Lengthy and costly delays may await those who do not have a plan for lawful dewatering of their building sites.
Christchurch's prized water can cause headaches for the excavations essential to the demolition, rebuilding and repair works at the heart of the rebuild. Site dewatering can all too easily breach environmental controls, causing unwelcome costs and delays.
It is all too easy to cause problems unwittingly by intercepting and removing or disposing of water in the wrong place or way, especially as our rivers, streams and aquifers weave an intricate and complex web through and under the city.
Building and demolition sites with excavations readily run the risk of water being intercepted or collected and mixed with mud, cement, oil from machinery or environmentally harmful demolition materials. Such unsavoury cocktails can wreak havoc with the quality of our water resources. Even if the water being discharged is entirely clean, putting too much into small water bodies with low capacity can add to the risk of flooding elsewhere. Important springs or wells can be harmed if their source is intercepted by an excavation.
The RMA requires Environment Canterbury to control the risk of this harm through consent requirements for the taking, diversion and discharge of water, which will capture dewatering. The resulting rules aim to strike a balance between protecting the valuable water resources, while not imposing impractical and unwarranted restrictions:
- Permitted activity rules allow some takes, diversions and discharges for site dewatering without consent, but only if they are unlikely to cause any harm to surface or groundwater. Very specific limits and conditions apply, which are designed specifically to avoid this harm;
- Where the limits or conditions cannot be complied with, other rules require resource consents, so that additional or more specialised protective measures can be required through conditions. If the dewatering is too harmful resource consent can be refused altogether under these rules.
They are far from simple; there are four from two separate regional plans that have to be complied with to avoid needing resource consent. It is not a case of picking the easiest rule and just complying with that either, but all conditions and terms of all rules have to be complied with, from the easiest to the toughest. The conditions impose many limits. For example, on the rate at which water can be pumped, the permitted concentrations of contaminants, the amount that groundwater is allowed to drop when pumping, and the duration of the works (e.g. nine months). Also included are minimum flow rates for streams or rivers into which dewatering fluid is pumped.
If any limits or requirements are breached without resource consent, that is an offence with a maximum fine of $600,000 for companies and $300,000 or two years' imprisonment for individuals. For minor incidents instant fines of $750 or $1000 per day or incident are available.
What is more, ECan also has the power to serve abatement notices requiring that the non-complying dewatering ceases. Breaching one of those is a further offence likely to attract even stiffer fines. You may find that the only way to comply is to get a resource consent, which may require input from an expert planner, hydrologist, ecologist or other type of environmental scientists. These experts could be required to help demonstrate that your dewatering meets the policy requirements also contained in the two regional plans that apply. The application is not a rubber stamping exercise and getting consent may take some time. With a site filling up with water, work has to stop; resulting delays while machinery sits idle are potentially far more costly than the considerable available fines.
Since excavations typically intercept groundwater or collect surface water runoff, having a plan for dewatering lawfully is essential. Before the machinery or contractors are ordered, check whether you can comply with ECan's rules, get the necessary consents if you cannot and implement practical measures to ensure you comply with the permitted activity or resource consent conditions.
Whatever the cost or inconvenience of that, it pales into insignificance when compared to the potential cost of being held up while you get the necessary cost or, or of being convicted and fined for dewatering that breaches the RMA.
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.