Improving on-site domestic wastewater treatment systems - West Coast Lagoons Project

Transcription

1 Improving on-site domestic wastewater treatment systems - West Coast Lagoons Project West Coast Lagoons Project- Improving Karekare, Piha, North Piha and Te Henga stream water quality Council is offering residents at Karekare, Piha, North Piha and Te Henga a subsidised process to upgrade existing on-site wastewater treatment facilities. Monitoring by Auckland Council shows that many of the streams and lagoons at these west coast beaches are potentially unsafe for water contact recreation. The subsidy scheme is to encourage residents to upgrade their wastewater treatment systems to improve the overall water quality in line with current standards. What are on-site wastewater treatment systems? On-site wastewater treatment systems are generally used on properties that are not connected to sewer mains. On-site wastewater treatment systems are used for the treatment of wastewater from toilets, bathrooms, kitchens and laundry. The effluent is then discharged to ground within the property. Out with the old - Septic tanks/disposal trenches or beds are no longer recommended. Septic tanks are no longer recommended in areas where there is concentrated development, small lot sizes, and sites with constraints such as steeply sloping sites, sites with poorly draining soils or high water tables. It is likely that wastewater from septic tank systems is contributing to the poor water quality in the streams and lagoons. Many older wastewater systems use septic tanks and trenches or beds. Septic tanks are a primary treatment system that involves only the separation of solids and some anaerobic action. Septic tanks provide the simplest form of treatment and rely on the soil to provide a great deal of the final treatment before the wastewater reaches surface or groundwater. These types of systems are mainly suitable for rural areas where lot sizes are large and concerns of surface water and groundwater contamination are low. In with the new Secondary treatment systems to improve water quality To encourage the replacement of existing septic tanks with wastewater treatment systems that produce a better quality effluent (secondary treatment systems), Auckland Council is offering applicants a streamlined and subsidised consenting process. We are offering different process and fee incentives which reflect the environmental benefit the upgraded system provides.

2 Subsidy 1: A conventional septic system or high performance system not OSET NTP tested A building consent will be required A fixed building consent fee of $1000 will apply Where resource consent is required, a fixed fee of $1000 will apply. A maintenance contract is required. Subsidy 2: A Secondary or advance secondary on-site wastewater treatment system tested and certified through OSET NTP A building consent exemption will be granted* The exemption will be processed free of charge Where a resource consent is required, a fixed fee of $1000 will apply See below for specifications of the treatment and disposal system and documentation Subsidy 3: A Tertiary on-site wastewater treatment system tested and certified through OSET NTP A building consent exemption will be granted* The exemption will be processed free of charge Where a resource consent is required, the consent will be processed free of charge See below for specifications of the treatment and disposal system and documentation For information on the wastewater systems tested and certified under the on-site effluent treatment national testing programme (OSET NTP), refer to the Water NZ website. In order to qualify for this incentive scheme, all systems must be designed by a suitably qualified wastewater designer and installed by a certifying drain layer or a certifying plumber. *Note: The subsidy does not apply to enabling works or other improvements required in association with the wastewater treatment system upgrade. For example, where retaining walls to support a treatment system are required, this may require building and or resource consent and may also attract fees in the normal manner.

3 Specifications of treatment and disposal system and documentation requirements To be eligible for the subsidy, your new wastewater treatment system is required to provide a minimum of secondary or advanced secondary wastewater treatment. Subsidy 2: Secondary or advanced secondary on-site wastewater treatment system tested and certified through OSET NTP Technical standards: To be eligible for the Council Subsidy 2 your new treatment and disposal system must comply with: Resource Management Act 1991, the Health Act 1956 and the New Zealand Building Code G13 Foul water and regional rules AS/NZS 1547: 2012 and TP 58 including the water separation distances Tested through the On-Site Effluent Treatment National Testing Programme (OSET NTP) and is capable of meeting the minimum of secondary effluent quality standards Effluent distribution is via pressure compensated drip irrigation (PCDI) unless the existing effluent disposal system has been shown to be suitable for ongoing use Designed and installed by a registered drain layer and ideally should be trained by the manufacturer/supplier Must enter into a maintenance contract with an approved contractor. Documentation required: Completed application form AC2119 (for an exemption to a building consent) Authorisation of agent for obtaining an exemption from building consent Scaled site plans indicating site boundaries, contours, easements, driveways, pools, retaining walls, large trees, disposal field including air valves and flush valve Site & soil evaluation report System design (sizing and application) including Irrigation field layout design, specifications and verification and OSET NTP testing and certification documentation A producer statement design PS1 from a qualified designer verifying the design complies with NZBC/G13& B2 Construction drawings and cross sections of all system components Current performance test certificate or certified approvals Agreement to enter into a maintenance contract with an approved contractor. Where it identified that resource consent is required, standard resource consent application information will be required. This will be discussed at the pre-application meeting. Upon completion of the building work the following documentation will be required to be submitted to Council for record keeping:-

4 Producer statement construction (PS3), to be submitted by a certifying drain layer for the construction of the on-site wastewater treatment and disposal system for compliance with G13 A copy of As-built plumbing and drainage plans Producer statement construction review (PS4) is to be submitted by the Engineer for the observation and construction of the on-site wastewater treatment and disposal system for compliance with G13 A copy of the maintenance agreement for the on-going maintenance of the wastewater treatment and disposal system is also required. Example of a secondary on-site wastewater treatment system (modern septic tank, intermittent sand filter, and drip irrigation field) Subsidy 3: A Tertiary on-site wastewater treatment system tested and certified through OSET NTP Technical standards: In addition to the requirements covered within Subsidy 2, the following must be complied with: The package on-site wastewater treatment plant must be selected from a system that has been tested through the OSET NTP, with test results and certification showing that the specific wastewater treatment system proposed is capable of meeting the minimum effluent quality standards as follows:- o Biochemical oxygen demand 15 mg/l

5 o Total suspended solids 15 mg/l o Faecal coliforms less than 200 CFU or MPN/100ml The method of disinfection utilised is ultra violet disinfection. The effluent is discharged to land using timed dosing (not on demand dosing) Effluent distribution is via pressure compensated drip irrigation (PCDI) unless the existing effluent disposal system has been shown to be suitable for ongoing use. All minimum separation distances to surface water are met as specified by TP58. Documentation required: As per Subsidy 2 In addition to the standard application documentation required, the following must be provided with the application for resource consent: OSET NTP test results and certification for the proposed wastewater treatment plant illustrating compliance with the above quality standards. Subsidy Period This policy will be implemented initially as a trial for a period of one year starting from 17 August 2015 until 30 th of July Consents lodged between those dates will be eligible for the subsidy regardless of approval date and providing the consent application meets the compliance How to apply:- A combined building and planning pre-application meeting with council officers is required to discuss your application. The purpose of the meeting is to clarify whether or not a resource consent is required and to outline the consenting process and any specific You can arrange a pre-application meeting in the Henderson service centre either by phoning or online: spx It is important to follow the advice given at the pre-application stage in order to benefit from the subsidy and capitalise on the streamlined consent process. Note that although the application fee may be reduced or waived for the resource consent, this does not mean that a consent will be granted for the discharge. Auckland Council will assess the application in the same manner as other resource consent applications. Other Fees: For resource consents issued under subsidy 2 and 3, there will not be fees charged for monitoring a compliant site. Where non-compliances to the consent requirements occur which result in additional compliance officer time, costs will be charged in accordance with Section 36 of the Resource Management Act.