by Bill Burkhardt
(November 1997)
[Editor's note: Bill writes: Can this be the only unclassified article I've written in an engineering career? Yup. Is it of general interest? Nope. But I mentioned it earlier, so here it is. I say Bill's article is a gripping tale well worth reading, and I will read it myself before too long. Actually there are four articles, and this is the first.]
Dean Allison explained that while RPV owns the sewer system in the city, the city Public Works Department is only staffed by 8 people, not early enough for a major project such as the new sewer in addition to their other duties. For that reason they contract out the project work to Los Angeles County Public Works.
Steve Shar, the spokesman for L. A. County Public works, stepped forward to explain the sewer project things that are likely to impact El Prado residents in the immediate future. He anticipated construction related questions about:
A member of the audience asked about the completion date. It is planned to be the middle of January or perhaps the end.
The digging will commence at Rue de Charlene where the new sewer will connect. Areas along the route that have been designated as "protected" because of archaeological interest (Native Americans) or native vegetation/wild life will be protected by fences. The new section of orange fence, which you may have seen already, on the south side of the maintenance road is the beginning of that effort. The method of installing the new 24 inch diameter sewer pipe has been changed from the technique outlined three years ago. At that time they had planned to dig a trench with 45 degree walls. That would have cause major surface disruption. The less intrusive method now envisioned is "jacking," a way of pushing the pipe through the ground between regularly spaced "jacking pits." Of the 1800 feet of new sewer pipe, 1000 feet will be installed by jacking. The jacking pits will measure fifteen feet by fifteen feet by twenty feet deep. The contractor will dig the pits at regular intervals along the sewer route and 24 inch pipe sections will be forced through the "soil" with hydraulic jacks. Initial soil coring along the route showed rock that would prohibit jacking, so regular trenching will be used there. The pipe will be jacked under the protected sites.
The depth of the pipe will vary from 18 to 31 feet.
With regard to what noise is expected, the jacking processes is relatively quiet. Most noise will result from digging the jacking pits and the unavoidable trenching. The work day is expected to be 7:00 a.m. to 3:30 p.m. (or 4:00 p.m. if the schedule would slip otherwise).
The contractor is responsible for securing the pits and other construction hazards. Los Angeles County Public Works will continually check up on their security measurers.
The Los Angeles Public Works Department will distribute flyers with the schedule of activities when the beginning of construction is imminent.