01d. Attachment D-Basis of Design Requirements 7 15 2026.docx

Attachment D- Basis of Design Requirements Note: If an industry standard and a military regulation conflict on the same attribute, the stricter limit applies.

Design Requirements – Backflow Prevention Assemblies

1.0 Introduction

This memorandum outlines the design and installation criteria for backflow prevention assemblies required to protect the potable water supply. These assemblies are critical for preventing the reverse flow of non-potable water or other substances into the distribution system. Installations will occur at two key locations: one to isolate Pump Station 2, and a second isolate at the Tee connection, future location of a new water tank and SOR Pump Station, located just east of the SOR Guard House.

2.0 References

All design, selection, and installation work shall comply with the latest editions of the following standards:

· UFC 3-420-01: Plumbing Systems

· AWWA C511: Reduced-Pressure Principal Backflow Prevention Assembly

· AWWA Manual M14: Recommended Practice for Backflow Prevention and Cross-Connection Control

· Local and State Environmental Protection and Health Department plumbing codes.

3.0 Backflow Preventer Design Requirements

The selection and configuration of the backflow prevention assemblies shall adhere to the following specifications to ensure maximum protection of the water system.

locations. RPZ assemblies provide the highest level of protection suitable for high-hazard cross-connections, such as those associated with pump stations and complex distribution points.

2. SOR Guard House Tee: The assembly will be installed on the lateral service line at the tee connection just east of the SOR Guard House to protect the upstream main line from potential back-siphonage or back-pressure from the facility.

4.0 Testing and Commissioning

Upon installation, each backflow prevention assembly must be commissioned and tested to ensure it is functioning correctly and in compliance with all regulatory requirements.

· Field Testing: Each RPZ assembly must be tested by a certified backflow prevention assembly tester immediately after installation and before the system is put into service. Testing shall be conducted in accordance with the procedures outlined in UFC 3-420-01 and any applicable local regulations.

· Documentation: A copy of the successful test report for each assembly must be submitted to the Project Manager and kept on file for regulatory compliance.

· Annual Testing: The facility owner will be responsible for ensuring that each backflow prevention assembly is tested at least annually by a certified tester to maintain continued protection of the water supply.

Design Requirements – Check Valve Design & Installation

1.0 Introduction

This memorandum provides the design and installation criteria for check valves to be installed on the discharge side of pumps within the system. The primary function of these valves is to automatically prevent backflow when a pump is shut off. This action is critical to protect the pump from damage caused by back pressure and reverse rotation, and to mitigate hydraulic shock (water hammer) within the piping system.

2.0 References

All valve selection and installation shall be performed in accordance with the latest editions of the following standards:

· AWWA C508: Swing-Check Valves for Waterworks Service, 2-In. through 48-In. (50-mm through 1,200-mm) NPS

· AWWA M44: Distribution Systems: Steel Water-Pipe Design and Installation

· UFC 3-201-01: Civil Engineering

3.0 Check Valve Design and Installation Requirements

The following requirements shall govern the selection and placement of all check valves installed for pump discharge applications.

4.0 Submittals and Quality Assurance

The contractor shall select the type, brand and location of these valves. To ensure the correct product is installed, the contractor shall submit manufacturer's technical data sheets for the proposed check valves for engineering review and approval prior to procurement. The data sheets must verify compliance with the specified valve type, pressure rating, and all referenced AWWA standards. During installation, inspection will confirm correct orientation and placement as per the design drawings.

Design Requirements – Isolation Valve Installation

1.0 Introduction

This memorandum details the design, selection, and installation requirements for isolation valves within the water distribution system. The purpose of these valves is to provide precise flow control, allow for the isolation of in-line equipment for maintenance, and facilitate bypass operations. Adherence to these specifications is critical for ensuring system reliability, safety, and operational flexibility.

2.0 References

All valve selection and installation work shall be performed in accordance with the latest editions of the following standards:

· AWWA C504: Rubber-Seated Butterfly Valves, 3 In. (75 mm) and Larger

· AWWA C512: Air-Release, Air/Vacuum, and Combination Air Valves for Waterworks Service

· AWWA M44: Distribution Systems: Steel Water-Pipe Design and Installation

· UFC 3-201-01: Civil Engineering

3.0 Valve Design and Configuration Requirements

The following requirements shall govern the selection and placement of all isolation valves for this project.

A minimum of seven (7) butterfly valve assemblies will be installed along the new line “upstream” of Pump Station 2. One will be placed before the connection to the C900 pipe just east of the SOR Guard House on the eastern edge of the proposed new line. The Tee area is in the area east of the SOR Guard House. Three (3) will be placed at the location of the Tees. One (1) on the Pipe teeing off to the south for the future water tank. One (1), Tee installed in between the Tees fitting on the main line. One (1) on the Pipe teeing off to the south for the future SOR Pump Station. Three (3) shall be placed at approximately equal spacing from Pump Station 2 along the line to the location of the Tees.

Installation & Operation Each valve shall be installed within a dedicated valve box that extends to the finished grade. The valve must be equipped with a 2-inch square operating nut to allow for manual operation from the surface using a standard T-handle valve key. Valve boxes must be centered over the operating nut and provide adequate clearance.

4.0 Quality Assurance and Control

Proper installation is critical to the long-term performance of the isolation valves. The contractor shall ensure that valves are installed plumb and are not subjected to stress or misalignment from the connecting pipe. Following installation and backfill, all valves must be operated through a full open-close cycle to verify proper function and to confirm that the operating nut is accessible and unobstructed within the valve box. Any valve found to be inoperable or difficult to access shall be corrected before system activation.

Design Requirements – Security Fencing and Access Gates

1.0 Introduction & Purpose

This memorandum establishes the comprehensive basis of design for the security fencing system to be installed at the SOR Facility & HERTF Infrastructure Upgrades project. The purpose is to provide a robust physical security barrier to deter unauthorized access and protect sensitive equipment.

The scope includes the design, furnishing, and installation of a complete security fencing system, including all fabric, posts, hardware, and access gates required to fully enclose the new 15,000-gallon tank and Pump Station 2 site, as well as the new 5,000-gallon tank and pump station at the SOR site.

2.0 Scope of Work

This work includes the design, furnishing, and installation of a complete security fencing system. The scope includes all fencing fabric, posts, top rails, hardware, and vehicle access gates required to fully enclose the new 15,000-gallon tank and Pump Station 2 site, as well as the new 5,000-gallon tank and pump station at the SOR site.

3.0 Governing Standards & Codes

Design and installation shall comply with the latest editions of the following standards:

· Primary Governing Standards:

· UFC 4-022-03: Security Fences and Gates

· AWWA G430: Security Practices for Operation and Management

· Supporting Standards:

· UFC 4-010-01: DoD Minimum Antiterrorism Standards for Buildings

· UFC 3-201-02: Landscape Architecture (for site clearing/restoration)

· AWWA Manual M19: Emergency Planning for Water Utilities

· EM 385-1-1: Safety and Health Requirements Manual

4.0 Design Criteria

Prior to construction, the following site-level planning actions are required to ensure compliance and proper installation.

Gate Width Verification The design team must verify the dimensions of the largest maintenance vehicle (e.g., crane, pump truck) to confirm the required clear opening width for the vehicle gate. A minimum of 20 to 24 feet is anticipated.

4.1 Fencing System

4.2 Detailed Access Gate Specifications

The vehicle access gate shall be constructed to be as physically resistant to forced entry as the fence itself.

5.0 Requirements

1. Confirm Gate Width: Verify the dimensions of the largest maintenance vehicle required access to the site to finalize the required clear opening width for the gate.

2. Site Survey: Conduct a detailed site survey to finalize the fence alignment, identify any grading requirements, determine the exact locations for all posts and grounding rods.

3. Development Construction Details: Create detailed design drawings showing the fence and gate layout, post footing details, and grounding plan in accordance with UFC requirements.

Design Requirements – Spoil Management

1.0 Introduction & Purpose

This memorandum establishes the basis of design for the management of all spoil (excavated earth, rock, and other materials) generated during the project. A systematic approach to spoil management is required to ensure environmental compliance, maintain a safe and orderly worksite, and properly handle materials for either reuse or disposal.

The purpose is to define the procedures for the characterization, stockpiling, on-site reuse, and off-site disposal of all excavated materials.

2.0 Scope of Work

This work includes the comprehensive management of all materials excavated from trenches, foundations, and other site work areas. The scope covers the following activities:

· Segregation of topsoil from subgrade materials during excavation.

· On-site stockpiling of excavated materials.

· Characterization of spoil to determine its suitability for reuse as backfill.

· Loading, hauling, and placement of suitable material for reuse.

· Loading, hauling, and legal off-site disposal of all excess or unsuitable spoil.

3.0 Governing Standards & Codes

The management of spoil shall comply with the latest editions of the following standards and regulations:

· Unified Facilities Criteria (UFC) / Unified Facilities Guide Specifications (UFGS):

· UFC 3-201-01: Civil Engineering (Establishes overarching site work requirements).

· UFGS 31 20 00: Earth Moving (Primary standard for excavation, stockpiling, and backfill).

· UFGS 31 23 16.13: Trenching (Provides specific requirements for trench spoil).

· Environmental Regulations:

· Stormwater Pollution Prevention Plan (SWPPP): Governs erosion and sediment control for stockpiles.

· Albuquerque/Bernalillo County Air Quality Program (AQP): Specifically, regulations pertaining to fugitive dust control (e.g., 20.11.20 NMAC).

· Safety:

· EM 385-1-1: Safety and Health Requirements Manual (Governs stockpile safety and material handling).

4.0 Design Criteria

4.1 Excavation and Segregation

· During excavation, topsoil shall be stripped and segregated from the underlying subgrade soils and rock.

· Topsoil shall be stockpiled separately for reuse during final site restoration and landscaping.

4.2 On-Site Stockpiling

· All spoil stockpiles shall be located in pre-approved areas, away from drainage channels, sensitive habitats, and operational zones.

· Stockpiles must be managed to prevent erosion and sedimentation. This includes implementing Best Management Practices (BMPs) as defined in the project's SWPPP, such as silt fencing around the stockpile perimeter.

· Stockpiles must be managed to control fugitive dust in compliance with local air quality regulations. This may include periodic watering or the use of other dust suppressants.

· Stockpiles shall be shaped to maintain stable slopes and prevent collapse, in accordance with EM 385-1-1 safety requirements.

4.3 Spoil Characterization and Reuse

· Excavated subgrade spoil shall be continuously evaluated by a qualified geotechnical professional to determine its suitability for reuse as trench or structural backfill.

· Suitable Material: Material that is free of debris, organic matter, frozen material, and rocks larger than 3 inches in diameter may be considered suitable for reuse as general or main backfill.

· Unsuitable Material: Material that does not meet the criteria for "Suitable Material" shall be deemed unsuitable for reuse. This includes material with excessive moisture, cobbles/boulders, or contamination.

· All suitable material designated for reuse must be placed and compacted to the percentages specified in the project's geotechnical and design requirements.

4.4 Off-Site Disposal of Excess and Unsuitable Spoil

· All excess spoil (material remaining after backfill operations are complete) and all spoil deemed unsuitable for reuse shall be removed from the project site.

· The Contractor is responsible for loading, hauling, and legally disposing of all such materials.

· Disposal must occur at a licensed and permitted facility capable of accepting the type of material being removed. The Contractor shall be required to provide disposal tickets or other documentation as proof of legal disposal.

5.0 Requirements

1. Develop a Spoil Management Plan: The Contractor must submit a detailed, written Spoil Management Plan for approval before major excavation begins. The plan must identify the proposed locations for stockpiles, dust and erosion control measures, and the intended disposal site for excess spoil.

2. Identify and Approve Disposal Site: The Contractor must identify the proposed off-site disposal facility and provide documentation confirming the facility is licensed to accept the material.

3. Coordinate with Geotechnical Engineer: Ensure a geotechnical professional is scheduled to be on-site during initial excavation activities to assist with the characterization of spoil materials.

Design Requirements – Surface Restoration for Waterline Installation

1.0 Introduction

This memorandum outlines the design and construction requirements for surface restoration following trenching and the installation of a new waterline. The procedures detailed herein are in accordance with Unified Facilities Criteria (UFC) and American Water Works Association (AWWA) standards to ensure a safe, durable, and long-lasting restoration.

2.0 References

All work shall be performed in accordance with the latest editions of the following standards:

· UFC 3-201-01: Civil Engineering

· UFC 3-250-01: Pavement Design for Roads and Parking Areas

· AWWA C600: Installation of Ductile-Iron Water Mains and Their Appurtenances

· AWWA C651: Disinfecting Water Mains

· AWWA C900: Polyvinyl Chloride (PVC) Pressure Pipe, 4-Inch through 12-Inch, for Water Distribution

· ASTM D698: Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Standard Effort

· ASTM D1557: Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Modified Effort

· Occupational Safety and Health Administration (OSHA) 29 CFR Part 1926, Subpart P: Excavations

3.0 Trenching and Excavation

Proper trenching and excavation are critical for the safety of the crew and the integrity of the installation.

Shoring and Bracing All excavations shall comply with OSHA regulations.

Shoring, bracing, or trench boxes are required for trenches 5 feet deep or greater, or in unstable soil conditions.

4.0 Trenching and Excavation

Proper bedding and backfill are essential to support the pipe and prevent settlement. Please refer to the Design Requirements – Basis of Design 7900 – Foot 8- Inch Potable Water Main Design and Construction.

5.0 Compaction Requirements

Achieving the correct compaction density is crucial to prevent future settlement and pavement failure.

Compaction testing shall be performed at a frequency of one test per 200 linear feet of trench per two feet of fill thickness.

6.0 Pavement Restoration

Pavement restoration must be completed to restore the structural integrity and ride quality of the roadway.

Pavement Type Procedure

2. Base Course: A minimum of 10 inches of aggregate base course (ABC) compacted to 95% of the Modified Proctor (ASTM D1557) maximum dry density shall be placed.

3. Pavement Replacement: The asphalt or concrete pavement shall be replaced to a thickness equal to or greater than the existing pavement. All pavement repairs in public rights-of-way must meet the requirements of the governing transportation department.

7.0 Quality Control and Testing

All installations are subject to rigorous testing to ensure compliance with all applicable standards.

· Hydrostatic Testing: After backfilling, the new waterline shall be subjected to a hydrostatic pressure test at a minimum of 150 psi for two hours.

The allowable leakage shall be calculated using the formula in AWWA C600.

· Disinfection and Bacteriological Testing: The new main shall be disinfected in accordance with AWWA C651, followed by bacteriological testing to ensure the water is safe for consumption.

· Backfill Compaction Testing: Field density tests will be conducted to verify that the specified compaction requirements are met. Any areas that fail to meet the required density shall be re-excavated, re-compacted, and re-tested at the contractor's expense.

Design Requirements - 5,000-Gallon Welded Steel Tank & Site Work at SOR

This memorandum establishes the basis of design for the new 5,000-gallon potable water storage tank, its engineered foundation, and all associated site work to be located at the SOR site. This scope of work is associated with Design and Construction.

The purpose of this installation is to provide dedicated water storage for the new SOR pump station. The design includes necessary bypass piping to ensure operational flexibility for maintenance and emergencies. The Government assumes this tank will be shop fabricated and delivered to the site.

2.0 Governing Standards & Codes

The design, fabrication, and construction shall comply with the latest editions of the following primary standards:

· Unified Facilities Criteria (UFC):

· UFC 3-230-01: Water Supply, Treatment, and Distribution.

· UFC 3-301-01: Structural Engineering (for foundation design).

· UFC 4-022-03: Security Fences and Gates.

· American Water Works Association (AWWA):

· AWWA D100: Welded Carbon Steel Tanks for Water Storage (Primary standard).

· AWWA B-Series: For coating systems (e.g., D102 for painting).

· AWWA C504: Rubber-Seated Butterfly Valves.

· AWWA C151: Ductile-Iron Pipe and Fittings.

3.0 Design Criteria

3.1 Welded Steel Tank & Foundation

· Tank:

· Capacity: 5,000-gallon nominal capacity.

· Standard: Shop-fabricated, welded carbon steel construction in full compliance with AWWA D100.

· Coatings: Interior shall be an NSF/ANSI 61 certified epoxy system. The exterior shall receive a multi-coat industrial urethane system for corrosion and UV protection per AWWA D102.

· Foundation:

· An engineered reinforced concrete foundation shall be designed per UFC 3-301-01 and ACI 318.

· The design must be based on a site-specific geotechnical investigation to determine soil bearing capacity, frost depth, and seismic requirements.

· Tank Appurtenances (per AWWA D100):

· Inlet and Outlet pipe connections.

· Overflow pipe with a flap gate and splash pad.

· Shell manway (24-inch minimum).

· Roof manway (30-inch minimum).

· Exterior caged ladder with a lockable security gate.

· Roof safety railing.

· Vent assembly sized for maximum fill/drain rate.

· Level indicator (local float-type and electronic for SCADA).

3.2 Site Security

· Fencing: The entire tank and pump station area shall be enclosed by an 8-foot-high chain-link security fence with a top rail and tension wire, compliant with UFC 4-022-03.

· Gate: A commercial-sized sliding gate shall be installed to provide access for maintenance vehicles.

· Please see Design Requirements – Security Fencing and Access Gates.

3.3 Site Piping and Valves

· Piping Material: All below-grade process piping shall be Ductile Iron Pipe (DIP).

· Isolation Valves: All isolation valves shall be Rubber-Seated Butterfly Valves per AWWA C504, installed in valve boxes with operating nuts.

· Bypass Configuration: The piping shall be configured to allow the tank and new SOR pump station to be taken offline for maintenance without interrupting the main water supply. This requires a bypass line around the new tank and pump station, allowing flow to continue to downstream facilities.

· Please see Design Requirements 8-Inch Bypass and Isolation System.

A detailed piping schematic will be developed by the Designer of Record showing the isolation valves required to achieve this bypass functionality.

4.0 Requirements

1. Conduct Geotechnical Investigation: This is mandatory for the foundation design and must be completed before structural drawings are developed. This investigation should include all new facility sites.

2. Develop Detailed Piping & Instrumentation Diagram (P&ID): Create a formal P&ID to finalize the layout of the bypass valves and all connections.

3. Obtain Tank Vendor Shop Drawings: Select a tank manufacturer to provide detailed fabrication drawings for review and coordination with the foundation and piping design.

This memo established the design basis for the 5,000-gallon SOR tank project.

Design Requirements - Basis of Design ~ 7,900-Foot 8-Inch Potable Water Main Design and Construction

This memorandum establishes the basis of design for the design and construction of a new, approximately 7,900-foot-long, 8-inch ductile iron water main. The purpose of this pipeline is to provide a high-pressure potable water supply.

This design is based on the provided route alignment and incorporates specific requirements for materials, joint restraint, and trenching procedures necessary to accommodate high pressure and challenging soil conditions. All work shall conform to the governing UFC and AWWA standards.

2.0 Governing Standards & Codes

The design and construction of the waterline shall comply with the latest editions of the following primary standards:

· Unified Facilities Criteria (UFC):

· UFC 3-230-01: Water Supply, Treatment, and Distribution.

· UFC 3-301-01: Structural Engineering (for any related structures).

· American Water Works Association (AWWA):

· AWWA C105/A21.51: 8-inch, Pressure Class 350 potable water line with both factory asphaltic coating and field-applied polyethylene encasement under AWWA C105. (AWWA C105 / ANSI A21.5: Polyethylene Encasement for Ductile-Iron Pipe Systems.)

· AWWA C104/A21.4: Cement-Mortar Lining for Ductile-Iron Pipe and Fittings.

· AWWA C111/A21.11: Rubber-Gasket Joints for Ductile-Iron Pressure Pipe and Fittings.

· AWWA C600: Installation of Ductile-Iron Water Mains and Their Appurtenances.

· AWWA Manual M41: Ductile-Iron Pipe and Fittings.

Table 1 Pipe Dimensions

3.0 Design Criteria

3.1 Pipe Material & Specifications

· Pipe: 8-inch Ductile Iron Pipe (DIP).

· Manufacturing Standard: Centrifugally cast per AWWA C151.

· Thickness Class: Class 52.

· Lining: Standard Cement-Mortar Lining per AWWA C104.

· Coating: Standard Asphaltic Coating (approx. 1 mil thick).

Table 2 Required Pipe Standards

· Fittings: AWWA C110, ductile iron, rated for Pressure Class 350 Ductile Iron Pipe minimum working pressure. All fittings shall be of the same manufacturer as the pipe, where possible.

3.2 Joint Restraint System

· Requirement: Due to the high operating pressure of about 300 psi, all pipe joints, fittings, and valves shall be fully restrained.

· Method: Wedge-Action Joint Restraint Assemblies (e.g., MEGA-LUG® or approved equal) designed for use with mechanical joints shall be used. This method is preferred as it eliminates the need for most concrete thrust blocks, providing a consistent and reliable restraint mechanism along the entire pipeline. A similar approach can be approved if approved by the COR.

3.3 Route & Installation Depth

· Route: The pipeline shall be installed generally along the route provided in the project plans. If a change of route is requested this must be approved by the COR.

· Frost Depth: The specified frost depth for the region is 36 inches. All piping shall be installed to provide a minimum of 48 inches (4 feet) of cover over the top of the pipe to ensure adequate protection against freezing and surface loads, in compliance with UFC 3-230-01.

3.4 Trenching, Bedding, and Backfill Please review the Design Requirements – Pipe Installation and Trenching.

In compliance with UFC 3-230-01, a specific trench detail is required to ensure pipe stability and protection, particularly in areas with cobbles.

· Trench Dimensions:

1. Depth: The bottom of the trench will be approximately 5.5 feet (65 inches) deep to achieve the required 48 inches of cover over the pipe.

2. The minimum width should be between 3 to 4 feet (36 to 48 inches) at the bottom to provide adequate working space.

· Subgrade Preparation:

1. The trench shall be over-excavated by 8 inches below the required pipe bottom elevation.

2. Where suitable native soil exists, it shall be compacted to 95% of the Standard Proctor Maximum Dry Density (ASTM D698). Unsuitable material (large rocks, debris) shall be removed and replaced.

· Bedding:

1. An 8-inch layer of appropriate bedding material shall be placed and compacted in 6-inch lifts to 95% on top of the prepared subgrade.

2. Bedding material shall be crushed stone, gravel, or coarse sand conforming to AWWA C600 Class 3 or Class 4 material, with a maximum particle size of 3/4 inch to ensure uniform support and protect the pipe coating.

3. Bell holes shall be excavated to accommodate pipe bells and joints.

· Pipe Placement & Haunching:

1. The pipe shall be carefully placed on the prepared bedding.

2. Bedding material shall be placed around the pipe and hand-compacted in 6-inch lifts to an elevation 8 inches above the top of the pipe. All material under the pipe haunches must be consolidated to provide full support. The compaction requirement for this zone is 95% Standard Proctor.

· Final Backfill:

1. The remainder of the trench shall be backfilled using suitable native soils, placed in lifts not exceeding 12 inches (loose). Each lift shall be mechanically compacted to grade as required by the surface finish (e.g., 95% for roadway areas, 90% for landscaped areas).

· Compaction Requirements Achieving the correct compaction density is crucial to prevent future settlement and pavement failure.

· Compaction testing shall be performed at a frequency of one test per 200 linear feet of trench per two feet of fill thickness.

4.0 Required Steps

1. Geotechnical Potholing: Some potholing may be required at regular intervals along the proposed route to verify soil conditions, confirm the extent of cobbles. In The area near SOR potholing may be required to identify underground utility conflicts not shown on existing plans.

2. Hydrostatic Testing Plan: Develop a detailed hydrostatic testing plan in accordance with AWWA C600. Given the high pressure, this plan must include specific safety protocols for the test section setup and execution.

3. Traffic Control Plan: Although most of the work is off-road some traffic control may be required to close the alignment along the dirt road. A comprehensive traffic control plan will be required for all work performed within or near existing roadways.

This memo provides the basis of design for the new 8-inch waterline. Detailed construction plans and specifications should be developed in accordance with these criteria.

Design Requirements – 8-Inch Smart Water Meters

1.0 Introduction & Purpose

This memorandum establishes the basis of design for the installation of new 8-inch "smart" water meters at key locations within the water distribution network. The purpose of these meters is to provide accurate, real-time flow and volume data for operational monitoring, water accountability, and as a critical input to the SCADA leak detection system.

A "smart" meter, in this context, is defined as a high-precision metering device with an electronic output signal for seamless integration with the main SCADA network.

2.0 Scope of Work

This work includes the design, furnishing, installation, and commissioning of two (2) new 8-inch smart water meters. If option 1 and/or 2 are exercised one of these shall be installed on the outlet side of the new SOR Pump Station. The scope includes the meter itself, any required vaults or enclosures, and all necessary electrical and communication wiring to connect the meters to the SCADA system.

3.0 Governing Standards & Codes

The design, selection, and installation shall comply with the latest editions of the following standards:

· Unified Facilities Criteria (UFC):

· UFC 3-230-01: Water Supply, Treatment, and Distribution (Governs installation and location).

· UFC 3-501-01: Electrical Engineering (Governs power and signal wiring).

· UFC 4-010-06: Cybersecurity of Facility-Related Control Systems (As a SCADA component).

· American Water Works Association (AWWA):

· AWWA C715: Cold-Water Meters—Electromagnetic and Ultrasonic Type, for Revenue Service (Primary standard for this meter type).

· AWWA M6: Water Meters—Selection, Installation, Testing, and Maintenance.

· AWWA M33: Manual of Water Supply Practices, Flow-Measuring Devices.

· AWWA C600: Installation of Ductile-Iron Water Mains and their Appurtenances.

4.0 Design Criteria

4.1 Meter Technology and Performance

· Type: Full-bore, flanged, in-line Electromagnetic (Mag Meter) or Transit-Time Ultrasonic spool-piece meter. This technology is preferred for its high accuracy, wide flow range, and lack of moving parts, which minimizes maintenance and pressure loss.

· Size: 8-inch nominal diameter.

· Accuracy: The meter shall have a certified accuracy of ±1.0% of reading or better across its specified operating range.

· Compliance: The meter must be fully compliant with AWWA C715 and be certified for potable water use under NSF/ANSI 61.

4.2 Installation Requirements

· Location: Meters shall be installed in below-grade precast concrete vaults for protection and accessibility. Vaults must include a sump, drain, and an appropriate access hatch.

· Piping Configuration:

· The meter must be installed in a horizontal run of pipe.

· To ensure accuracy, the installation must adhere strictly to the manufacturer's requirements for minimum upstream and downstream straight-pipe lengths (typically 5-10 pipe diameters upstream and 2-5 diameters downstream).

· A full-service bypass line with isolation valves (butterfly valves) must be installed around each meter assembly. This allows the meter to be removed for calibration or maintenance without interrupting service.

· Grounding: For electromagnetic meters, grounding rings and straps must be installed per the manufacturer's instructions to eliminate electrical noise and ensure accuracy.

4.3 Electrical and SCADA Integration

· Power Supply: The meter shall be powered from a reliable, local 120VAC source, originating from a designated facility panel.

· Output Signals: The meter's transmitter must provide at a minimum:

· One (1) 4-20mA analog output proportional to the flow rate (GPM).

· One (1) scaled pulse output proportional to total volume (e.g., 1 pulse per 100 gallons).

· SCADA Connection: The analog and pulse output signals shall be wired to the nearest SCADA RTU or control panel for integration into the central system. All wiring shall be installed in conduit per NEC and UFC requirements.

· Local Display: The meter's transmitter shall include an integral digital display showing, at a minimum, the current flow rate and the totalized volume.

5.0 Required

1. Select Meter Manufacturer: Obtain submittals from qualified manufacturers (e.g., Krohne, Badger Meter, McCrometer) for a meter that meets all performance and compliance criteria.

2. Finalize Meter Locations: Identify the precise installation points in the system that will provide the most valuable data for leak detection and operational control, ensuring the straight-pipe requirements can be met.

3. Design Vault and Piping Layout: Develop detailed construction drawings for the meter vault, including the bypass piping, isolation valves, and all dimensional details.

Design Requirements - 15,000-Gallon Welded Steel Tank & Site Work at Pump Station 2

1.0 Introduction & Purpose

This memorandum establishes the basis of design for the new 15,000-gallon potable water storage tank, its engineered foundation, and all associated site piping, security, and appurtenances to be located at Pump Station 2 (PS-2).

The purpose of this installation is to provide buffer storage, ensuring consistent suction pressure for the new booster pump (detailed in a separate memo) which then feeds the main PS-2 system. The design includes extensive bypass capabilities and backflow prevention to ensure operational flexibility and system protection.

2.0 Governing Standards & Codes

The design, fabrication, and construction shall comply with the latest editions of the following primary standards:

· Unified Facilities Criteria (UFC):

· UFC 3-230-01: Water Supply, Treatment, and Distribution.

· UFC 3-301-01: Structural Engineering (for foundation design).

· UFC 3-201-02: Landscape Architecture (for site restoration).

· UFC 4-022-03: Security Fences and Gates.

· American Water Works Association (AWWA):

· AWWA D100: Welded Carbon Steel Tanks for Water Storage (Primary governing standard for the tank).

· AWWA B-Series: For coating systems (e.g., B604 for interior epoxy).

· AWWA C504: Rubber-Seated Butterfly Valves.

· AWWA C511: Reduced-Pressure Principal Backflow Prevention Assembly.

· AWWA C151: Ductile-Iron Pipe and Fittings.

3.0 Design Criteria

3.1 Welded Steel Tank & Foundation

· Tank:

· Capacity: 15,000-gallon nominal capacity.

· Standard: Shop-fabricated, welded carbon steel construction in full compliance with AWWA D100.

· Coatings: Interior shall be an NSF/ANSI 61 certified epoxy system suitable for potable water. The exterior shall receive a multi-coat industrial urethane system for corrosion and UV protection.

· Foundation:

· An engineered reinforced concrete foundation shall be designed per UFC 3-301-01 and ACI 318.

· The design (either a ringwall or solid slab) must be based on a site-specific geotechnical investigation to determine soil bearing capacity, frost depth, and seismic requirements.

· Tank Appurtenances (per AWWA D100):

· Inlet and Outlet pipe connections.

· Overflow pipe with a flap gate and splash pad.

· Shell manway (24-inch minimum).

· Roof manway (30-inch minimum).

· Exterior caged ladder with a lockable security gate.

· Roof safety railing.

· Vent assembly sized for maximum fill/drain rate, with insect screen.

· Level indicator (local float-type and electronic for SCADA).

3.2 Site Security

· Fencing: The entire tank and booster pump station area shall be enclosed by a 8-foot-high chain-link security fence with a top rail and tension wire, compliant with UFC 4-022-03.

· Gate: A commercial-sized sliding or double-swing gate shall be installed to provide access for maintenance vehicles. A sliding gate is preferred. The gate width must accommodate the largest piece of equipment (e.g., a crane or pump truck).

· Please refer to Design Requirements – Security Fencing and Access Gates.

3.3 Site Piping, Valves, and Backflow Prevention

· System Entry/Exit:

· A Reduced-Pressure Principal Backflow Prevention Assembly (RPZ) compliant with AWWA C511 shall be installed at the point of connection from the existing water main.

· A second RPZ assembly shall be installed on the final discharge piping from the booster pump before it connects to the PS-2 system.

· Piping Material: All below-grade process piping shall be Ductile Iron Pipe (DIP), Class 52, Please refer to the Design Requirements 8-inch DIP Waterline design and constr. 3 27 2026.

· Isolation Valves: All isolation valves for the bypass system shall be Rubber-Seated Butterfly Valves per AWWA C504, installed in valve boxes with operating nuts.

· Bypass Configuration: The piping shall be configured to provide maximum operational flexibility, allowing for the following scenarios:

· Normal Operation: example: Flow from the main -to RPZ – to - Tank - to - Booster Pump -Pump Station 2- to - RPZ – to - Waterline going to SOR.

· Tank Bypass: example: Flow from the main – to - RPZ - to Bypass Line -to Booster Pump -to Pump Station 2- to RPZ – to - Waterline going to SOR. (Allows for tank inspection/maintenance).

· Booster Pump Bypass: example: Flow from the main - to - RPZ -to Tank – to - Bypass Line – to - Pump Station 2– to - RPZ – to - Waterline going to SOR. (Maintains supply at system pressure if booster is down).

· Full System Bypass: example: Flow from the main -to RPZ - to Main Bypass Line -to Pump Station 2– to - RPZ – to - Waterline going to SOR. (Takes both the tank and booster pump offline).

· Please see Design Requirements 8-Inch Bypass and Isolation System.

A detailed piping schematic will be developed by the Designer of Record showing the required four (4) or more isolation butterfly valves to achieve this functionality.

4.0 Requirements

1. Conduct Geotechnical Investigation: This is mandatory for the foundation design and must be completed before structural drawings are developed. This Geotechnical Investigation should include all sites requiring these services.

2. Develop Detailed Piping & Instrumentation Diagram (P&ID): Create a formal P&ID to finalize the layout of the bypass valves, backflow preventers, and all connections.

3. Obtain Tank Vendor Shop Drawings: Select a tank manufacturer to provide detailed fabrication drawings for review and coordination with the foundation and piping design.

This memo establishes the comprehensive design basis for the PS2 tank project. The next steps will involve detailed engineering based on these criteria.

Design Requirements: Applicable Codes This document outlines the design requirements, construction standards, and some of the applicable codes for the project.

Part 1: Core Project Design Requirements This section details the specific technical requirements for the major components of the project.

1.1 Waterline System Design Criteria

1.2 Pump Station #2 & SCADA Upgrade Criteria

1.3 Construction & Site Work Requirements

Part 2: Applicable Codes & Standards This section lists the governing documents that must be followed for all design and construction work.

2.1 Core UFC & UFGS Documents

2.2 Key AWWA Standards