Collection and extraction of water level information from a digital river camera image dataset Article Published Version Creative Commons: Attribution 4.0 (CC-BY) Open Access Vetra-Carvalho, S., Dance, S. L. ORCID: https://orcid.org/0000-0003-1690-3338, Mason, D. C., Waller, J. A., Cooper, E. S., Smith, P. J. and Tabeart, J. M. (2020) Collection and extraction of water level information from a digital river camera image dataset. Data In Brief, 33. 106338. ISSN 2352-3409 doi: https://doi.org/10.1016/j.dib.2020.106338 Available at http://centaur.reading.ac.uk/93137/ It is advisable to refer to the publisher’s version if you intend to cite from the work. See Guidance on citing . To link to this article DOI: http://dx.doi.org/10.1016/j.dib.2020.106338 Publisher: Elsevier All outputs in CentAUR are protected by Intellectual Property Rights law, including copyright law. Copyright and IPR is retained by the creators or other copyright holders. Terms and conditions for use of this material are defined in the End User Agreement . www.reading.ac.uk/centaur CentAUR Central Archive at the University of Reading Reading’s research outputs online Data in Brief 33 (2020) 106338 Contents lists available at ScienceDirect Data in Brief journal homepage: www.elsevier.com/locate/dib Data Article Collection and extraction of water level information from a digital river camera image dataset ∗ Sanita Vetra-Carvalho a,1, Sarah L. Dance a,b, , David C. Mason c, Joanne A. Waller a,2, Elizabeth S. Cooper a,3, Polly J. Smith a, Jemima M. Tabeart b,d,4 a Department of Meteorology, University of Reading, Earley Gate, Whiteknights Road, Reading RG6 6ET, United Kingdom b Department of Mathematics and Statistics, University of Reading, Whiteknights, Pepper Lane, Reading RG6 6AX, United Kingdom c Department of Geography and Environmental Science, University of Reading, Russell Building, Whiteknights, Pepper Lane, Reading RG6 6DR, United Kingdom d National Centre for Earth Observation (NCEO), Meteorology Building, University of Reading, Earley Gate, Whiteknights Road, Reading RG6 6ET, United Kingdom a r t i c l e i n f o a b s t r a c t Article history: We present a new water level dataset extracted from im- Received 13 July 2020 ages taken by four Farson Digital Ltd river cameras for a Revised 15 September 2020 Tewkesbury, UK flood event (21st November –5th Decem- Accepted 17 September 2020 ber 2012). This data article presents the new water level Available online 28 September 2020 data together with a description of metadata, data acquisi- tion, and extraction methods. The water level information was extracted from the images using measured points in the ∗ Corresponding author at: Department of Meteorology, University of Reading, Earley Gate, Whiteknights Road, Reading RG6 6ET, United Kingdom. E-mail address: [email protected] (S.L. Dance). Social media: (S. Vetra-Carvalho), (S.L. Dance), (J.A. Waller), (E.S. Cooper), (P.J. Smith), (J.M. Tabeart) 1 Sanita Vetra-Carvalho, Spire Global Ltd, Unit 5A, Sky Park 5, 45 Finnieston Street, Glasgow, G3 8JU, United Kingdom. 2 Joanne A. Waller, MetOffice@Reading, Meteorology Building, University of Reading, Earley Gate, Whiteknights Road, Reading, RG6 6ET, United Kingdom. 3 Elizabeth S. Cooper, UK Centre for Ecology & Hydrology, Maclean Building, Benson Lane, Crowmarsh Gifford, Walling- ford, OX10 8BB, United Kingdom. 4 Jemima M. Tabeart, School of Mathematics, The University of Edinburgh, James Clerk Maxwell Building, Peter Guthrie Tait Road, Edinburgh EH9 3FD, United Kingdom. https://doi.org/10.1016/j.dib.2020.106338 2352-3409/© 2020 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ ) 2 S. Vetra-Carvalho, S.L. Dance and D.C. Mason et al. / Data in Brief 33 (2020) 106338 Keywords: field-of-view of each camera using Leica GNSS and Total Sta- River cameras tion instruments with high spatial accuracy of order of 1 cm. Water level observations We use river gauge data to verify the new dataset. The new Gauge data dataset has a short duration but includes the rising limb, Flooding peak discharge and falling limb of the flood event. It has Inundation potential for verifying future automatic water level extrac- tion methods and for development of automatic flood alert methods and can provide valuable information in data as- similation systems used for improving inundation forecasts. © 2020 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ ) Specifications Table Subject Water Science and Technology Specific subject area Water level measurements in rivers Type of data Table Image Graph Figure Text file How data were River camera images (from which the water-level observations were acquired extracted) were taken by Mobotix M24 Allround outdoor web-camera with 3MP (Mega Pixel) resolution. Location metadata were measured by Leica TS 12 (TS) and Leica CS10/CS15 & GS Sensor instruments (GNSS). Data format Raw Analysed Parameters for data Flood event between 21st November and 5th December 2012 in the collection Tewkesbury, UK area. Description of data New water level data obtained from Farson Digital river cameras at collection four locations in the UK. Data was extracted from images manually by matching geo-referenced GNSS & TS metadata with water line points in the field-of-view of each camera. Data source location City/Town/Region: Evesham (Worcestershire), Tewkesbury (Gloucestershire), Diglis Lock (Worcestershire), Strensham Lock (Worcestershire). Country: United Kingdom Data accessibility Repository name: Mendeley Data Data identification number: DOI: 10.17632/769cyvdznp.1 Direct URL to data: http://dx.doi.org/10.17632/769cyvdznp.1 Value of the Data • The new water level dataset provides a proof-of-concept for the use of river cameras as a new source of information on river levels. This initial dataset can be used to verify and vali- date future automatic water level extraction algorithms from river cameras. • The new water-level dataset is especially useful for case studies on short-term flood haz- ard predictions and longer-term flood risk management and planning. This dataset provides novel, complementary information to existing water-level data from river-gauge and satellite synthetic aperture radar (SAR) data on the Tewkesbury November 2012 flood event. In par- ticular, the dataset provides new information on water-levels on the rising limb of the flood when the river is out-of-bank. • This new dataset provides hourly observations during daylight. Such a temporal observation frequency means that river cameras can capture the crucial rising limb of the flood. Thus, S. Vetra-Carvalho, S.L. Dance and D.C. Mason et al. / Data in Brief 33 (2020) 106338 3 the dataset may be used as a new source of information for use with hydrodynamic flood inundation models for calibration and data assimilation. 1. Data Description New water level observations are derived from four river cameras: Diglis Lock, Tewkesbury, Strensham Lock, and Evesham, located on rivers Avon and Severn in the UK (see Fig. 1 ) and are valid for the period between 21st November and 5th December of 2012 when a major flooding event occurred around the Tewkesbury area. The Tewkesbury 2012 flood event is a well-studied and documented event, with a number of river gauges within the catchment that can be used for validation [ 1 , 2 ]. Rainfall is the main driver of the river level rise and fall; however, river levels can also be affected by other factors, e.g. such as the opening and closing of dams and sluices or debris collecting in culverts [3] . The interested reader can download daily cumulative rainfall data from the UK National River Flow Archive [1] for the following raingauge locations illustrated on Fig. 1: Saxons Lode, Besford Bridge, Harford Hill, Knightsford Bridge, Bredon and Evesham. In addition, there is a series of 7 synthetic aperture radar (SAR) satellite overpasses at approximately 12-h intervals during the event, but none are available on the rising limb of the flood [2] . The new river camera dataset provides hourly daytime water level information on both the River Avon and River Severn for both the rising and falling limb of the flood. Thus, the dataset can be used as an additional source of information for flood event case studies, to verify and Fig. 1. Left panel: Map showing locations of the four Farson Digital Ltd river cameras from which the new water level data was extracted: Diglis Lock (river Severn), Tewkesbury (river Avon), Strensham Lock (river Avon), and Evesham (river Avon). Original terrain image taken from [2] . The vertical and horizontal coordinates are Northing and Easting in m. The small yellow dots show nearest river flow and rainfall gauging stations. Right panel: Map of Europe showing the location of the study area. Grid lines show latitude and longitude in degrees. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) 4 S. Vetra-Carvalho, S.L. Dance and D.C. Mason et al. / Data in Brief 33 (2020) 106338 validate future automatic water level extraction algorithms from river cameras and with hydro- dynamic flood inundation models for calibration and data assimilation [ 2 , 4–10 ]. The water levels for the four river cameras over the period were manually ex- tracted from the archived hourly daylight images using high accuracy field-of-view point measurements for each of the cameras. These were measured using GNSS and Total Station. Details of the GNSS coordinate system at all the camera locations are provided in Table 1 . Table 2 shows the 3 G network base stations used at each river camera location to ensure high accuracy GNSS measurements.