Division 13-09-007
Reclaimed Wastewater System Design
Sections:
13-09-007-0001 Guide for Design
13-09-007-0002 Valve Locations
13-09-007-0003 Reclaimed Wastewater Services
13-09-007-0004 Thrust Block Design
13-09-007-0005 Pumping Stations and Reservoirs
13-09-007-0006 City Participation in Reclaimed Wastewater Line Extensions
13-09-007-0007 Reclaimed Wastewater Line Materials and Construction
13-09-007-0007.1 General Requirements
13-09-007-0008 PVC Pipe for Reclaimed Wastewater Lines
13-09-007-0001 Guide for Design
Reclaimed water shall be used for nonpotable applications such as irrigation, dust control, construction water. It shall not be used as potable water applications including fire protection and buildings. The City of Flagstaff reclaimed wastewater distribution system is designed to provide pressure to certain irrigation users at the same level of service as the City’s Zone B domestic water system. Prior to designing a system for reclaimed wastewater, the prospective user’s project requires review by the City of Flagstaff Water Commission and approval of a user agreement by the City Council. (Ord. 2017-22, Rep&ReEn, 07/05/2017)
13-09-007-0002 Valve Locations
A. It is necessary to be able to isolate sections of reclaimed wastewater piping for repairs while still having the ability to supply reclaimed wastewater to other customers. The location of valves and the number of valves shall be based on the location of customers and the amount of piping that requires dewatering for necessary repairs.
B. Valves shall be generally located as follows, unless otherwise approved by the Utilities Department:
1. At intervals to isolate no more than two (2) fire hydrants at any time.
2. In residential areas to isolate a maximum of thirty (30) services (approximately six hundred (600) feet).
3. At minimum intervals of eight hundred (800) feet.
4. Valves shall not be located in street gutters, valley gutters, concrete aprons, or in driveways.
5. Three (3) valves are required on a four (4) way cross, one (1) valve minimum is required on all three (3) way tee fittings.
C. The valve location is to be a minimum of ten (10) feet upstream of the cap or blowoff assembly. (Ord. 2017-22, Rep&ReEn, 07/05/2017)
13-09-007-0003 Reclaimed Wastewater Services
Acceptable materials for reclaimed wastewater services shall meet those requirements specified for water services. All reclaimed wastewater services shall be identified with warning tape in accordance with Section 13-09-001-0002. (Ord. 2017-22, Rep&ReEn, 07/05/2017)
13-09-007-0004 Thrust Block Design
Engineer’s design must fit main size, design, and soil conditions. (Ord. 2017-22, Rep&ReEn, 07/05/2017)
13-09-007-0005 Pumping Stations and Reservoirs
A. Pump stations, reservoirs, or both, may be required to supply adequate working pressure for applications above the seven thousand (7,000) foot elevation contour. Decisions as to whether such systems can be added to the City system are made by the City Council based on recommendations of the Utilities Director, the City Engineer and the Water Commission.
B. Pump stations are to be designed to meet all minimum requirements of flow in the network with any one (1) of the pumps out of service. (Ord. 2017-22, Rep&ReEn, 07/05/2017)
13-09-007-0006 City Participation in Reclaimed Wastewater Line Extensions
The City encourages the use of reclaimed wastewater for irrigation of large projects. As such, the City may agree to reimburse the user of reclaimed wastewater the cost incurred of extending a reclaimed wastewater line and connecting the service in accordance with a user agreement that has been reviewed by the City Water Commission and approved by the City Council. The amount of reclaimed wastewater used shall be a factor in determining whether the City participates in the line extension. (Ord. 2017-22, Rep&ReEn, 07/05/2017)
13-09-007-0007 Reclaimed Wastewater Line Materials and Construction
New reclaimed wastewater lines may be constructed using the same materials as those specified in these construction standards for new public water lines. (Ord. 2017-22, Rep&ReEn, 07/05/2017)
13-09-007-0007.1 General Requirements
See construction of public water lines. (Ord. 2017-22, Rep&ReEn, 07/05/2017)
13-09-007-0008 PVC Pipe for Reclaimed Wastewater Lines
All PVC pipe requirements for reclaimed wastewater lines shall comply with those set forth in these construction standards for water lines except for the disinfection requirement. (Ord. 2017-22, Rep&ReEn, 07/05/2017)