Subdivision Improvement Plan Checklist
From Weber County Wiki
- Existing utilities are to be shown on the plans
- A letter from the culinary water provider shall be provided stating that that are satisfied with the design and it meets their requirements.
- Proper clearance from sewer lines shall be provided
- Fire hydrants shall comply with requirements of the Weber County Fire Department.
- Culinary water lateral locations
- Fencing around irrigation ditches
- Land drain systems are to be owned and maintained the the homeowners association or another owner, whom is not the County.
- Developments may have limited basement depths depending on water table level.
- Asphalt thickness shall not be less than 3 inches.
- A minimum of 8” of 4” minus sub-base and 6” road-base.
- Compaction test will be required for the base, sub-base, and any fill.
- Health Department may require pressurized secondary system to prevent flooding of drain field
- Water District may require secondary system to prevent primary usage as irrigation
- Secondary Water lateral locations
- A letter from the sewer district shall be provided stating that that are satisfied with the design and it meets their requirements.
- Gravity flow is always prefered.
- Physical constraints (verify with state rules)
- Check location
- Proximity to waterlines
- Every 400', change in grade, direction
- Four-foot diameter on line
- Five-foot diameter on intersection
- Benching required
- Septic Systems
- Drain fields must be >100' from a drainage ditch and wells unless the ditch is piped with gaskets
- Design: 10 year storm for initial collection and conveyance. 2 hour storm approximately: 0.97 - 1.10 in. Varies throughout the county. Use the NOAA website.
- Detention Facility
- Runoff shall not exceed 0.1 cfs/acre.
- Basin shall have adquate capacity.
- Direct discharge (pipes) into receiving water is not acceptable. Provide some cleaning, i.e. desilting, holding time.
- Sheet flow discharge may be acceptable
- Catch basins must be specified, or catch basin detail must be included
- A Notice of Intent (NOI) is required for coverage under the Utah Pollutant Discharge Elimination System (UPDES) Storm Water General Permit.
- A SWPPP is required prior to obtaining the NOI.
Curb & Gutter, Sidewalk
- Required for all commercial
- Planning can defer these requirements
- All subdivision with less than 1 acre lots require C&G
- Sidewalk is required in the proximity of an Elementary School
- All curve data should be shown for the centerline of the road
- Back of Curb data should be shown, usually at intersections
- Check for proper drainage (no ponding)
- Check for traffic design
- Check max. 8% slope on major streets
- Check max. 12% slope on minor streets
- Check max. 15% slope on private streets
- Check max 4% slope on cul-de-sacs
- Check 4-5% slope at intersections for approximately (2) two car lengths
- Are cut and fill easements required?
- Check driveway designs
- Check that utilities are within ROW
- Cul-de-sacs radii: 55' in upper valley, 50' in lower valley
- Must make provisions to continue existing streets in adjoining areas
- Minor streets approach major streets at angle of not less than 80º.
- Major streets: 86 feet, minor streets: 66 feet
- Private streets: not less than 50 feet
- Minor terminal streets (cul-de-sac): 650' or may serve 14 lots max
- Max. length of 2000' to beginning of turnaround for design
- Check that what is on the Plat is not left off the improvement drawings
- Roads which are proposed to go straight through and are currently more than one lot deep must have a cul-de-sac turnaround
- These are required if and when new utilities tie into existing utilities in the ROW.
- Water, sewer, storm drain, etc.
- Street centerline monuments
- Survey monuments (rebar & cap)
- Developer may want to insist on submitting reproducible for as-builts (see subdivision ordinance).
- The as built improvement plans should be on Mylar and PDF.
- Required for dead-ends, intersections, etc.
- Developer pays for signs & road department installs them