Which is typically not a requirement for installing drainage systems in New Zealand?

Sourcing materials locally is typically not a mandatory requirement for installing drainage systems in New Zealand. While using proper materials, employing skilled labor, and maintaining specified gradients are essential factors that ensure the effectiveness and compliance of drainage installations, sourcing materials locally does not have the same level of regulatory importance.

The focus on the quality and suitability of materials used is essential to meet safety and performance standards. Skilled labor is equally crucial to ensure that drainage systems are installed correctly and effectively, adhering to local codes and regulations. Maintaining specified gradients is vital for ensuring proper flow and drainage performance, thus preventing issues like blockages and water pooling. In contrast, the local sourcing of materials is more about economic or environmental preferences rather than a strict requirement under the regulations governing drainage systems.