Addendum No. 1 Wicomico County Purchasing 12 N. Division St. Room B-3 Salisbury, MD 21801 Ph. 4-48-480 Fax 4-334-3130 purchasing@wicomicocounty.org Date: 9/16/1 ADDENDUM # 1 Bid: Irrigation Installation at Billy Gene Jackson Park Questions/ Answers Concerns / Issues: 1. Q: It has been mentioned that the main line be changed from the plan of using 2 ½ pipe to 4 pipe. This is a lot of added expense without any advantages. The design is for 60 gpm, 2 ½ or 3 is adequate enough. A: The main line for the design is designated @ 2. on both the plan and in our material take-off. The flow characteristics in 2. SDR21 @ 60GPM reflect more than adequate volume with acceptable pressure loss. All flows are below the FPS rule. 2. Q: The design/spec is for a Rain Bird 2-wire system that is required to have grounding along the wire path, the design/spec does not show this required grounding. If the grounding is not installed, Rain Bird will not warranty the controller or decoders. The 2-wire system also requires the use of the proper wire splices, which are not mentioned. If the proper splices are not installed, this will create problems. A: While the plan does not call out the specific grounding Our MTO reflects all required & necessary grounding per Rain Bird s specifications. Please have any contractor who is bidding call JDL for proper guidance. 3. Q: The design/spec mentions that all rotors and popups are to be installed on swing pipe. The rotors that are specified are 1 commercial rotors requiring the use of 1 PVC swing joints. A: While the plan does call out swing pipe in the general notes Our MTO reflects all sprinklers be connected with Swing Joints. Please have any contractor who is bidding call us for proper guidance. 1
Addendum No. 1 4. Q: The backflow preventor specified is a 1 ½, which is based on the design flow rate, having 4 pipe involved requires several fittings to make this reduction, this is not typical of these types of installations. A: The backflow preventer specified is a 1. PVB the flow characteristics for this devise reflect < PSI loss @ 60 GPM a larger devise will only add cost to the project. The reduction will be from a 2. mainline not a 4 mainline. Please have any contractor who is bidding call us for proper guidance. I have attached the spec sheet for the PVB specified for review. I mention the above items as concerns, if a bidding contractor that understands the above, enters a bid covering these required items, then his price will be higher. If a contractor enters a bid based on what is shown, pricing will be lower but the issues mentioned will have to be addressed. JDL provided design layout for the project and has prepared a material take-off based on the design and proper installation practices. We will be glad to assist the awarded contractor or any other interested party with materials and installation guidance if they have questions. Please feel free to direct anyone with question to me. If there are any further questions please send them in writing to purchasing@wicomicocounty.org. The questions will then be forwarded to the persons with the expertise for answers. Thank you, Wicomico County Purchasing 2
Model 720A Pressure Vacuum Breaker Assembly Application Designed for installation on irrigation water lines to protect against backsiphonage of contaminated water into the potable water supply. Assembly shall provide protection where a potential health hazard exists. Standards Compliance ASSE Listed 20 IAPMO Listed CSA Certified Approved by the Foundation for Cross-Connection Control and Hydraulic Research at the University of Southern California Materials Main valve body Fasteners Elastomers Polymers Springs Cast Bronze ASTM B84 Stainless Steel, 300 Series Silicone (FDA approved) Buna Nitrile (FDA approved) Polypropylene (FDA approved) Delrin (FDA approved) Stainless Steel, 300 series Features Sizes: 1/2", 3/4", 1", 1 1/4", 1 1/2", 2" Maximum working water pressure PSI Maximum working water temperature 1 F Hydrostatic test pressure 300 PSI End connections threaded ANSI B1.20.1 Options (Suffixes can be combined) - with full port QT ball valves (standard) PF - with Z-Bite push fit connections* (1/2"-1" only) PR - with Z-Press press fit connections* *Fittings ship in box with valve and must be threaded into valve by hand on site. Accessories Repair kit (complete) Water Hammer Arrester (Model 120XL) QT-SET Quick Test Fitting Set D B A C Dimensions & Weights (do not include pkg.)! "! " # $ % # & ' # $ ( # ( # ) # $ # * # +, ) # $ ) # + ( % # $ ) & ' ) # ( * % ', $ ) % + ', $ # * # (, ) & $ # * # # + ) & $ # * # # + %, $ ( * + ) # ( * % ' # % & ', $ ) # - ' ) & $ ( # # ' ), $ ) # % # % & $ ( * ' ) # ( (, * # # $ ), % # # % ' - ' ' $ # * # ( - ' ' $ # * # ( -, # $ ( ' - # ) * ) % + - # # $ % ) + # + # $ % % * ' ' # ' ( ' # ' (, # $ ( ' - # ) * ) % + - % & + # # # $ # * % ( # ' - $ # * # - % ' # # $ # * # - &, # $ ( ' - # ) * ) % * # + ) Zurn Industries, LLC Wilkins 1747 Commerce Way, Paso Robles, CA U.S.A. 93446 Ph. 8-663-9876, Fax 80-238-766 In Canada Zurn Industries Limited 344 Nashua Drive, Mississauga, Ontario L4V 1L2 Ph. 90-40-8272, Fax 90-40-1292 www.zurn.com Rev. C Date: /14 Document No. BF-720A Product No. Model 720A Page 1 of 2
Flow Characteristics. / 0 1 2 3 4 6 7 1 8 0 / 9 4 : 8 ; 1 2 9 < / = = >? / 4 / @ 1 A B : 1 8 C PRESSURE LOSS (PSIG) 0.63 1/2" (1mm) MODEL 720A 1/2", 3/4", 1", 1 1/4", 1 1/2" & 2" (STANDARD & METRIC) 1.26 1.89 3/4" (20mm) 2.2 3.2 0 0 20 30 40 0 1" (2mm) FLOW RATES (l/s) 3.8 60 FLOW RATES (GPM) 2.2.0 7.6.1 12.6 69 1 1/4" (32mm) 1 1/2" (40mm) 2" (0mm) 0 0 40 80 120 160 200 3 PRESSURE LOSS (kpa) Typical Installation Local codes shall govern installation requirements. Unless otherwise specified, the assembly shall be mounted at a minimum of 12" (30mm) above the highest piping or outlet downstream of the device. Install with adequate drain and sufficient side clearance for testing and maintenance. The installation shall be made so that no part of the unit can be submerged. A pressure vacuum breaker cannot be installed where back-pressure could occur or where spillage of water from vent could cause damage. N O P O Q R S T S U V W X Q U Y Z W [ Y \ ] ^ R P Y ^ R P Y _ R ` Y a b S c _ Y Q d e a b S c _ Y Q f ] b S c _ Y Q f a b S c _ Y Q f c g h f f i j f c \ h i i j a j c g h j \ k l f c i a d l f \ j c \ h g f i f d i a f h f j i ] i d \ ] f f c \ h i j j a \ d d ] f f c i h j i \ g k j l a i h a i d g f ] a f k d 12" MIN. ABOVE HIGHEST OUTLET 12" MIN. ABOVE HIGHEST PIPING DIRECTION OF FLOW G M J F G G H D E I J K L L K J D G E DIRECTION OF FLOW D E F G G H D E I J K L L K J D G E Specifications The Pressure Vacuum Breaker shall be ASSE 20 approved, and supplied with full port ball valves. The main body and bonnet shall be bronze (ASTM B84), the loaded-air inlet shall use an silicone elastomer spring and seat disc. The entire assembly shall be accessible for maintenance and testing without removing the device from the line. The Pressure Vacuum Breaker shall be a Zurn Wilkins Model 720A. Zurn Industries, LLC Wilkins 1747 Commerce Way, Paso Robles, CA U.S.A. 93446 Ph. 8-663-9876, Fax 80-238-766 In Canada Zurn Industries Limited 344 Nashua Drive, Mississauga, Ontario L4V 1L2 Ph. 90-40-8272, Fax 90-40-1292 www.zurn.com Page 2 of 2
1 ROTOR PUP-UP SPRINKLER 800 6-1- ELECTRIC REMOTE CONTROL VALVE 2 PEB 6-1- QUICK COUPLING VALVE 3 MODEL 3RC 1-27-04 4 ESP-LXD TWO-WIRE DECODER CONTROLLER 1--11 TWO-WIRE CABLE COMMUNICATION CABLE BLUE SOLENOID WIRE COMMUNICATION CABLE WHITE BLUE SOLENOID WIRE DB SERIES WIRE CONNECTORS DB SERIES WIRE CONNECTORS FD-1 TURF M13011 WHITE SOLENOID (VALVE), MASTER VALVE, OR BOOSTER PUMP / VALVE (MAXIMUM 1) NOTE: 1. MAXIMUM LENGTH OF SECONDARY WIRE PATH (14 AWG) FROM DECODER TO SOLENOID IS 40 FEET. FD-1TURF DECODER WIRING DIAGRAM 11-17- CONNECTING AN LDP-1TURF 6 TO 2-WIRE PATH 11-23- 7 CONTROLLER GROUNDING GRID GROUNDING PLATE DESIGN LAYOUT 6-1- 8 SLEEVING 9 PIPE & WIRE TRENCHING PRESSURE VACUUM BREAKER 1" = 20'-0" 79670 IR-2 Details: ROB CREEGAN 09-1-201 BILLY GENE JACKSON PARK SALISBURY, MD D JOHN EERE LANDSCAPES 1-800-347-4272 http://www.johndeerelandscapes.com