Stormwater

Stormwater is the runoff from rural or urban areas. Fallen rain becomes "rural runoff" in the countryside, and "stormwater" in the towns. Both rural runoff and urban stormwater pick up pollutants along the way and deposit them in river estuaries and at stormwater outlets. While rural runoff pollutants are largely "natural" (like nutrients and bugs from animal manure), dirt and grime from city streets and buildings can be very harmful to the environment.

Stormwater does not go to the sewer. Stormwater is carried through stormwater pipes or channels and discharged into nearby rivers or the sea without any treatment. If it is discharged into a calm environment, like Wellington harbour, then the dirt and debris carried with the stormwater builds up. Even "clean" dirt can be harmful if it builds up in a marine environment because it can smother the sandy seabed. But dirt carried by urban stormwater is not clean. It is generally contaminated with heavy metals picked up along the way from roofs, guttering, and roads, as well as oils and rubbish from roads and industrial yards. The toxic levels of stormwater dirt can be just as bad, or worse, than toxic levels in sewage sludge.

Stormwater discharged to rivers, lakes and artificial watercourses is controlled in the Regional Freshwater Plan. Stormwater discharged to the coastal marine area is controlled in the Regional Coastal Plan. Stormwater discharged to land is controlled in the Regional Plan for Discharges to Land.

Discharges into stormwater drains are also controlled under the Resource Management Act. These discharges are controlled in the Regional Plan for Discharges to Land.

Discharges to the coastal marine area

Rule 53 of the Regional Coastal Plan permits discharges of stormwater to the coastal marine area, provided the discharge complies with conditions stated in the rule.

Outside Areas of Significant Conservation Value, Rule 61of the Regional Coastal Plan requires a coastal permit for stormwater discharges that do not comply with the conditions of Rule 53. This is a discretionary activity.

Within Areas of Significant Conservation Value, Rule 62of the Regional Coastal Plan requires a coastal permit for stormwater discharges that do not comply with the conditions of Rule 53. This is a non-complying activity.

Discharges to fresh water (rivers, lakes and artificial watercourses)

Rule 2 of the Regional Freshwater Plan permits stormwater discharges to surface water provided the discharge complies with conditions stated in the rule.

Rule 3 of the Regional Freshwater Plan requires a discharge permit for stormwater discharges that do no comply with conditions (1) or (2) of Rule 2. This is a controlled activity provided the discharge complies with the standards and terms stated in the rule.

Rule 5 of the Regional Freshwater Plan requires a discharge permit for stormwater discharges that are not allowed by Rule 2, or do not meet the standards of Rule 3. This is a discretionary activity.

Discharges to land

Rule 1 of the Regional Plan for Discharges to Land permits discharges of stormwater into stormwater pipes if the pipe then discharges to surface water. This is because discharges from the pipe into surface water are controlled by Rules 2, 3, and 5 of the Regional Freshwater Plan (see above).

Rule 3 of the Regional Plan for Discharges to Land permits discharges of stormwater to land provided the discharge complies with conditions stated in the rule.

Rule 2 of the Regional Plan for Discharges to Land requires a discharge permit for any stormwater discharge to land that does not comply with Rule 3. This is a discretionary activity.