Video monitoring of littoral processes in support of coastal-zone management.

The Bay of Santander is one of the largest on the Cantabrian Coast (North of Spain) and provides a natural shelter from the waves of the Gulf of Biscay. For that reason, the bay has been used as a harbour since the 12th Century. Likewise "El Puntal" Spit is one of the most important urban beaches within the Bay of Santander. The relevance of the beach is not only induced by the recreation activities but for the protective effect of the beach and dune field on the small tourist village of Somo. The evolution of the beach has been controlled by the history of land reclamation inside the Bay of Santander. In the last 200 years, 50% of the original bay area has been reclaimed, thus the tidal prism and the associated currents have been dramatically reduced. This reduction has lead to a narrowing of the tidal discharge channel forming the bay mouth. A major commercial harbour is present or situated inside the bay. Merchant vessels are larger and deeper, thus navigation channel needs have increased in the recent years. Both effects (larger navigation channel requirements and narrowing of the natural bay mouth) are not compatible and, thus, major dredging works are required periodically. Therefore the management of the beach is carried out by different institutions with different needs and objectives, most of activities based on detailed surveying of the beach. Four cameras have been deployed in order to acquire the images of the El Puntal spit evolution. The cameras are located on the roof of one of the most luxury hotels of Santander, Hotel Real, which has a wonderful view of the spit and inner bay of Santander.

Waves data from the National Wave Network and Tidal data from the National Tidal Network were collected for the entire period of the project (until now). Wave buoys are located in Punta della Maestra (30NM north fro the study site) and Ancona (about 75NM from the study site). A comparison analysis was performed and we concluded that the averaged conditions could be representative for the offshore wave conditions of Ravenna. Tide data have been collected in Porto Corsini harbour, very close to the study site. Two-detail bathymetry, with multibeam system, was carried out in June 2002 and in January 2004; Two intensive field campaign to measure waves and currents were carried out in the period Nov 03-Jan 04 and in the period Nov 04 - Jan 05. Two ADCP Sentinel 1200 by RDInstrument were installed during the field campaign. The instruments measure directional waves and velocity components along the vertical profiles. The first ADCP was deployed 20m onshore the LCS gap in 3.5m depth, in order to measure transmitted waves in the protected area (every hour), long-shore currents at the lee side of the barrier and cross-shore currents at the gap. - A data set of 40 shorelines was collected at the beach of Lido di Dante in the period 15-22 July 2004. The shoreline surveys were conducted by moving a GPS in kinematic mode over a distance of about 700 meters alongshore, in the protected area delimitated by the external groins, at the instantaneous centre of the swash zone. In order to estimate the intertidal beach slope everyday of the fieldwork about 60 cross-shore transects were surveyed too. The post processing correction of the single frequency GPS (model SR510 by LEICA geosystems) data through the corrsponding RINEX files of a properly close Continuously Operating Reference Station (CORS) gave out data with centimetre precision.

Development of fully-digital video systems capable of providing high quality data for the monitoring of nearshore coastal zones. Improved system capabilities include better pixel resolution and image quality, increased flexibility as regard to the specification of data collection schemes and lower costs for 2-3 camera stations. The new wystems are presently operational at 3 different monitoring sites in southern Europe.

Initial Report on Coastal State Indicators. This report describes coastal management issues experienced by national-scale coastal managers in Italy, Spain, the Netherlands and the UK. The report addresses the communication problems that are frequently experienced between coastal scientists and managers. The main problem being that the information provided by scientists is often too complex and in an inappropriate form to provide a useful basis for management decisions. These are the results of an initial workshop held in Egmond, NL that was designed to encourage dialog between coastal managers and scientist. The managers were responsible for defining key coastal zone management issues whilst the scientists were charged with offering potential solutions for investigation within the framework of the CoastView project. These solutions were in the form of a simplified set of coastal state indicators that had direct relevance to the fields of navigation, coastal protection, recreation and tourism and ecosystem protection. It is the intention that these coastal state indicators will be derived from coastal video monitoring systems. This is an initial report that will be updated at the end of the CoastView project.

Lido di Dante is a seaside resort located on the Emilia-Romagna coast, 7km from the city of Ravenna, Italy. The use of the beach for tourism, together with its serious erosion problems, started in the 1970's, make the field site interesting for coastal engineering, coastal geomorphology and coastal management studies. The beach of Lido di Dante is located between the Fiumi Uniti river's mouth in the north and Bevano river's mouth in the south. The northern part of the study area is protected by three groins and a parallel semi-submerged breakwater, while the southern part is undefended, therefore the site provides an excellent opportunity to synchronously study the dynamics of the defended and undefended beaches. Of particular interested at Lido di Dante is the comparison between the modifications due to the nearshore hydrodynamics and morphodynamics imposed by the submerged shore-parallel breakwaters as opposed to the hydrodynamics and morphodynamics observed in the unprotected area. The unprotected beach is backed by a dune ridge, on average 2-3 high above Mean Sea Level. The dunes are suffering consistent frontal erosion in the lee of the southernmost groin, while they seem more stable moving away from the structures. They form a continuous ridge down to the Bevano inlet. At this point, the meandering of the river mouth is currently eroding them laterally. The ARGUS station of Lido di Dante has been installed in a natural reserve area, using a wooden tower 18m high. The first camera oriented southwards look at the unprotected beach while the other 3 cameras look at the protected area. The objectives of the project in this site involve Safety & Maintenance beach profile (long term stability of the coast, short term stability of buildings and beach and dunes, stability of defence structures), Recreation & Tourism (space for beach tourism, swimming & swimming hazard, bio-chemical swimming hindrance), Shipping & Navigation (navigation hazards for windsurfs & small sailing boats), Natural Values (quality of the beach in terms of pollution on the beach, density of seaside users, dune ecosystem.)

A three-week field campaign was carried out at Teignmouth, UK in November '02. Field data were collected with the specific aim of testing and validating video-derived parameters (or Coastal State Indicators). These data included: 1) Measurements of the offshore wave spectrum. 2) A full bathymetric survey of the inner and outer estuary. 3) Intertidal beach surveys. 4) Process measurements of wave, currents and sediment transport processes (using 3 rigs that included pressure transducers, electromagnetic current meters and optical backscatter sensors). 5) Rapidly sampled video images (1Hz) A further fieldwork campaign will be carried out in May '03 to complement this work. This will include: 1) Measurement of the lateral flow structure in the channel 2) Stereo video monitoring of the shoreline location 3) A repeat of 1-5 above

A database has been established that includes all the calibrated, pre-processed data collected during the CoastView project. The database includes three primary data types: 1) Image data from the four CoastView video stations at Lido di Dante (Italy), El Puntal (Spain), Egmond (Netherlands) and Teignmouth (UK). 2) Long-term supporting field data including wave, tide and bathymetric survey data for each CoastView field sites. 3) Short-term intensive field campaign data for each of the four CoastView sites. These data were collected specifically to provide validation data for the video derived variables and coastal state indicators under investigation in this study. Full information on the intensive field campaigns is provided under individual sections of this T.I.P. The archive is provided with an html interface which is based on the CoastView website. The archive may be accessed by pressing the Data Archive button on any page of the website. The full data archive including all images has been delivered to the European Commission and exists on the CoastView server. All the image data are available (unrestricted) via the CoastView website. A CD containing all other data is available on request form the project co-ordinator (Dr. Mark Davidson mdavidson@plymouth.ac.uk).

The final report on Coastal State Indicators (CSIs) builds on the work carried out during the first CoastView workshop in Egmond, Netherlands (summarised in the initial report on coastal state indicators). The report details the methodology developed within the CoastView programme for defining useful management CSIs. The report details the background and evolution of the video technology within the timeframe of the CoastView project. Descriptions are given of the demonstration CSIs developed for each of the four CoastView field sites including information on the algorithms and software development for the estimation of video-derived CSIs. Demonstration CSIs pertaining to the coastal management areas of coastal protection, navigation and recreation are covered in the report. Finally, this report summarises potential improvements in the predictive capacity (primarily for coastal evolution) that might be derived from long time-series of high-resolution video data and looks to the future beyond the CoastView project.

A three-week field campaign was carried out on Egmond Beach in October-November 2002. Field data were collected with the specific aim of testing and validating video-derived parameters. These data included: 1) offshore wave data and water levels in the nearshore, 2) 4 full bathymetric surveys of the nearshore zone, 3) 16 full inter-tidal beach surveys with DGPS, 4) process measurements of waves currents and sediment transport processes at 3 fixed stations and 4 removable tripod stations (all stations include electromagnetic current devices, pressure device and optical backscatterance devices), 5) standard ARGUS images and timestack images. Data will be used to validate instantaneous processes and sediment transport and mean water lines etc.

Exploitable results

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