Section 58.01.16.411 - FACILITY AND DESIGN STANDARDS FOR MUNICIPAL WASTEWATER TREATMENT OR DISPOSAL FACILITIES: PRELIMINARY ENGINEERING REPORTS01.Preliminary Engineering Reports Required. Preliminary engineering reports are required for municipal wastewater treatment or disposal facility projects that require plan and specification review and approval pursuant to Subsection 400.03 and shall address all applicable issues specifically required in Sections 411 through 599 of these rules including, but not limited to, purpose, scope, hydraulic capacity, treatment capacity, and operation and maintenance considerations sufficiently to determine the effects of the project on the overall wastewater infrastructure. Preliminary engineering reports must be completed for major wastewater collection system projects, all pump station projects, all treatment plant designs and upgrades, and all septage transfer stations. Preliminary engineering reports are not required for simple wastewater main extensions that are approved in accordance with Subsections 410.01.a. or 410.01.b.02.Submittal to Reviewing Authority. Preliminary engineering reports shall be submitted to the Department for review and must be approved by the Department prior to the submission of plans and specifications.03.Preliminary Engineering Report Contents. The preliminary engineering report must include sufficient detail to demonstrate that the proposed project meets applicable criteria. The preliminary engineering report generally addresses project specific issues rather than the overall system-wide plan. The preliminary engineering report shall identify and evaluate wastewater related problems; assemble basic information; present criteria and assumptions; examine alternative solutions with preliminary layouts and cost estimates; offer a conclusion with a proposed project; and outline official actions and procedures to implement the project. The items included in Subsections 411.03.a. through 411.03.c., and other items specifically called for in Sections 426 through 599, shall be addressed in detail in the preliminary engineering report. If specific items are not applicable to a particular design, then the designer shall state this in the preliminary engineering report and state the reason why it is not applicable. Items adequately addressed in the facility plan under which the project is being designed, may be addressed by reference for purposes of the preliminary engineering report.a. Major Wastewater Collection System Projects. Items applicable to preliminary engineering reports for major wastewater collection system projects are listed in Subsections 411.03.a.i. through 411.03.a.vi.i. Coordination with Facility Plan. The preliminary engineering report shall discuss or reference items provided in the Department-approved facility plan. These items include, but are not limited to: (2) Population served by project;(3) Existing and proposed wastewater flows;(4) Existing and proposed collection system;(5) Existing and proposed treatment works;(6) Existing and proposed disposal methods;(7) Drinking water system impacts;(8) Hydraulic analysis; andii. Design criteria. The preliminary engineering report shall discuss and present the design criteria applicable to the proposed project. The design criteria includes, but is not limited to: (1) Wastewater flow rates including peak hour flows;(2) Current project fifty (50) year design and build-out conditions;(3) Piping size, material, and installation methods;(4) Depth of bury and slope;(5) Soil and ground water conditions;(6) Corrosion protection; andiii. Code provisions. The preliminary engineering report shall include a summary of applicable codes and standards that apply to the proposed project.iv. Cost estimate. The preliminary engineering report shall provide as applicable estimated construction costs for public works projects or projects funded by public monies.v. Construction schedule. The preliminary engineering report shall include the proposed construction schedule.vi. Environmental review. The preliminary engineering report shall include an environmental review. See the definition for environmental review in Section 010 for additional information.b. Wastewater Pump Station Projects. Items applicable to preliminary engineering reports for wastewater pump station projects include all items listed in Subsection 411.03.a. and items listed in Subsections 411.03.b.i. through 411.03.b.iv. i. Design criteria. The preliminary engineering report shall discuss and present the design criteria applicable to the proposed project. The design criteria includes, but is not limited to: (1) Wastewater flow rates including average day, maximum day, and peak hour flows;(2) Influent wastewater characteristics, including characteristics during periods of wet weather flows;(3) Size and configuration; and(4) Redundancy provisions.ii. Site evaluation and layout. The preliminary engineering report shall describe the proposed site and layout of the wastewater pumping station. This information includes, but is not limited to:(1) Currently proposed facilities;(2) Geotechnical investigation and provisions including buoyancy calculations if required;(3) Flood control provisions;(5) Operations and maintenance assessments; and(6) Odor management plans.iii. Instrumentation and control system. The preliminary engineering report shall discuss instrumentation and control that will be provided. This information includes, but is not limited to:(1) System configuration;(3) Process and instrumentation diagrams; andiv. Emergency operation. The preliminary engineering report shall describe how the system will be operated during power outages, equipment failures, or other unforeseen system failures.c. Wastewater Treatment Plants. Items applicable to preliminary engineering reports for wastewater treatment plant designs and upgrades include all items listed in Subsection 411.03.a., Subsection 411.03.b., and Subsections 411.03.c.i. through 411.03.c.iv. i. Design criteria. The preliminary engineering report shall discuss and present the design criteria applicable to the proposed project. The design criteria includes, but is not limited to: (1) Wastewater flow rates including average day, maximum day, maximum month, and peak hour flows;(2) Effluent requirements;(3) Solids production, disposal, or recycling requirements;(4) Process units design criteria, process selection, and support data;(5) Mass balance calculations for process units including, but not limited to, flow and solids; and(6) Monitoring and reporting requirements.ii. Site evaluation and layout. The preliminary engineering report shall describe the proposed site and layout of the wastewater system. This information includes, but is not limited to: (1) Currently proposed facilities;(2) Facilities for twenty (20) year design conditions;(3) Facilities for build-out conditions;(4) Space for facilities potentially necessary to meet higher levels of treatment;(5) Liquid process facilities and conveyance;(6) Solids process facilities and conveyance;(7) Plant access and on-site roads and walkways;(8) Process piping and utilities;(11) Administration and operations buildings;(12) Onsite laboratory facilities; and(13) Treatment during construction.iii. Hydraulic profile. The preliminary engineering report shall provide a hydraulic profile for the proposed system. This information includes, but is not limited to: (1) Twenty (20) year design facilities;(2) Provision for higher levels of treatment;(3) Receiving stream one hundred (100) year surface water elevation; and(4) Hydraulics and pipe sizing for build-out conditions.iv. Process units. The preliminary engineering report shall describe in detail the proposed process units and discuss how the proposed units will interface with any existing process units. This information includes, but is not limited to: (1) Current project and twenty (20) year design and build-out conditions;(2) Size and number of units and loading rates;(3) Redundancy provisions;(4) Equipment type, size, performance criteria, and power requirements;(5) Structure, equipment, and piping layout;(6) Special code requirements;(7) Cold temperature operation; and(8) Procedures required for initial start-up of process unit(s), including procedures required for handling initial system flows that are less than minimum flow requirements for the process unit(s).04.Engineer's Seal Required. Preliminary engineering reports submitted to the Department shall bear the imprint of an Idaho licensed professional engineer's seal that is both signed and dated by the engineer.Idaho Admin. Code r. 58.01.16.411