Greg has worked for over 25 years as an ecological and water quality consultant. He has undertaken major investigations into water quality and surface water ecology in relation to a wide range of activities for local and regional authorities, government departments and private entities throughout New Zealand.

Greg is also an experienced hearings commissioner and has sat on many resource consent and plan change hearings.

He has also presented expert evidence at resource consent and plan change hearings, Environment Court hearings, and several Water Conservation Order and Environmental Protection Authority hearings.