Virginia Administrative Code
Title 9 - ENVIRONMENT
Agency 25 - STATE WATER CONTROL BOARD
Chapter 790 - SEWAGE COLLECTION AND TREATMENT REGULATIONS
Part IV - Reports and Forms
Article 1 - Reports
Section 9VAC25-790-940 - Preliminary Engineering Report

Universal Citation: 9 VA Admin Code 9VAC25-790-940

Current through Register Vol. 41, No. 3, September 23, 2024

A. A letter of transmittal consisting of a one-page or more letter typed on the submitting firm's letterhead should be submitted with the Preliminary Engineering Report and should include the following items:

1. Confirmation of a submission of the report to the client;

2. Statement of feasibility of constructing the project; and

3. Identification of all applicable areawide studies project, drainage basin, service area or metropolitan area plans with which the project has been coordinated.

B. A title page shall be included at the beginning of the report and should contain the following information:

1. Title of project and project number;

2. Municipality, county, etc.;

3. Names of officials, managers, superintendents;

4. Name and address of firm preparing report;

5. Seal and signature of appropriate professional in charge of project.

6. Grant number of grant project; and

7. If an expansion, existing certificate or permit number.

C. A table of contents shall be included on the report and should include such listings as:

1. Section headings, chapter headings and subheadings;

2. Maps;

3. Graphs;

4. Illustrations, exhibits;

5. Diagrams; and

6. Appendices.

Number all pages; cross reference by page number.

D. A summary of the findings, conclusions, and recommendations shall be included in the report and should address the following information:

1. Findings. Summarize the findings for the client.
a. Population and design flows--present, design (when), ultimate.

b. Land use and zoning--portion contributed by residential, commercial, industrial, greenbelt, etc.

c. Sewage characteristics and concentrations-portions of total hydraulic, organic, and solids loading attributed to residential, commercial, and industrial fractions and description of sewage nondomestic in character.

d. Sewerage system projects--immediate needs to implement recommended project and deferred needs to complete recommended projects, including pump station, force mains, appurtenances, etc.

e. Selected process--characteristics of process and characteristics of output.

f. Receiving waters--existing water quality and quantity, classifications and downstream water users, and impact of project on receiving water.

g. Total proposed project costs considered for each alternative.

h. Changes-alert client to situations that could alter recommended project.

2. Conclusions. Describe the project as recommended to client for construction.

3. Recommendations. Summarize step-by-step actions, for client to follow to implement conclusions:
a. Official acceptance of report;

b. Adoption of recommended project;

c. Submission of report to regulatory agencies for review and approval;

d. Authorization of engineering services for approved project (construction plans, specifications, contract documents, etc.);

e. Legal services;

f. Enabling ordinances, resolutions, etc., required;

g. Adoption of sewer-use ordinance;

h. Adoption of operating rules and regulations; and

i. Time schedules--implementation, construction, completion dates, reflecting any applicable certificate or permit enforcement actions.

E. An introduction shall be included in the report and should describe the following:

1. Purpose. Reasons for report and circumstances leading up to report.

2. Scope. Coordination of recommended project with area-wide, project, drainage basin, service area or metropolitan area plan and guideline for developing the report.

3. Background: appropriate past history.
a. Existing area, expansion, annexation, intermunicipal service ultimate area.

b. Drainage basin, portion covered.

c. Population growth, trends, increase during design life of facility (graph).

d. Residential, commercial and industrial land use, zoning, population densities, industrial types and concentrations.

e. Topography, general geology and effect on project.

f. Meteorology, precipitation, runoff, flooding, etc., and effect on project.

g. Existing ordinances, rules and regulations, including defects and deficiencies, etc.

h. Recommended amendments, revisions, or cancellation and replacement of local ordinances.

i. Sewer-use ordinance (toxic, aggressive, volatile, etc., substances).

j. Surcharge based on volumes and concentration for industrial waste waters.

k. Existing contracts and agreements (intermunicipal, etc.).

l. Enforcement provision including inspection, sampling, detection, penalties, etc.

F. The report shall include investigative considerations, including an existing facilities evaluation that should address the following as appropriate:

1. Existing sewerage systems:
a. Inventory the existing sewers.

b. Indicate the separation or isolation from water supply wells.

c. Review the collection system capacities and adequacy to meet project needs (structural condition, hydraulic capacity).

d. Tabulate any necessary pipeline or manhole testing, including gauging and infiltration.

e. List any existing points of overflows and required maintenance, repairs and improvements.

f. Outline any necessary rehabilitation, including repair, replacement, and stormwater separation requirements.

g. Establish renovation priorities.

h. Present recommended annual program to renovate sewers.

i. Indicate required annual expenditure.

2. Existing site:
a. Area for expansion.

b. Characteristics of terrain (drainage control).

c. Subsurface conditions.

d. Isolation from habitation (buffer zones).

e. Isolation from water supply structures.

f. Enclosure of unit operations, odor control, noise control.

g. Flood protection.

3. Existing treatment works:
a. Capacities and adequacy of unit operations (tabulate).

b. Relationship or applicability, or both, to proposed project.

c. Age and condition.

d. Adaptability to different usages.

e. Structures to be retained, modified, or demolished.

4. Existing sewage characteristics:
a. Water consumption (from records) (total, unit, industrial).

b. Sewage flow pattern, peaks, total, design flow.

c. Physical, chemical, and biological characteristics, and concentrations.

d. Residential, commercial, industrial, infiltration fractions, considering organic solids, toxic, aggressive, etc., substances (tabulate each fraction separately and summarize).

5. Environmental impact of sewage on receiving waters:
a. Sewage and industrial discharges upstream.

b. Receiving water base flow, min. mean-seven consecutive day drought flow with 10-Year Return Frequency (7Q10).

c. Characteristics (concentrations) of receiving waters.

d. Downstream water uses including water supply, shellfish, recreation, agricultural, industrial, etc.

e. Tabulation of effects on receiving waters.

f. Correlation of treatment works performance versus receiving water requirements.

G. The report shall include a proposed facility evaluation that should address the following as appropriate:

1. Sewerage system.
a. Inventory of proposed additions.

b. Isolation from water supply wells, reservoirs, facilities, etc.

c. Area of service.

d. Unusual construction problems.

e. Utility interruption and traffic interference.

f. Restoration of pavements, lawns, etc.

2. Site requirements. Comparative advantages and disadvantages as to cost, hydraulic requirements, flood control, accessibility, enclosure of unit operations, odor control, landscaping, etc., and isolation with respect to potential nuisances and protection of water supply facilities.

3. Sewage characteristics.
a. Character of sewage necessary to ensure amenability to process selected.

b. Need to pretreat industrial wastewater before discharge to sewers.

c. Portion of residential, commercial, industrial wastewater fractions to comprise projected growth.

d. Impact of proposed discharge on receiving waters--reliability requirements.

e. Tabulation of treatment performance versus receiving water standards.

f. Listing of effluent limitations.

4. Project alternatives.
a. Describe and delineate (line diagrams) each alternative.

b. Preliminary design for cost estimates.

c. Estimates of project's cost (total) (dated, keyed to construction cost index, escalated, etc.).

d. Advantages and disadvantages of each alternative.

e. Individual differences, requirements, limitations.

f. Select preferred alternative.

g. Justify selection and present tabulated comparisons.

h. Characteristics of treatment process performance.

i. Operation and maintenance expenses.

j. Annual expense requirements (tabulation of annual operation, maintenance, personnel, debt obligation).

5. Selected alternative.
a. Construction schedule.

b. Adaptability to future needs.

c. Design flow, variances, and effects on process.

d. Process functions and system backup.

e. Sludge management options.

f. Method of processing of excess combined sewage.

g. Outfall requirements, dispersion, etc.

6. Legal, financing and other considerations.
a. Necessary enabling legislation, ordinances, rules, and regulation.

b. Statutory requirements and limitations.

c. Contractual considerations on intermunicipal cooperation.

d. Public information and education.

e. Effect of state and federal assistance.

f. Exhibit conformance with all applicable federal requirements.

H. The report shall include technical information and design criteria that should address the following as appropriate:

1. Sewerage system.
a. Design tabulations--flow, size, velocities, etc.

b. Regulator or overflow design.

c. Pump station calculations.

d. Special appurtenances.

e. Stream crossings.

f. System map (downstream capacity).

2. Treatment works.
a. Criteria selection and basis of design for principal conventional features and all nonconventional features of the treatment process.

b. Hydraulic and organic loadings, minimum, average, maximum, and effect.

c. Dimensions of unit operations features within treatment process.

d. Rates and velocities of flow through the treatment process.

e. Detention periods provided for unit operations.

f. Concentration values projected for influent and effluent flows.

g. Recycle flows and rates within total treatment process.

h. Chemical additive control methods.

i. Physical control methods for rates of flow, etc.

j. A separate tabulation for performance ratings and treatment efficiencies of unit operations relative to residual solid and liquid processing.

k. Sludge management method.

l. Process configuration, interconnecting piping, processing, flexibility, etc.

m. Hydraulic flow profile.

n. Residual solids or sludge processing, including dewatering.

o. Unit operations flow diagram with capacities, etc.

3. Laboratory.
a. Physical and chemical tests and frequency to control process.

b. Time for testing.

c. Space and equipment requirements.

d. Personnel requirements--number, type, qualifications, salaries, benefits (tabulate).

4. Operation and maintenance.
a. Routine and special maintenance duties.

b. Time requirements.

c. Tools, equipment, vehicles, safety, etc.

d. Personnel requirements--number, type, qualifications, salaries, benefits (tabulate).

e. Processes needing chemical addition.

f. Chemicals and feed equipment.

g. Pump stations or regulator or overflow inspection and repair.

h. Flow gauging.

i. Industrial sampling and surveillance.

j. Ordinance enforcement.

k. Equipment requirements.

l. Trouble-call investigation.

m. Industrial pretreatment permits.

I. Management systems shall be described in the report including the following information as appropriate:

1. Personnel-recommended operator classification.

2. Equipment.

3. Chemicals.

4. Utilities.

5. Outline unusual specifications, construction materials, and construction methods.

6. Maps, photographs, diagrams (report size).

Statutory Authority

§ 62.1-44.19 of the Code of Virginia.

Disclaimer: These regulations may not be the most recent version. Virginia may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
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