2.6 Site Utilities
The A/E will contact the local utility companies and/or other providers to determine the following: interest in providing service to the GSA; proposed rate structures and/or rebates; and system capacities, etc. This information will be compiled on the Site Analysis Data Sheets (see Appendix A: Submission Requirements). GSA will seek to negotiate contracts with the local utility companies and/or other providers to fix rates and establish connection charges.
Location of Aboveground Utility Elements. It is the A/E’s responsibility to ensure that all utility elements, such as electrical transformers, emergency generators, backflow preventers and meters, are located with access convenient to the utility companies and where they can be integrated with the building and landscape design without creating a negative visual image.
Local Water Authority. Regulations of local water authorities must be followed. The service connection between building and public water line will be coordinated with the local water authority. Use monitoring points (including data logging functions) on primary water meters controlled by the Building Automation System (BAS).Where municipal graywater is available, service connections should be coordinated with the local water authority.
Dual Service. For large buildings or campuses, a loop system fed from more than one source must be considered. Some occupancies require dual service for the fire protection systems under the provisions of the national code used.
Locating Water Lines. Water lines shall be located behind curb lines, in unpaved areas if possible, or under sidewalks if not. They shall not be located under foundations and streets, drives, or other areas where access is severely limited.
Fire Protection Water Supplies. A dependable public or private water supply capable of supplying the required fire flow for fire protection shall be provided for all new construction and renovation projects in accordance with the requirements of NFPA 24. See Chapter 7, Fire Protection, for additional information. Special Requirements. The requirements below supersede the requirements of NFPA 24:
- A secondary water supply for high rise buildings shall be provided in seismic zones 2, 3, and 4 by an on-site reservoir supplying fire pumps installed in accordance with NFPA 20. The supply to the fire pump shall include an auxiliary bypass (normally closed) from the municipal water supply. The secondary water supply shall have enough capacity to supply building fire suppression systems for a 30-minute duration in accordance with appropriate NFPA requirements.
- For buildings located in rural areas where established water supply systems for fire fighting are not available; the water supply shall be obtained from a tank, reservoir or other source that can supply a minimum of 10,000 gallons.
Fire Hydrants. Fire hydrants shall be provided for all new construction and renovation projects in accordance with NFPA 24. The local fire department shall be consulted with regard to their specific requirements regarding the locations of fire hydrants and thread types for hydrant outlets.
Local Sewer Authority. The regulations of the local sewer authority should be followed.
Discharge in Remote Rural Areas. In areas where no public sewers exist, septic tanks and leach fields should be used for sewage discharge. Cesspools are not permitted. Septic systems will have additional land area (in accordance with local and State code requirements) for future expansion of the discharge system.
Locating Sewer Pipes. All sewer lines will be located below unpaved areas if at all possible.
Manholes. Pipe runs between manholes should be straight lines.
Manholes must not be located in the main pedestrian route in walkways. The placement of manholes in other pedestrian areas such as plazas and entry courts should be avoided, particularly in the primary traffic routes across plazas and entry courts.
Cleanouts. Cleanouts will be provided on all service lines, approximately 1500 mm (5 feet) away from the building, and at all line bends where manholes are not used.
It is GSA policy to separate storm drains from sanitary sewers within the property limits, even in cities where separate public systems are not yet available. A storm drainage system may consist of an open system of ditches, channels and culverts or of a piped system with inlets and manholes. In most cases building roof drainage will be collected by the plumbing system and discharged into the storm drains; exceptions are small buildings in rural areas where gutters and downspouts may discharge directly onto the adjacent ground surface.
Most storm drainage systems will be designed for a 25-year minimum storm frequency, unless local criteria are more stringent.
Gravity Drainage. Storm drainage systems should always use gravity flow. Piped systems are preferred. In large campus settings, open ditches or paved channels should be avoided as much as possible.
Location of Storm Drainage Pipes. Storm drainage pipes will be located in unpaved areas wherever possible. It is desirable to offset inlets from main trunk lines to prevent clogging.
Rainwater Harvesting. Rainwater harvesting may be considered as an alternative source for such purposes as irrigation, etc. Rainwater harvesting systems must comply with all local codes and standards.