What common substance falls from the sky, flows through our bodies, runs through the soil beneath our feet, collects in puddles, lakes and oceans, and then vaporizes back into the atmosphere in a never-ending cycle?
Water, as it cycles between land, ocean and atmosphere, forms the major link between the terrestrial world and the aquatic world. Water drips off rooftops, flows over roads, off your toothbrush, and down the drain, percolates through the soils of fields and forests and eventually finds its way into rivers, lakes and oceans.
During its journey, water will pick up leaf litter, soil, nutrients, agricultural chemicals and oil from cars, all of which have profound impacts on life in aquatic systems. Water can also be filtered or purified as it percolates through soil. As part of this journey, water passes through a catchment. The catchment is the land bound by hills or mountains from which rainwater flows downward towards a waterway. Catchments are connected from top to bottom, so what happens upstream in a catchment has a large impact further down the catchment. The effects of human activities across a whole catchment, such as pollution, soil erosion and the spread of weeds, can degrade the quality of water and the environment at the bottom of the catchment.
Across New Zealand land use changes have typically resulted in the loss of vegetation along waterways, the realignment of streams, increased sediment and nutrient loading and greater areas of impervious surface resulting in a range of stressors on aquatic and terrestrial environments. The natural physical environment and hydrological processes are increasingly impacted by development, subdivision and some farming practices.
These issues are highly evident in Doubtless Bay, and communities in the Bay face considerable land and water management issues. Land catchment management in Doubtless Bay directly affects the water quality of its streams, rivers, harbour and sea. This can be seen with the siltation of harbours and estuaries and faecal contamination of estuaries and beaches affecting shellfish gathering and swimming. Local observations, including limited local authority water quality testing and anecdotal evidence, suggest a dramatic decline of water quality in the catchment, estuaries and coastal zones of Doubtless Bay. As a result, the Bay’s rivers and coastal areas are intermittently unsafe to gather kai from, source drinking water, or swim in.
Doubtless Bay Community Care for Our Catchment is an integrated catchment management programme. It aims to connect landowners, stakeholders and communities within the catchment so that a unified plan can be formulated to improve the quality of both fresh water and seawater within the Bay area. As part of “future proofing” Doubtless Bay the programme will then support positive action to achieve those improvements. This will engage existing landcare groups, hapu, schools, farmers, businesses and beachcare groups. An ongoing programme of community lead water quality testing has been initiated to gauge levels and sources of contaminants, and the public will be regularly updated on the results.
To run the programme financial support has been received from the Minister for the Environment's Sustainable Management Fund, which is administered by the Ministry for the Environment.
