Hi Ricard



We have spoken with our Chief Wastewater Advisor regarding the proposed wastewater storage tanks for 79 Taranaki Street.



The advice given is :

· that the tanks should be underground – and preferably constructed from fibre glass

· discharge should be controlled by an actuated valve for holding – normally open, close based on level in public main

· the valve will be controlled by an ultrasonic and back up level switch – located within a public wastewater manhole

· Proposed to use existing WW MH – WW35568 – highlighted below. This has a calculated invert level of 5.62m MSL – and has an approximate depth of 1.5m. The level and ability to connect by gravity will need to be confirmed.







· An overflow alarm will be required connected to the WWL system and a red flashing light on the side of the building

· All maintenance, repairs and renewal will be the responsibility of the building owners. Manuals, maintenance schedules etc. will need to be produced and made available for the building owners.

· The tanks will need to be located so that access by a sump truck is achievable

· Can it be confirmed that the flow/discharge rates used have come from the Regional Standard for Water Services



Cheers

Sheryl



Sheryl Barker Senior Drainage Engineer - Land Development



Tel +64 4 912 4465 [mobile number]

Private Bag 39804, Wellington Mail Centre 5045
Level 4, IBM House, 25 Victoria Street, Petone, Lower Hutt

www.wellingtonwater.co.nz<http://www.wellingtonwater.co.nz/>

Wellington Water is owned by the Hutt, Porirua, Upper Hutt and Wellington city councils and Greater Wellington Regional Council.
We manage their drinking water, wastewater and stormwater services.