Located on the East Coast of the North Island, Gisborne region covers 8386 square kilometres. Gisborne is known as the city of rivers. The Taruheru and Waimata Rivers join to form the 1200 metre Turanganui River, the shortest river in the country.
Gisborne District Council has 31 stream and river monitoring sites where a range of water quality indicators are tested. Most of these sites are located on Gisborne City rivers and are tested monthly while some sites located on East Coast rivers were tested approximately every second month up until 2015, where testing frequency increased to monthly.
In the rural environment water quality is dominated by production of sediment from the soft rocks (which is accelerated where there is little forest cover), and livestock access to waterways. Unstable hill country makes riparian fencing very difficult.
The district is renowned for soil erosion susceptibility due to historical clearing of indigenous forest from the soft rock hills for pastoral farming.
The main rivers entering Poverty Bay are the Waipaoa River, draining a catchment of approximately 216,000 ha and the Waimata River with a catchment of 37,000 ha.
Further north, the Waiapu catchment of 173,00 ha is the largest and includes the Mata, Waitahia and Tapuaeroa rivers.
Air quality for Gisborne City is represented by the Gisborne Boys High air quality site, which measures air particulate matter. Ambient air quality issues typically occur during colder temperatures in winter due to household fires with the city.
