Welcome to kayak fishing! The Porirua area has some great spots for fishing, but water quality can be a concern in certain locations. I would rather avoid Porirua Harbour(the harbour has had issues with pollution in the past, particularly due to stormwater runoff and sewage spills. however, efforts have been made to improve water quality.) and Onepoto Arm(generally more polluted, so it's advisable to avoid fishing here.).

I would choose Pauatahanui Arm(Better water quality compared to Onepoto Arm. It's a popular spot for fishing).

But it's still a good idea to check for any recent water quality reports before heading out