ARC Stormwater System Maintenance Requirements

Resource Consents to Divert and Discharge Stormwater are granted by the Auckland Regional Council (ARC) to manage the discharge of stormwater from industrial,

commercial and residential developments, and other activities that create impervious surfaces e.g. roading. Stormwater management is important to provide water quantity and quality control and to protect aquatic ecosystems. Stormwater management devices include sand filters, rain gardens, stormwater ponds and wetlands, swales and filter strips, enviropods, storm filters, rain tanks and infiltration trenches. The resource consent will regulate both the design and the on-going maintenance of the stormwater system. Stormwater discharge consents are generally granted for terms of 20 to 35 years, and must be renewed before they expire to ensure the discharge of stormwater continues to be legally authorised. The ownership of the consent is required to be held by a legal entity for the duration of the consent.

 

Resource consents can be transferred from one party to another. For residential subdivisions the long-term ownership of stormwater discharge consents can be complex, as the site changes from single to multiple ownership as the newly formed lots are sold. As a result, it is common for stormwater discharge consents to

be transferred from a subdivision developer to a newly formed body corporate. Such a transfer can only occur once 75% of the lots have been sold, whereby the body corporate becomes the consent holder and assumes responsibility of the stormwater system including all on-going operation and maintenance of the stormwater devices onsite.

 

When taking over the responsibility of the stormwater discharge consent there are a number of aspects that a body corporate should be aware of, to ensure the transfer process is effective and on-going compliance with all consents conditions is achieved and sustained. Once the consent is transferred the body corporate has liability and responsibility over the stormwater discharge consent to ensure it is in compliance with all consent conditions.

The developer must submit various documents and receive final signoff from the ARC before a body corporate should take over the ownership of a stormwater discharge consent. These documents include an operation and maintenance plan, planting plans and as-built plans. An ARC post-construction site inspection is also required to ensure devices have been built in accordance with the consent conditions before sign-off is provided. As-built plans must be supplied at this post-construction meeting. Once final sign off of the stormwater system has occurred, a body corporate can be confident that the stormwater system has been constructed and is functioning as per consented designs. If final sign off has not been achieved a body corporate could potentially take over an incomplete stormwater system and would be responsible for any works required to bring the stormwater system into compliance with the consent conditions.

An operation and maintenance plan is an important document which stipulates what maintenance is required to ensure the stormwater management system continues to function efficiently and thus, long-term environmental effects are adequately avoided, remedied and mitigated. A body corporate should ensure they have a good understanding of this document. This plan will provide the frequency of inspections, monitoring and clean out. Maintenance checklists should also be provided within this document. The design of the stormwater treatment system should provide access to the stormwater device by vehicle or by foot to

undertake routine maintenance. Once the consent is transferred to a body corporate, it is important to identify who will be responsible for carrying out all maintenance requirements. When allocating this responsibility it should be recognised that some aspects of the maintenance may require specialised skills, equipment or materials.

 

Long-term contracts can be formed with experienced maintenance professionals to undertake routine inspections and maintenance work of the stormwater system for the duration of the consent. A body corporate should recognise that the on-going maintenance of a stormwater system will bring about various costs. Cost will relate to maintenance contracts, repairs and device specific maintenance such as grass cutting or re-vegetation.

 

Given a stormwater system can be handed over to the body corporate before all the lots have been developed, it is important to ensure that any on-going construction sites have managed sediment control practices in place to ensure that the discharge of construction sediment to stormwater devices is avoided. Where such discharges occur, the devices must be cleaned out before the stormwater discharge consent can be considered to be in compliance with the consent conditions.

 

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