPL campus.
The county received $28 million from the California Department of Water Resources to help fund this project. The state was told the project would remove at most 2,000,000 cubic yards of sediment. Now the project would remove 2,900,000 cubic yards, almost one million cubic yards more. The proposed alternatives range from 2,400,000 up to 4,000,000 cubic yards. If the grant funds were secured for a smaller project, why isn’t that the project studied in the Environmental Impact Report?
In the mid-1970s, there were 3,900,000 cubic yards of sediment in storage in the basin, the same amount as now. Back then, the county removed only 750,000 cubic yards, a project one-third the size of what is proposed now. The question our community should be asking is why this massively larger project is necessary when it will pollute the air with diesel fumes and ash, snarl traffic, disrupt neighborhoods, and destroy rare riparian habitat.
If you would like to see a smaller, more environmentally sustainable project alternative, you can send a comment by Jan. 6 to firstname.lastname@example.org. Let Supervisor Mike Antonovich know about your concerns as well at email@example.com. There is good background information on the Arroyo Seco Foundation’s website, Savehahamongna.org.
Mary E. Barrie
La Cañada Flintridge