Subcommittee weighs gravity versus step (pumped) systems and lift‑station tradeoffs

Members discussed two broad conveyance strategies: a gravity system that could run from Los Olivos to Solvang if the county allows a pipeline to be hung from bridges, or a step (pumped) system that uses small pressure mains and private on‑site effluent tanks. Carrie said the draft assumed private owners would bear step‑system component installation costs and that the district would hold access easements, but she acknowledged easement acquisition and legal costs were not yet included in the draft.

The group noted that a gravity main would require larger pipe diameters (10–12 inches was discussed) and could eliminate at least one lift station but increase trenching depth and construction cost, while a force main for a step system would likely use smaller diameter pressurized pipe (6–8 inches). Carrie said she ran both sets of numbers and found the life‑cycle costs to be within a reasonable range so far, and that no clear winner emerged at the 30% level. “If we are capable of doing a gravity system…this again goes back to do we need equalization storage or do we not? Because if we don't need equalization storage, we can eliminate the Santa Barbara Lift Station,” she said.

Board members asked Wallace Group to refine pipe‑size callouts and clarify where diameters apply to collection versus transmission systems, and to include easement‑related legal costs in the next draft. No final system choice was made; the subcommittee left the decision pending further coordination with Solvang and the county.