- Large rocks were found in the soil, which were not revealed by the initial soil samples. These had to be broken up so they could be removed by the excavating equipment.
- The presence of unrecorded electrical lines under the street which had to be avoided or relocated.
- A revision to the design of the forms for pouring the eastern wall of the chamber, which lies right on the boundary of Western Ave.
- Coordination with other agencies for the diversion of traffic on Western Ave. to allow excavation for the main chamber and the new tie-in into the sewer line.
Sunday, September 06, 2009
The Western Avenue Pumping Station-An Article
The Los Angeles County Sanitation Districts has been working on its pumping station near the corner of Western Avenue and Avenida Aprenda for what seem like forever.
In the latest issue of "The Rolling Stones", the newsletter for the Rolling Hills Rivera and Palo de Encino neighborhoods, there is an article I will post below.
The article was written by Mr. Jim O'Donnell and Mr. Marc Fortain wrote about their visit inside to and inside the pumping station.
I don't think I can publish copies of the photos from the newsletter, but I may try and get a copy of the originals, scan them, and post them. They are remarkable.
Western Avenue Pumping Plant
By Jim O'Donnell & Marc Fortain
Walter Ackerman and John Joyce, Resident Engineers with the LA County Sanitation Districts gave us a tour of the construction site, in late July. They were cooperative and answered all our questions about the project.
The purpose of this plant is to pump the sewage from our area uphill along Western Ave. to Palos Verdes Drive North, where it flows by gravity down to the main treatment plant alongside the Harbor Freeway in Carson.
Construction was begun in August, 2006 to replace the original plant which has been there since 1960. The old plant is nearing its capacity and has equipment that is outmoded and can no longer be properly maintained. The new plant will have adequate capacity for growth and more sophisticated electrical controls.
The new plant consists of four underground rooms: a full-depth (35') wet well to receive sewage and act as a surge tank; alongside it, a lower chamber, housing 3 large and 2 small pumps; an upper chamber for the electric power controls; and the old plant, reconfigured to house a smaller surge tank and an auxiliary diesel generator.
Construction and equipment installation in the first three cambers is almost complete and due to be functionally tested in a few weeks. If it passe it acceptance tests, flow will be diverted from the old plant and the new one will go into service. Conversion of the old plant to the auxiliary area will then require another 5-6 months. All construction work, landscape restoration and site cleanup is expected to be finished early next year.
Since the entire project will have taken more than 2 years longer than originally estimated, we asked for the reasons for the delay. In their opinion, the principal factors for the delay were:
Now for some more information.
What has all this to do with Ponte Vista at San Pedro? Really not a whole lot of anything.
Sewage from the Ponte Vista site, no matter what is built there will flow to the City of Los Angeles Sewage Treatment Plant on Terminal Island.
There is another Outfall System in our future, our closer-than-you-may-think future.
The new plant discussed in the article still will use the Outfall System or large pipes in the tunnel that dates back to about 1957.
The new Outfall System is being considered and studied because the two existing tunnels/pipes are at or near capacity and the third Outfall System is coming to provide relief to the existing systems.
The Draft Environmental Impact Report for the new Outfall System was originally announced to have its publishing and distribution date this fall.
What will really matter to the discussions related to Ponte Vista is where the new Outfall System and its access points will be located. Several of the sites in the Initial Study allowed for the new tunnel to run closer to the existing structures under or near Western Avenue.
The massive 200 foot wide, up to 500 foot deep access pit required to place tunneling equipment underground and to remove earth to dig the tunnel will "HOPEFULLY" be placed at the old LAXT facility on Terminal Island. This would avoid problems placing that giant hole in a residential area.
It is also hoped that the new tunnel will not be dug anywhere near Western Ave. and be placed in a straighter line from the Treatment Plant in Carson and the Pacific Ocean.
A problem with that placement is the possibility of needing to deal with a large number of wells that have been drilled in Carson and Wilmington over the decades.
I was about 5 year's old when we got connected to the sewer system and got to see and help fill in the old septic tank that was right outside our kitchen window.
When one is five, one does not tend to ponder where one's poop goes and to think it only went as far as our backyard was fascinating. Watching the workers dig up Trudie Drive for the big sewer line was interesting and watching how our home's new line past the cesspool and out to the street was dug and placed was downright fun for me, as I remember the bits and pieces.
The article indicates when the estimated completion could occur. I don't think it is wise for anyone to bet on it or any date close to it. The article also included reasons for unexpected delays and I don't feel comfortable that the rest of the project will run completely expectantly.
Four chambers in a pit dug 35 feet deep, right near the corner is something.