J-1606001-07 Unidirectional Flushing Plan NAS II.pdf

ATTACHMENT -1606001-07

UNIDIRECTIONAL FLUSHING PLAN NAS II

(*) Reference Section C, Annex 0200000 Management and Administration, Spec Item 2.6.2 Dissemination of Information

This plan outlines the work required to perform the “Unidirectional flushing” at NAS II. This results in water flowing toward the hydrant in only one direction resulting in higher flow velocity, more scouring and better cleaning of the pipes with less water use than the “Conventional flushing” This plan will be implemented once per year.

Safety procedure.

Apply before and during the UDF.

1. Necessary personal protective equipment and the correct tools:

a. Personal Protective Equipment (PPE)

i. Safety shoes

ii. Hard hat

iii. Hearing protection

iv. Safety glasses

v. Protective gloves

vi. Reflective vest (CAT 2)

b. Site Safety Equipment Required

i. Availability of communications (telephone or radio)

2. Employees tasked to complete flushing tasks need be minimum two-person due to the distances between hydrants and valves.

3. At least one crew member should be designated to control traffic while the other crew members are operating the distribution system valves.

4. Traffic signs, cones, flags, and/or vehicles with warning lights should be used as necessary to alert motorists of flushing activities.

5. Brightly colored safety vests shall be worn by all crew members.

6. Keep the public away from flushing activities. Children are often attracted to such activities and should be kept away.

7. Open hydrant valves completely to prevent water from discharging through the barrel drain at pressure.

8. Open and close hydrants slowly to prevent the development of dangerous pressure surges and water-hammer.

9. Use well-restrained energy dissipaters designed to prevent the water pouring out of the valve from damaging government and private property.

10. Discharge flushing water directly into a sanitary or storm sewer whenever possible to avoid flooding streets and underground electrical vaults. If street flooding is unavoidable, use signs, flags, and other warning devices to direct traffic away from the area. Notify Security and Fire Department about the UDF situation.

Unidirectional Flushing (UDF) Plan – NAS II Sigonella

The desired minimum velocity is 6 feet per second. A single 2-1/2 inch outlet should be sufficient for the 6-inch and 8-inch mains. For larger mains, it may be more advantageous to open additional hydrants and open the 4-1/2 inch nozzle.

Utilize pitot gauges with flow diffusers to minimize grounds damage.

Main Size Suggested

Minimum Flow

(in) (gpm) 6 550 8 950 10 1500 12 2100 14 2800

Note: In most cases, customers will not notice any changes to their water delivery during the UDF process, but UEM staff must inform the Fire Department and the sensitive customer (Hospital, school etc.) before to start the UDF.

Flushing Strategy: Loops 1 - 4 are intended to be conducted in one continuous operation. As such, (12) valves will be secured during Loop 1 and will remain closed until the conclusion of Loop 4.

Loop 1: (*) (Total of 12 Valves to Be Secured)

Site Plan “A”

Valve Size Location (mm)

W126B 225 (*) W260B 200 W349B 315 W671B 150 W51B 200 W52B 200 W75B 150

Site Plan “B”

Valve Size Location

(mm)

W674B 200 (*) W138B 200

Site Plan “C”

(mm)

W309B 200 (*) W653B 355 W78B 225

Listed below is the sequence of hydrants to operate. Secure each hydrant before proceeding to the next location. Flow each hydrant until the flowing water clears. Record the approximate minutes of flushing performed at each location.

Sequence Hyd ID Location

1 FH94B (*)

2 FH52B

3 FH47B

4 FH91B

5 FH89B

6 FH88B

At the conclusion of Loop 1, do not reopen any valves as they need to remain secured for Loops 3 and 4.

Loop 2: (*)

Valves to Be Secured:

Valve Size Location (mm)

W53B 150 (*) W656B 150

Listed is the sequence of hydrants to operate. Secure the noted hydrant before proceeding to the next location. Flow each hydrant the flowing water clears. Record the approximate minutes of flushing performed at each location.

1 FH160B (*)

2 FH162B

3 FH172B

4 FH175B

5 FH170B

Valves to Be Reopened:

W53B 150 (*) W656B 150

Unlike Loop 1, reopen the (2) secured Loop 2 valves before proceeding to Loop 3.

Loop 3: (*)

W309B 150 (*)

Listed is the sequence of hydrants to operate. Secure the noted hydrant before proceeding to the next

1 FH85B (*)

2 FH66B

3 FH61B

4 FH63B

Valves to Be Reopened:

W309B 150 (*)

Unlike Loop 1, reopen the secured Loop 3 valve before proceeding to Loop 4.

Loop 4: (*)

Valve Size Location (mm)

W310B 200 (*) W658B 355

Listed is the sequence of hydrants to operate. Secure the noted hydrant before proceeding to the next

1 FH48B (*)

2 FH93B

3 FH65B

4 FH55B

5 FH50B

6 FH51B

7 FH58B

Loop #4 Valves to Be Reopened:

W310B 200 (*) W658B 355

At the conclusion of Loop 4 flushing, reopen the twelve (12) valves securing during Loop 1 (listed below):

Site Plan “A”

W126B 225 (*) W260B 200 W349B 315 W671B 150 W51B 200 W52B 200 W75B 150

Site Plan “B”

W674B 200 (*) W138B 200

Site Plan “C”

W309B 200 (*) W653B 355 W78B 225

Loop 5: (*)

Valve Size Location (mm)

W658B 355 (*) W64B 355 W524B 355 W103B 225 W72B 315 W110B 280 W101B 180

Listed is the sequence of hydrants to operate. Secure the noted hydrant before proceeding to the next

1 FH143B (*)

2 FH70B

3 FH141B

4 FH145B

5 FH156B

6 FH150B

7 FH177B

8 FH155B

9 FH153B

10 FH152B

Valves to be reopened:

W658B 355 (*) W64B 355 W524B 355 W103B 225 W72B 315 W110B 280 W101B 180

Loop 6: (*) Flushing Strategy: Loops 6 and 7 are intended to be conducted in one continuous operation.

W51B 200 (*) W36B 355

Listed is the sequence of hydrants to operate. Secure the noted hydrant before proceeding to the next

1 FH79B (*)

Valves to remain closed for Loop 7:

W36B 355 (*)

Valves to open for Loop 7:

W51B 200 (*)

Loop 7: (*) Additional valves to be secured:

W52B 200 (*)

Listed is the sequence of hydrants to operate. Secure the noted hydrant before proceeding to the next

1 FH76B (*)

W52B 200 (*) W36B 200

Note: If you proceed directly to Loop 8, Valve 36B can remain closed.

Loop 8: (*)

Valve Size Location (mm)

W36B 355 (*) W15B 225 W358B 200 W20B 225 W1B 355

Listed is the sequence of hydrants to operate. Secure the noted hydrant before proceeding to the next

1 FH99B (*)

2 FH100B

3 FH113B

4 FH109B

5 FH106B

6 FH107B

W36B 355 (*) W15B 225 W358B 200 W20B 225 W1B 355

Note: If you proceed directly to Loop 9, Valves 1B, 15B, and 358B can remain closed.

Loop 9: (*)

W15B 225 (*) W358B 200 W4B 280 W1B 355 W2B 355 W140B 200

Listed is the sequence of hydrants to operate. Secure the noted hydrant before proceeding to the next

1 FH111B (*)

2 FH119B

3 FH114B

4 FH115B

W15B 225 (*) W358B 200 W4B 280 W1B 355 W2B 355 W140B 200

Note: If you proceed directly to Loop 9, W140B can remain secured.

Loop 10: (*)

W140B 200 (*) W9B 250 W7B 225

Listed is the sequence of hydrants to operate. Secure the noted hydrant before proceeding to the next

1 FH121B (*)

2 FH110B

3 FH126B

4 FH128B

5 FH129B

6 FH122B

W140B 200 (*) W9B 225 W7B 225

Loop 11: (*)

W38B 225 (*)

Listed is the sequence of hydrants to operate. Secure the noted hydrant before proceeding to the next

1 FH130B (*)

2 FH137B

W38B 225 (*)