Section 120. Construction drawings (plans)

A. Construction drawings (plans) for sewerage systems or treatment works improvements for which a technical evaluation is required shall provide the information necessary to determine that the owner's final plans, specifications, and other documents satisfy (i) requirements established by these regulations and engineering standards of practice; and (ii) the minimum requirements and limiting factors established in the owner's approved preliminary engineering proposal. The final plans should include:

B. Final engineering documents. Drawings, plans, specifications and other engineering documents that are submitted to the area engineer for a technical evaluation shall be in substantial compliance with this chapter prior to issuance of a CTC by the director. Engineering documents may be submitted by the owner to the area engineer following the preliminary engineering conference, or following a technical evaluation of the preliminary engineering proposal if required. Up to four copies shall be submitted to the area engineer for non-Virginia Revolving Loan Fund funded projects and up to five copies shall be submitted for projects financed through the Virginia Revolving Loan Fund. The original of the letter of submittal with appropriate signature(s) shall accompany the engineering documents. The letter of submittal should identify any necessary actions to be taken by the area engineer to expedite evaluation of the submitted documents.

All drawings, specifications, engineer's reports and other documents submitted for evaluation shall be prepared by or under the supervision of appropriately licensed professionals, legally qualified to practice in Virginia, in accordance with the provisions of §§ 54.1-400 to 54.1-411 of the Code of Virginia inclusive.

All submitted plans for sewerage systems or treatment works shall bear a suitable title showing the name of the municipality, sewer district, institution or other owner and shall show the scale in feet, a graphical scale, the north point, date and the name of the appropriate licensed professional. Also, each plan sheet shall bear the same general title identifying the overall project, and each shall be numbered. Appropriate subtitles shall be included on the individual sheets. The plans shall be clear and legible. They shall be drawn to a scale that will permit all necessary information to be plainly shown. The size of the plans should be no larger than 36 inches by 48 inches. The datum used should be indicated. Locations of all special features, when made, shall be shown on the plans. Logs of test borings should be given either on plans or in the specifications. Detail plans shall consist of plan views, elevations, sections, and supplementary views which, together with the specifications and general layouts, provide the working information for the contract and construction of the works. The plans shall include dimensions and relative elevations of structures, the location and outline form of equipment, location and size of piping, water levels, ground elevations, and erosion control abatement facilities. Data shall be provided for proposed additions of flow to existing sewerage systems indicating that the additional sewage flow from the proposed project will have no adverse impact on the operation of downstream facilities.

C. Sewerage systems. Plans submitted for new construction or substantial modification (increasing flow capacity by more than 25%) of sewage collection piping shall include the following: the location, size, type and direction of flow of all existing and proposed sanitary sewers involved in the project.

1. Detailed plans when submitted for evaluation shall provide complete and properly scaled graphical depictions of design information. Profiles shall have a horizontal scale of not more than 100 feet to the inch and a vertical scale of not more than 10 feet to the inch. The plan view shall be drawn to a corresponding horizontal scale. Plans and profiles shall show:

a. Location of streets and sewers with an identification system.

b. Ground surface elevations and manhole stationing.

c. Invert elevations of sewers at each manhole.

d. Size and grade of sewer between adjacent manholes.

e. Any special construction features.

2. All manholes shall be labeled in an established manner on the plan and correspondingly labeled on the profile. If a community does not allow the connection of basement drains to the sewer, this may be stated on the plans as a basis for exemption, and the plans need not show the elevations and locations of basement floors. Where there is any question of the sewer being sufficiently deep to serve any residence, the elevation and location of the basement floor shall be plotted on the profile of the sewer which is to serve the house in question. The engineer shall state that all sewers are sufficiently deep to serve adjacent basements except where otherwise noted on the plans.

3. Sewerage system plans shall identify locations of all special features such as inverted siphons, concrete encasement, elevated sewers, all known existing structures both above and below ground that might interfere with the proposed construction, particularly water mains, gas mains, storm drains, etc.

4. Special detail drawings, made to a scale to clearly show the nature of the design, shall be furnished to show the following particulars:

a. All stream crossings and sewer outlets, with elevations of the streambed and normal and design flow water levels.

b. Details of all sewer joints and cross sections requiring special construction such as concrete encasement.

c. Details of all sewer appurtenances such as manholes, inspection chambers, inverted siphons, regulators, tide gates and elevated sewers.

D. Sewage pumping stations. Plans submitted for technical evaluation involving new construction or substantial modification (increasing flow capacity by more than 25%) of pumping stations shall address the following design information: (i) the location and extent of the tributary area; (ii) the location of municipal boundaries within the tributary area; and (iii) the location of the pumping station and force main and pertinent elevations.

1. For new construction the forms of land use (commercial, residential, and agricultural) and access control proposed for the near future over a 100-foot radius from the pumping station structure shall be indicated. Existing buildings and their types within 100 feet of the pumping station shall be indicated. Submission of detailed plans would not be required for upgraded pump stations that are issued, or included in, a final operating permit.

2. Detailed plans submitted for evaluation shall provide the following design information where applicable:

a. A contour map of the property to be used.

b. Proposed pumping station equipment layout and capacities including provisions for installation of future pumps or ejectors. Proper references to the specifications should be included.

c. Elevations of operating levels of sewage contained in the wet well at the site and the estimated locations of raw sewage overflows in the collection system upon occasion of pump failure resulting in high water levels in the wet well.

d. Test borings and ground water elevations, if taken.

e. Plan and elevation views of the pump suction (from the wet well) and discharge piping showing all isolation valves and gates.

E. Treatment works. Plans submitted for technical evaluation of projects involving new construction or substantial modifications (increasing flow capacity by more than 25%) of treatment works shall identify the treatment works relative to the remainder of the system. For new construction, the plan shall include sufficient topographic features to indicate its location relative to streams and the point of discharge of treated effluent. Also the forms of land use (commercial, residential, and agricultural, existing or proposed) and access controls for the near future over a 700-foot radius from the proposed treatment works structures must be indicated. Existing buildings and their type of use within 700 feet of the new treatment works site shall be adequately described, e.g., by means of topographic maps, aerial photos, drawings, etc.

1. For technical evaluation, the proposed treatment works design submittal shall include the following as specified:

a. Topography and other characteristics of the site as specified:

b. Size and location of treatment works structures.

c. Schematic flow diagram showing the flow through various treatment works unit operations.

d. Piping, including any arrangements for bypassing individual unit operations. Materials handled and direction of flow through channels, pipes and unit operations shall be shown, including arrangements for independent operation.

e. Hydraulic flow profiles showing the average relative surface elevations of mainstream and sidestream flows of sewage, supernatant and sludge as influent, effluent and flow within the channels, piping, pumps and basins that comprise the treatment works.

f. Soil characteristics including hydraulic conductivity established by soil tests and test borings and hydrologic factors, such as ground water elevations, that can affect the treatment of disposal capacity.

2. For technical evaluation, detailed plans shall include the following:

a. Location, dimensions and elevations of all existing and proposed treatment works unit operations solids handling facilities and equipment.

b. Elevations of high water levels affecting the treatment works design and to which the treatment works effluent is to be discharged or absorbed.

c. Pertinent data concerning the rated capacity of all pumps, blowers, motors and other mechanical devices. All or part of such data may be included in the specifications by suitable reference on the plans.

d. Average and maximum elevations for the hydraulic flow profile within the unit operations.

e. Adequate description of any features not otherwise covered by specifications or engineer's report.

3. Facility closure plans shall address the following information as a minimum:

a. Residual wastewater and solids treatment, removal and final disposition.

b. Removal of structures, equipment, piping and appurtenances.

c. Site grading and erosion and sediment control.

d. Restoration of site vegetation and access control.

e. Proposed land use (post-closure) of site.

F. Plans submitted for technical evaluation of biosolids use facilities, including substantial modifications (new location of storage on site, or increasing design capacity by more than 20%) from that previously approved shall identify the proposed locations, management practices, biosolids sources, treatment and quality information as required. For new construction, the plan shall include sufficient topographic features to indicate its location relative to streams and other land use facilities, as required. The forms of land use (commercial, residential, and agricultural existing or proposed) buffer zones and access controls, for the near future, surrounding the proposed biosolids use facilities must be indicated. Existing buildings and their type of use within 200 feet of the new site shall be adequately described (e.g., by means of topographic maps, aerial photos, drawings, etc.).

Facility closure plans shall address the following information as a minimum:

1. Residual wastewater and sludge treatment, removal and final disposition.

2. Removal of structures, equipment, piping and appurtenances.

3. Site grading and erosion and sediment control.

4. Restoration of site vegetation and access control.

5. Proposed land use (postclosure) of site.

.G. Approval. The area engineer will approve or disapprove the construction drawings and notify the owner in accordance with 9VAC25-790-80 C.

Historical Notes

Former 12VAC5-581-170 derived from Volume 18, Issue 10, eff. February 27, 2002; amended and adopted as 9VAC25-790-120, Virginia Register Volume 20, Issue 09, eff. February 12, 2004; amended, Virginia Register Volume 24, Issue 06, eff. January 1, 2008.

Statutory Authority

§ 62.1-44.15 of the Code of Virginia.