Changes for the. TOHOPEKALIGA WATER AUTHORITY Standards, Specifications and Details

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1 Changes for the 2017 TOHOPEKALIGA WATER AUTHORITY Standards, Specifications and Details The following changes are made to the existing standards and details to clarify or improve existing information. Added or privately maintained systems to Jurisdiction paragraph. Whenever possible, the entire water, reuse and wastewater systems shall be shown on a single Master Plan sheet Master Utility Plans must be accepted by TWA prior to construction plan acceptance. Added and sizes to what master plan sheets shall include Added Elevations of wet well lid and all fence corners to what is required in plan and profile sheets Added the Underground Utility contractor to who shall attend preconstruction meeting If project is requesting a phasing plan, the preconstruction meeting is the last opportunity to request to phase utilities for a project v.-Added and witnessed by TWA inspector: vii-added conforms to TWA private lift station policy viii-Added that conform to TWA requirements Added Low air pressure tests and video inspection of lines shall not be performed until sub-base or 10 of cover is over the main and laterals are in to grade at the ROW line Added...or connected to TWA shall be designed Added and accepted by TWA Engineering Division Require the Engineer of Record and Underground Utility Contractor to attend the preconstruction meeting v.-Added and witnessed by TWA inspector vii-added conforms to TWA private lift station policy viii-Added that conform to TWA requirements Added Low air pressure tests and video inspection of lines shall not be performed until sub-base or 10 of cover is over the main and laterals are in to grade at the ROW line (9)-Added Sleeves and casing pipes shall be shown including locations, elevations, length, size and type of pipe material Added walls to list of things gravity sewer shall not be placed along Added with root ball placed within 5 horizontal feet to section on planting distances from TWA owned sanitary sewer mains.

2 Added back the following table that was inadvertently removed in previous edition: Minimum Slope in Feet; pipe diameter greater than 8 inches Sewer Size Per 100 Feet 10 inch inch inch inch inch inch inch inch inch Added elevator sumps to list of items that shall not connect to gravity sewer system Added The flow channel through manholes shall be made to conform in shape and slope to that of the gravity sewers. Flow direction changes in excess of 90 degrees shall not be included in gravity sewer alignments. A flow line elevation drop of 0.1 to 0.2 feet across all manholes shall be provided. Benching shall be provided per the STANDARD CONSTRUCTION DETAIL, TWA-07 and TWA-08, Standard Manhole Detail and Miscellaneous Manhole Detail. At all changes in pipe sizes, the crown elevations of the pipes shall match. Where an unavoidable conflict requires the difference in elevation between the incoming SEWER invert and the outgoing invert to be less than 24, the manhole invert shall be filleted to prevent solids deposition. Where an unavoidable conflict requires the difference in elevation between the incoming SEWER invert and the outgoing invert to be more than 24, an internal drop connection per the STANDARD CONSTRUCTION DETAIL TWA-09, Drop / Force Main Connection to Manhole shall be provided Added On existing manholes only Added Locator balls are required at the wye, 45-degree bend and each cleanout for all sanitary sewer laterals Added walls on list of items FM s cannot be placed within Eliminate sentence requiring TWA approved liner as wet well will require crystalline ad-mixture Add New concrete structures shall contain a crystalline waterproofing concrete admix for ALL new concrete structures including but not limited to manholes, wetwells and wetwell top slabs. Crystalline Waterproofing Concrete Admix shall be added to the concrete during the batching operation. Admix concentration shall be added based upon manufacturer design percent concentration of admixture to the required weight of cement. The amount of cement shall remain the same and not

3 be reduced. A colorant shall be added to verify the admix was added to the concrete for all precast structures. Colorant shall be added and provided at the admix manufacturing facility, not at the concrete batch plant. It is recommended that the admix be added first to the rock and sand and blended thoroughly before adding cement and water or per the manufacturers recommendations. Concrete structures without crystalline waterproofing admix or admix without colorant for field verification shall be rejected Change meter building requirements per new standard details. Meters to be purchased and built by contractor and inspected by TWA like all other pipe and appurtenances Remove master meter delivery section Change meter building requirements per new standard details. Meters to be purchased and built by contractor and inspected by TWA like all other pipe and appurtenances Remove master meter delivery section change single family home to all new residential projects Add Steel casings shall be accurately included on record drawings Add and after installation prior to backfill being placed Add TWA shall require a minimum of one (1) each of 8 gauge steel core and 8 gauge solid copper wire be pulled with each directional bore Add Locator balls are required at wye, 45-degree bend and cleanout for all sanitary sewer laterals Add Service lines not installed and tested in conjunction with a main line in excess of 20 or placed under pavement shall be pressure tested for a minimum 15 minutes at 150 psi with no allowable loss. Water services in excess of 20 shall be disinfected prior to meter installation Add Pre-cast manholes shall be constructed with a pre-cast monolithic base structure as shown on the STANDARD DETAILS. The minimum base thickness shall be eight inches. Concrete for manholes shall be Type II, 4000 psi at 28 days. Barrel, top and base sections shall have tongue and groove joints. All jointing material shall be a cold adhesive preformed plastic gasket, conforming to ASTM C 443 Manhole Section Connections. Manholes shall be leak-free. Sections shall be cured by an approved method as per ASTM C 478 for at least 28 days prior and shall not be shipped until at least two days after having been coated. New concrete structures shall contain a crystalline waterproofing concrete admix for ALL new concrete structures including but not limited to manholes, wetwells and wetwell top slabs. Crystalline Waterproofing Concrete Admix shall be added to the concrete during the batching operation. Admix concentration shall be added based upon manufacturer design percent concentration of admixture to the required weight of cement. The amount of cement shall remain the same and not be reduced. A colorant shall be added to verify the admix was added to the

4 concrete for all precast structures. Colorant shall be added and provided at the admix manufacturing facility, not at the concrete batch plant. It is recommended that the admix be added first to the rock and sand and blended thoroughly before adding cement and water or per the manufacturers recommendations. Concrete structures without crystalline waterproofing admix or admix without colorant for field verification shall be rejected. CONTRACTOR shall provide certification from the pre-caster that the admix was installed in accordance with the manufacturers recommendations. The date of manufacture and the name or trademark of the manufacturer shall be clearly marked on each pre-cast section after coating on exterior surface. Pre-cast concrete top slabs shall be used where cover over the top of the pipe is less than four feet. Lift rings or nonpenetrating lift holes shall be provided for handling pre-cast manhole sections. Existing manholes shall be coated or lined to resist corrosion from a sanitary sewer environment. Coatings or liners shall be applied in strict accordance with the coating or liner manufacturer s recommendations Add The top of buried manholes, cone, riser rings, iron frame, cover and all joints shall be encapsulated with a heat shrink-wrap with a minimum thickness of 98 mils (2.5mm). The wrap shall have a crosslinked polyolefin backing coated with a protective heat activated adhesive. The wrap should effectively bond to the substrate via primer provided by the manufacturer, providing corrosion and moisture protection. The wrap shall be applied with a high intensity propane torch. Heat Shrink wrap for all barrel section joints of manholes shall be a minimum 9-inch width wrap and a minimum of 12-inch width wrap on the corbel section, riser rings and ring & cover. Adhesive tape materials shall not be allowed Remove coatings for all new manholes inside and out Remove coating and liner requirements for new drop or FM connections in manholes Cleaning requirement is at time of final inspection not connection to TWA system Leakage tests shall be for seven (7) minutes with no allowable loss Add Low air pressure tests and video inspection of lines shall not be performed until sub-base or 10 of cover is over the main and laterals are in to grade at the ROW line Remove section on coating and lining for DIP installed underground. TWA does not allow DIP on FM below ground Change to read, A sliding guide bracket shall be an integral part of the pump casing and shall have a machined connecting flange to connect with the cast iron discharge connection, which shall be bolted to the floor of the wet well with 300 series stainless steel anchor bolts and so designed as to receive the pump discharge flange without the need of any bolts or nuts. Sealing of the pumps to the discharge connection shall be accomplished by a simple linear downward motion of the pump with the entire weight of the pumping unit guided by no less than two (2) 300 series

5 seamless 2 minimum tubular stainless steel guides which shall press it tightly against the discharge connection. No portion of the pump shall bear directly on the floor of the wet well and no rotary motion of the pump shall be required for sealing. Sealing at the discharge connection by means of a diaphragm or similar method of sealing shall not be approved as an equal to a metal to metal contact of the pump discharge and mating discharge connection specified and required. Approved pump manufacturers, if necessary to meet the above specification, shall provide a sliding guide bracket adapter. The design shall be such that the pumps shall be automatically connected to the discharge piping Add All service lines shall be wrapped with tracer wire extending a minimum of 12 beyond the curb stop Add Wall penetrations shall be made with watertight gaskets. #57 stone shall be placed below meter vault a minimum of 6 deep and extending 6 beyond the vault in each direction. Bottom of vault shall have a minimum of four (4) ½ weep holes in the bottom. Vault shall be wrapped in filter fabric Add All service lines shall be wrapped with tracer wire extending a minimum of 12 beyond the curb stop Remove Debris cap requirement. DETAILS All details have new notes & requirements DETAILS-2 new details added.