1,000 to 30,000 Litre Underground / Above Ground Storage Tank

With Modular Versatility

Environmental Division

Designed and Engineered to AS/NZS Requirements

• AS/NZS 1170 Loading • AS/NZS 4766-2006 Product Specifications • Capable of Above or Below Ground Applications • Storm Water, Grey Water, Sewerage and Potable / Fuel • Suitable to Meet a Wide Range of Requirements

Product and Installation Guide

Detention Tank Specification and

Approved to:

AS/NZS 1170 AS/NZS 4766-2006

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1. Contents

1. Contents................................................................................. 3

2. Introduction............................................................................. 4

3. Key Features.......................................................................... 4

4. Tank Standards...................................................................... 4

5. Design and Tank Requirements............................................. 5

6. Installation.............................................................................. 5

7. Maintenance........................................................................... 6

8. Load Rating Analysis.............................................................. 6

9. Illustrations............................................................................. 7

10. Contact Us.............................................................................. 10

11. Appendix - Engineers Compliance Report........ 11

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1. Introduction

VERSATILITY -“envirogental” Detention Tanks offer versatile options for reducing the flow of storm induced water flows. It is designed for use in industrial, agricultural and residential housing applications. ENGINEERED -The “envirogental” Detention Tank system is a fully engineered and certified modular multi-use underground or aboveground tank. Usable as either a Detention Tank (slow release of water into stormwater drain or other runoff), Retention Tank (for reuse of retained water), Storage or alternatively a combination of the above. EASY MAINTENANCE -The “envirogental” Detention Tank system offers the ability to alleviate blockage problems with a double filter system, the first built for large debris at the inlet point that can be removed, and if required a second simple commercial secondary filter box can be installed on the outlet. A easy-clean sump is incorporated into the base below the inspection riser to further collect debris.

2. Key Features

• Tanks are pre-assembled and ready to install • Unique double filter system and easily removable catch pit filter • Light weight (62kg per module/ 18kgs per riser), easy to install. • Modular 1,000 litre increments • Ideal for hard to access locations • Very easy to maintain and clean with integral inspection riser and sump • Designed for underground use in traffic areas, no special bridge requirements • Moulded-in inlet and outlet pipe options • Multiple inlet and outlet options using UNISEAL® connections

3. Tank Standards

All tanks have been built to the following standards Engineers Summary: • Complies with load testing for light and medium vehicular loading—AS/NZ 1170 1:2002

Table 3.1 • Plastic construction and moulding complies with AS/NZS 4766.2006 specifically for

Polyethylene Storage Tank for water and chemicals.

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5. Design and Tank Requirements We recommend tank sizes and installation specification requirements be specified by an approved person to ensure compliance by the relevant Local Authority regulations. Specific requirements vary between Authorities and may change from time to time. “envirogental” Tanks are produced in 1,000 litre modules and can be installed in any combination of 1,000 litre multiples. The Inlet(s) / Outlet(s) or any other such requirements such as inter-module connections designed can be drilled out and most commercially available seals (eg UNISEAL® outlet / inlet pipe fittings with a sealed backing plate or a spin welded thread applied to the tank can be used. Please Note: PE plastic does not hold glue indefinitely.

6. Installation It is very important the correct installation procedure is followed to ensure the successful performance of “envirogentle” tanks.

1. Prepare founding substrate to receive detention tanks, ensuring good ground with any soft spots removed and replaced with compacted GAP40

2. Provide minimum 150mm layer of well compacted GAP40 hard fill or similar with multiple passes (minimum 20) of a 75kg 300 x 300 hand-operated plate compactor.

3. Provide a minimum 50mm AP7, sand or similar levelling layer over GAP40 layer.

4. Place detention tank in position and level.

5. Compact around and over the tank in 150mm maximum layers of GAP40 hard fill or similar with multiple passes (minimum 20) of a 75kg 300 x 300 hand-operated plate compactor, taking special care to ensure that areas between the tank ‘feet’ are properly compacted.

6. If installed in traffic areas ensure sides and ends of excavation are either solid natural earth or constructed wall a minimum of 200mm from tank wall and the tank top covered with a minimum 300mm compacted as above.

7. Foot traffic installations need only enough cover to suit individual requirements and adequate safe drainage.

8. In areas with a high water table it is recommended that the ‘feet’ be concreted in with a 200mm (including ‘feet’) slab over the ‘feet’ to prevent uplift in the event of empty tanks. An Engineer should be consulted in such cases prior to any installation.

9. It is recommended that a Registered Drain Layer be used to install “envirogentle” tanks.

10. The tank has a UV8—UV20 rating and can be safely installed on a level surface above ground or partially buried.

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7. Maintenance Leaf deflectors should be installed on all downpipes leading into tanks to prevent the build-up of unnecessary debris within the tanks. When operating, detention tanks have the potential to surcharge the private drains that feed into them. Ensure that basement floor levels are at least 300mm above the soffit of the detention tank overflow pipe. Failure to do so could result in basements being flooded via basement drains. Al-ternatively, basement drains should be connected to the drainage system only at point down-stream of the detention tank. All new installations should be inspected and cleaned of sediment and debris from the building

site prior to the issue of a Code of Compliance Certificate. Underground detention tanks may in-

cur sediment and debris build up. To ensure good operation they should be frequently inspected

and cleaned / maintained to an operators recommended schedule.

Ensure the plastic lid or steel grill is used to prevent entry into the riser. Either lid needs to be se-

cured by lock / screws to prevent unauthorised entry.

Frequency of cleanout of the removable catch pit within the tank will be dependent on the volume and frequency of debris entering. It is the responsibility of the person / body responsible for the tank for such maintenance. The removable Filter Bucket is designed to reduce maintenance costs by eliminating the regular need to have the detention tank “pumped” free of silt and debris. Lids of tanks are to be locked / screwed when unattended. It is strongly recommended that entry to and the maintenance and cleaning of the tank is carried out by a professional / plumber/drain layer. Plumber / Professionals: Always have somebody standing guard at the entrance to the tank if en-tering the tank. Do not enter the tank while it is raining or if it is about to rain.

8. Certification and Report

Engineers report and further details are available to certified architects and other authorised bod-ies.

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9. Illustrations

1,000 Ltr Detention Tank & Riser

Lift off Lid

Moveable position 100mm inlet

Multi outlet capable 100mm outlet pipe

5,000 Ltr Detention Tank

5 Modular Units bolted & welded together

1,000 Ltr Detention Tank Module

Bolted and Welded to expand or join by pipe and UNISEAL® seal Feet

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Detention Tank Module Low Profile

Detention Tank

Detention Tank Section View

Primary Filter

Illustrations: 1,000 Ltr Module

Multiple position outlet

Sump

Secondary Filter Option

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9. Illustrations Detention tank parts overview, measurements and specification

Top View

1625

1400

1400

Inlet End View Side View

1625

1200

900

300

600

1400

680

110

Outlet End View

For Architects and Engineers we provide usable drawing files for convenience. For Drawings of DXF and others, please refer to contact details.

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MODULAR DETENTION TANK

7000

TOP VIEW

SIDE VIEW OUTLET VIEW

1400

1725

300

900

525

680

5,000 Ltr Solution

1000L Module

Riser Inlet

Outlet

Sump

TOP VIEW SIDE VIEW

Single 1,000 Ltr Module

1400

1400

1625

600

900

300

1200

1625

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10. Contact Us

Auckland Office

30 Poland Rd, Glenfield

PO Box 33-615, Takapuna

Auckland, New Zealand

Tel 09 443 5880 Fax 09 443 5882

Hamilton Office

297 Kahikatea Drive Extn

PO Box 5194, Frankton

Hamilton, New Zealand

Tel 07 846 0932 Fax 07 846 9210

www.rotationalplastics.co.nz

E-mail: sales@rotationalplastics.co.nz

Other Rotational Plastics NZ Limited Leading Brands:

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11. Appendix: Structural Report for Compliance Load

Testing to AS / NZS1170