Feature Story

UNIQUE SAN DIEGO COMMUNITY RELATIONS PROGRAM PAVES THE WAY FOR SUCCESSFUL SEWER MAIN RELOCATION PROJECTS

PROJECT BACKGROUND

The City of San Diego, California has approved the construction of an aggressive $1 billion 10-year capital improvement program to address deficiencies in the municipal sewer system. Many of the City's sewer mains are located in canyons, between property lines or under buildings. Scores of these private sewer laterals need to be rerouted from the old sewer mains to the new sewer mains. The rerouting of these private sewer laterals is known as "replumbing."

Each replumbing project requires contacting residents and property owners in older neighborhoods to schedule, coordinate and gain concurrence with the proposed replumbing routes, including landscape and hardscape replacement.

In two neighborhoods, Chelsea Street and Cottontail, the City of San Diego, in partnership with Berryman & Henigar, initiated an extensive one-on-one public outreach program to facilitate design and schedule of the sewer main relocation. To gain concurrence for the replumbs in each neighborhood, the public outreach program was crucial to project scheduling. Recognizing this, the City made the crucial decision to make the replumbs and homeowner concurrence a top priority in both neighborhoods as part of the design effort.

NEIGHBORHOOD CHALLENGES

The two affected neighborhoods, Cottontail and Chelsea Street, each posed unique engineering challenges. There had been sewer main breaks and blockage in recent months in the Cottontail area, and because the sewer mains were located in a canyon, fixing the breaks presented unusual challenges. In addition, submersible pumps were potentially needed for some residences due to the low elevation of the private sewer lateral. The City considered pumps to avoid making the sewer main too deep to maintain for one or two homes. Additional challenges encountered were that many homes were constructed on excessively steep slopes (25 percent or greater) and needed to maintain a sewer main depth above 30 feet.

Chelsea Street had been experiencing a lot of sewage backup and there were frequent odors. The geotechnical findings showed that the cobble and boulder (rocks and boulders in excess of 8 inches up to 36 inches) content in surrounding soils was over 50 percent, which precluded the use of microtunneling for the private sewer laterals and a large portion of the 21-inch diameter sewer main. Microtunneling machines are generally incapable of handling the percentage and diameter of rock anticipated on this site.

WORKING WITH RESIDENTS

Before the City began the replumb projects, a public outreach program was implemented. Letters were sent to all residents/property owners inviting them to attend meetings sponsored by the City. In the event they were unable to attend, mailers were also provided giving detailed information on why the City was initiating the program.

Local community groups such as the La Jolla Planning Association and Bird Rock Association were contacted as well. Each resident/property owner received an average of three to five phone calls from the City and Berryman & Henigar design staff. The project staff canvassed the neighborhoods weekdays (with appointments), evenings after 5 p.m. during the week and on weekends between 10 a.m. and 2 p.m., to talk at length with those residents who wanted to speak to someone face-to-face.

Each property owner was also asked to sign a replumb agreement that succinctly spelled out the work that was going to be conducted on the property. It also guaranteed the work for one year.

Prior to beginning the replumb project, a 12-point task list was conducted, consisting of the following elements:

Notify homeowner
Notify on-site resident
Videotape pre-construction conditions
Assess pre-construction functionality of irrigation system
Assess pre-construction functionality of drainage system
Chalk mark-out replumb alignment
Tag all landscape material to be affected
Review impact area with homeowner
Confirm landscape replacement with homeowner
Verify secondary laterals upstream of connection point
Vertical verification of existing sewer
Assess crawlspace alternative alignments

City staff, including engineers, the Public Information Officer, and Berryman & Henigar engineers worked closely with property owners and residents to make certain that each individual concern, such as noise, maintenance/replacement costs, and repair was adequately addressed.

Tasks included conducting a series of presentations for community associations, frequent mailers, telephone contact with each property owner, follow-up telephone calls, providing FAQs to residents upon request, and collaborating with property owners to ensure that their particular "replumb" project went smoothly. Key to gaining the residents' confidence was providing instant accessibility to a person who could respond to each resident's concerns.

TECHNICAL REQUIREMENTS

The successful concurrence with property owners on the proposed replumb alignment (the new route to connect the private sewer lateral to the new sewer main) hinged on adequate preliminary technical findings. These technical findings are described as follows:

A preliminary geotechnical investigation was conducted. These findings dictate what types of construction methods can be undertaken in conjunction with space constraints (hand digging, conventional trenching, or directional drilling and/or microtunneling);
A survey was then conducted, which consisted of taking an aerial photo with one-foot contours (the survey must go all the way to the back of the lot);
Determination of the legal lot boundaries. A City standard requires one sewer lateral per legal lot;
Location of the horizontal and vertical alignment (depth) of each private sewer lateral. In neighborhoods built in the 1940s this is not an easy task! Record drawings, extensive field surveys of each property, and use of state-of-the-art CCTV/electronic sensors were used in combination with property owner anecdotes;
Secondary lateral connection points (guest houses, laundries, garage) were also identified;
Accurate identification of landscape and hardscape that will need to be replaced. The City used a landscape architect to determine salvage and replacement needs for each property.

The connection must stay on the legal lot and cleanout locations were made every 100 feet and/or at all bends. The maximum allowable bend is 45 degrees with a minimum slope of two percent. All of the technical requirements dictated multiple site visits with each resident and an excellent partnership with the project staff. Once the technical requirements had been determined, a replumb connection was identified from the existing sewer lateral to the new sewer main, and a map of the proposed route and property restoration was sent to the property owner along with an agreement.

CAPSULE SUCCESS STORIES

Each replumbing project cost the City between $15,000-20,000 (no charge to residents/property owners) and took an average of 40 hours to complete. Each replumbing was also unique. Some snapshots:

Joe La Cava

Joe La Cava's 2,200 square-foot stucco house in the Bird Rock area of San Diego was built in 1950 and was recently remodeled. La Cava is a land development consultant and a registered civil engineer. His home is about 200 feet from the beach.

"We had been experiencing odors for the past few years and there was an ongoing neighborhood debate if it was the sewer line or kelp," La Cava said. "So it was fortuitous when the City notified us that they were going to replace the sewer lateral."

Fortunately for La Cava, he was in the midst of a major remodel when approached by the City.

"The City accelerated replumbing the sewer lateral at our house because of the remodel," he said. "We were able to completely replumb the house-City engineers worked with us to extend the sewer lateral underneath the house so it could be connected to the new plumbing."

La Cava added that one of the major challenges the City faced was a 50-year old yucca plant in the front yard.

"The root system was enormous and to complicate matters, the gas line ran right through the middle of it," he said. "We decided to remove the yucca plant, which involved removing and replacing some of the concrete. Even with these obstacles, the work went smoothly."

Jennifer Roach

The Roach residence is in the Chelsea Street neighborhood. The single-family house, built in 1939, has an 80' x 30' backyard.

"With three kids and a major guest house addition in the works, I didn't have a lot of time to deal with sewer issues," she said. "I didn't attend any of the community meetings, but the materials supplied by the City were very thorough so we knew exactly what they intended to do."

Two small trees in the backyard had to be removed to accommodate the sewer lateral changes.

"Fortunately our house was a relatively easy one for the City-no concrete to dig up, no major landscaping that had to be uprooted," she said. "We were very pleased with the results."

William Tice

The Tice residence is just a few doors down from the Roach home. The home was constructed in 1950. When the City notified Tice that they needed to replumb his property, he was initially concerned.

"We had just painted the house and have an extremely narrow space along the side that was going to be affected," he said. "They also indicated they were going to have to tear up our driveway, too."

Over a four-week period, the City moved the sewer line from the 50' x 25' backyard to under the street where it would be more accessible. Tice paid the contractor "a bit extra" for additional improvements that included widening the sidewalk on the side of the house and the driveway.

"I saved a lot of money doing this and the City came out ahead because they can handle sewer-related emergencies in our area more effectively now."

CONCLUSION

By launching an effective communications program, the City was able to quickly handle any concerns that residents and property owners had prior to beginning the replumb projects. Roles and responsibilities were clearly defined and a standardized replumb process was initiated which expedited scheduling and defined construction alternatives that kept the projects within the pre-established budget.

The net result is that this public/private sector partnership will now enable the City to more cost-effectively maintain and repair the sewer mains in these neighborhoods. The City also plans to expand the replumb program to other areas in the near future.

Return to: 2002 Feature Stories