Publications: Research reports and publications

Coastal monitoring using moored platforms: Regional to national considerations

19 November, 2012
Cawthron Report 2199. Prepared for Hawke's Bay Regional Council.

EXECUTIVE SUMMARY

Standardised, long-term datasets on coastal water quality and environmental conditions are critical to assessing and monitoring the health of coastal receiving waters and identifying environmental changes that may be occurring in response to a range of anthropogenic stressors. Largely absent from coastal monitoring programmes in New Zealand is the collection of time-series data for basic water quality variables, such as water temperature, salinity, turbidity, and biological indicators such as dissolved oxygen and chlorophyll-a (proxyfor phytoplankton biomass). These data can be collected efficiently using moored instrumentation capable of transmitting data in real-time to a land-based station.

Hawke's Bay Regional Council (HBRC) is in the process of deploying the Hawke's Bay Water Quality information buoy (HAWQi) that was developed in part through a previous Envirolink project. This Cawthron report builds on this earlier work and aims to: 1) assist in the deployment/placement of HAWQi and the integration of data derived from the buoy with other monitoring data collected by HBRC, and 2) demonstrate how HBRC's regional efforts can be aligned within a national network for widely sharing coastal monitoring data collected by similar platforms across councils. In addition to drawing on international examples, this report incorporates information gathered during discussions at the July 2012 Coastal Special Interest Group (SIG) meeting and responses from a number of councils to questions regarding future implementation and use of moored instrumentation such as HAWQi. Representatives from five regional councils identified over eight important uses for the data collected by coastal monitoring platforms such as HAWQi, including contributions toward State of the Environment (SOE) monitoring, validation and calibration of models, ground truthing remote sensing data, and long-term baseline data for Assessment of EnvironmentalEffects (AEEs) and consent monitoring programmes. In addition to these applications,accessible time-series data collected in 'real-time' can be used to assist in driving models for forecasting water and shellfish quality, monitoring for trends related to climate change, and are also of value to port authorities and recreational ocean users.

HAWQi is ideal for collecting long-term datasets on basic water quality parameters within the 12 mile territorial limit in New Zealand coastal waters and sits nicely between the smaller, nearshore buoys and the much larger coastal alternatives. As part of SOE monitoring in the coastal environment, HBRC currently monitors erosion, ecology, water quality and metal and sediment accumulation. Sampling stations are currently limited to shore side locations; hence, the deployment of HAWQi will extend SOE monitoring into the coastal zone. In the context of developing a regional coastal ocean observation system, HAWQi can serve as a sentinel station and provide long-term data series for the uses identified above. In addition to platforms such as HAWQi, nearshore systems with similar technologies can be periodically deployed and rotated among various locations in order to focus on times and/or areas of interest.