Continuous high-frequency monitoring of estuarine water quality as a decision support tool: a Dublin Port case study

High-frequency, continuous monitoring using in situ sensors offers a comprehensive and improved insight into the temporal and spatial variability of any water body. In this paper, we describe a 7-month exploratory monitoring programme in Dublin Port, demonstrating the value of high-frequency data in enhancing knowledge of processes, informing discrete sampling, and ultimately increasing the efficiency of port and environmental management. Kruskal–Wallis and Mann–Whitney tests were used to show that shipping operating in Dublin Port has a small–medium effect on turbidity readings collected by in situ sensors. Turbidity events are largely related to vessel activity in Dublin Port, caused by re-suspension of sediments by vessel propulsion systems. The magnitudes of such events are strongly related to water level and tidal state at vessel arrival times. Crucially, measurements of Escherichia coli and enterococci contamination from discrete samples taken at key periods related to detected turbidity events were up to nine times higher after vessel arrival than prior to disturbance. Daily in situ turbidity patterns revealed time-dependent water quality “hot spots” during a 24-h period. We demonstrate conclusively that if representative environmental assessment of water quality is to be performed at such sites, sampling times, informed by continous monitoring data, should take into account these daily variations. This work outlines the potential of sensor technologies and continuous monitoring, to act as a decision support tool in both environmental and port management.

[1]  Kirk Martinez,et al.  Environmental Sensor Networks: A revolution in the earth system science? , 2006 .

[2]  Ronald L. Ohrel,et al.  Volunteer Estuary Monitoring: A Methods Manual , 2012 .

[3]  D. Goda.  Statistics: A Tool for Social Research , 1992 .

[4]  Kenneth S. Johnson,et al.  The Land/Ocean Biogeochemical Observatory: A robust networked mooring system for continuously monitoring complex biogeochemical cycles in estuaries , 2008 .

[5]  Kim N. Irvine,et al.  Impact of a ship passage on bacteria levels and suspended sediment characteristics in the Buffalo River, New York , 1996 .

[6]  E. Cowling,et al.  Chemical climatology of high elevation spruce-fir forests in the southern Appalachian mountains. , 1992, Environmental pollution.

[7]  Tarmo Soomere,et al.  Fast Ferry Traffic as a Qualitatively New Forcing Factor of Environmental Processes in Non-Tidal Sea Areas: A Case Study in Tallinn Bay, Baltic Sea , 2005 .

[8]  M. Kingsley,et al.  THE EFFECT OF VESSEL NOISE ON THE VOCAL BEHAVIOR OF BELUGAS IN THE ST. LAWRENCE RIVER ESTUARY, CANADA , 1999 .

[9]  Brendan O'Flynn,et al.  DEPLOY: a long term deployment of a water quality sensor monitoring system , 2012 .

[10]  R. Whitman,et al.  Ubiquity and Persistence of Escherichia coli in a Midwestern Coastal Stream , 2003, Applied and Environmental Microbiology.

[11]  Richard J. Wagner,et al.  Guidelines and Standard Procedures for Continuous Water-Quality Monitors: Station Operation, Record Computation, and Data Reporting , 2014 .

[12]  T. Grizzard,et al.  Distribution of polyaromatic hydrocarbons in the water column and sediments of a drinking water reservoir with respect to boating activity , 1994 .

[13]  Stephen C. Riser,et al.  Chemical Sensor Networks for the Aquatic Environment , 2007 .

[14]  D. D. Macdonald,et al.  Effects of Suspended Sediments on Aquatic Ecosystems , 1991 .

[15]  Y. A. Yousef,et al.  Changes in phosphorus concentrations due to mixing by motorboats in shallow lakes , 1980 .

[16]  David H. Schoellhamer,et al.  Anthropogenic Sediment Resuspension Mechanisms in a Shallow Microtidal Estuary , 1996 .

[17]  Y. A. Pachepsky,et al.  Escherichia Coli and Fecal Coliforms in Freshwater and Estuarine Sediments , 2011 .

[18]  A. E. Greenberg,et al.  Standard methods for the examination of water and wastewater : supplement to the sixteenth edition , 1988 .

[19]  Andy Field,et al.  Discovering statistics using SPSS, 2nd ed. , 2005 .

[20]  M. Elliott,et al.  The Need for Definitions in Understanding Estuaries , 2002 .

[21]  P. Holden,et al.  A mechanistic model of runoff-associated fecal coliform fate and transport through a coastal lagoon. , 2003, Water research.

[22]  M. Bruen,et al.  Environmental consequences of a power plant shut-down: a three-dimensional water quality model of Dublin Bay. , 2013, Marine pollution bulletin.

[23]  D. Schoellhamer.  Resuspension of Bottom Sediments, Sedimentation, and Tributary Storm Discharge at Bayboro Harbor and the Port of St. Petersburg, Florida , 1993 .

[24]  N. Iversen,et al.  Relationship Between Fecal Indicators in Sediment and Recreational Waters in a Danish Estuary , 2008 .

[25]  Wayne G. Landis,et al.  Regional Ecological Risk Assessment of a Near Shore Marine Environment: Cherry Point, WA , 2004 .

[26]  J. Burkholder,et al.  Real-time remote monitoring of water quality: a review of current applications, and advancements in sensor, telemetry, and computing technologies , 2004 .

[27]  Brendan O'Flynn,et al.  A demonstration of wireless sensing for long term monitoring of water quality , 2009, 2009 IEEE 34th Conference on Local Computer Networks.

[28]  James G. Wilson,et al.  Productivity, Fisheries and Aquaculture in Temperate Estuaries , 2002 .

[29]  David K. Stevens,et al.  A sensor network for high frequency estimation of water quality constituent fluxes using surrogates , 2010, Environ. Model. Softw..

[30]  J. Boissonnas.  Integrating marine science in Europe , 2002 .

[31]  L. Perelo.  Review: In situ and bioremediation of organic pollutants in aquatic sediments. , 2010, Journal of hazardous materials.

[32]  A. Dennis Lemly,et al.  Effects of Sedimentation and Turbidity on Lotic Food Webs: A Concise Review for Natural Resource Managers , 2000 .

[33]  Michael Bruen,et al.  A Three-Dimensional Hydro-Environmental Model of Dublin Bay , 2011 .

[34]  R. Verneya,et al.  The effect of wave-induced turbulence on intertidal mudflats : Impact of boat traffic and wind , 2007 .

[35]  G. Bryan,et al.  Bioavailability, accumulation and effects of heavy metals in sediments with special reference to United Kingdom estuaries: a review. , 1992, Environmental pollution.

[36]  J. C. Chen,et al.  Environmental fate and chemistry of organic pollutants in the sediment of Xiamen and Victoria Harbours , 1995 .

[37]  Steffen Roth,et al.  Functional analysis by trophic guilds of macrobenthic community structure in Dublin Bay, Ireland , 1998 .

[38]  Pavlos Protopapas,et al.  Event Discovery in Time Series , 2009, SDM.

[39]  Andy P. Field,et al.  Discovering Statistics Using SPSS , 2000 .

[40]  Jussi Meriluoto,et al.  Effects of ship traffic on archipelago waters off the Långnäs harbour in Åland, SW Finland , 2001, Hydrobiologia.