Deschutes County Environmental Soils recommends having a licensed Department of Environmental Quality installer or designer submit the system details. Include all proposed items in plot plan. Doing so initially may save the cost of doing revised plot plans and added fees in the future. In addition, check with the field sanitarian for your area to see if there are special standards. For example, there are special standards that apply to southern Deschutes County for new construction, major alterations, and major repairs.
Materials required for all systems:
- Four copies of scaled plot plan on at least 8 ½ x 11 inch sheets of paper. Parcels larger than two acres should include a detailed blow up of areas where septic system components are located. Only two copies of septic system details are needed.
- Property description and all property dimensions.
- Arrow indicating north.
- Directions and percentage of slopes within installation area.
- Location of test holes used for approved site evaluation
- Location and dimensions of all septic components (tanks, transport lines, distribution valves and boxes, treatment units, drainlines, cleanout valves, monitoring ports, and reserve drainlines.)
- Distances of septic components from each other including spacing between drainlines.
- Elevations of the native soil surface at septic tank and both ends and middle of all drainfield trenches. In the reserve area, four outline elevations will suffice.
- Location and distances from septic components to all the following:
- Water ways - lakes, rivers, streams, ponds, canals and ditches, springs.
- Wells and waterlines (both irrigation and potable)
- Property lines and easements
- Utility lines (underground and overhead)
- All structures
- Escarpments, man made cuts and fills
For pressure distribution systems and sand filters include:
- Hydraulic Calculations determining total dynamic head and net discharge in gallons per minute.
- The pump model and pump curve
- Type of control and float system to be used.
- Length, diameter and location of discharge assembly, transport line, manifold, and distribution laterals
- Orifice spacing
- Comparative elevations of low water level in tank and distribution laterals to determine use of anti-siphon valve.
- Septic tank(s) capacity, model and manufacturer.
- An electrical permit.
For sand filters also include:
- Type of container used, concrete or plywood. Concrete container proposals require engineered plans from a licensed professional engineer.
- Overhead drawing of sand filter distribution layout. Include transport pipe, manifold, lateral, orifice, and cleanout locations.
- For lined sand filters include side view and relative elevations of liner, collection pipe, outlet pipe and distribution pipe at trench.
- For bottomless sand filters on slopes of greater than 3%, a side view showing native slope and how much countersink will take place to make base of sand filter level.
- A cross sectional drawing of the container showing the layering of materials.