. EXAMPLES FROM THE DEMONSTRATION PROJECTS

The city of Lacey requires a 10-foot separation between public water and public sewer, a state and local code provision. When a sewer lateral crosses a water main or vice-versa, a З-foot vertical separation must be maintained. This occurred in The Park, but Phillips was unable to make the З-foot vertical separation.

Because of this, the city required a heavy gauge metal sleeve around the water pipe within 10 feet of the sewer. This apparently is a carryover requirement from the time of cast iron and concrete soil pipe, when joints often broke and leaked. However, with longer lengths of seamless PVC pipe available, the separation require­ments and the need for a metal sleeve appear to be unnecessary.

Builders in Portland frequently install gas, electric, telephone, and TV lines in a common trench. In addition to allowing this practice, the city of Portland permitted Robinson to install his common trench and water line trench outside the right-of-way. The city also allowed the use of less expensive native backfill instead of off-site granular backfill. The city would not waive their normal require­ment that sanitary sewer mains be placed in a separate trench in the right-of-way. Robinson saved $5,040 by installing his common trench and water line trench outside the right-of – way and using backfill from the site.

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