On the status and mechanisms of coastal erosion in Marawila Beach, Sri Lanka


Coastal erosion remains a problem in many developing countries because of a limited understating of erosion mechanisms and management. Sri Lanka is one of the countries that recognized coastal erosion management as a governmental responsibility, in 1984. Nevertheless, erosion mechanisms have not yet been fully understood. We investigate the status and mechanisms of coastal erosion using empirically collected data and various techniques, such as Geographic Information System analysis of satellite images, drone mapping, bathymetric surveys, hindcasting of wind-induced wave climate, questionnaires, and semi-structured interview surveys. We identified wave climate change, reduction in river sand supply, interruptions from previous erosion management measures, and offshore sand mining as potential causes of erosion considering sediment flux and rates of erosion. Erosion of Marawila Beach began during 2005–2010 and has been continuing ever since, due to a lack of integration in the beach and the entire sediment system. It is necessary to identify the long-term, large-scale changes in the sediment system through data collection. This study highlights the importance of an integrated coastal erosion management plan and could facilitate better coastal erosion management in Sri Lanka, as well as in other developing countries.

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Fig. 1

Source: Google Earth, Data SIO, NOAA, U.S. Navy, NGA, GEBCO (Photograph was taken by CNES-Airbus/DigitalGlobe satellites in December 23, 2017)

Fig. 2

Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community)

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Source: Google Earth, Data SIO, NOAA, U.S. Navy, NGA, GEBCO) (Image was taken by DigitalGlobe). b Shoreline accretion rate from January 2017 to August 2017. c Shoreline accretion rate from August 2017 to February 2018. d Shoreline accretion rate from January 2017 to February 2018. e Significant management initiatives that took place in 2018

Fig. 7

Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community)

Fig. 8

Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community)

Fig. 9

Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community)

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Source: Google Earth, Data SIO, NOAA, U.S. Navy, NGA, GEBCO) (Image was taken by DigitalGlobe); b total sediment accretion between the Maha River mouth and Marawila during December 2001 to May 2017; c cumulative accretion between the Maha River mouth and MB from December 2001 to May 2019

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  1. Aedla R, Dwarakish GS, Reddy DV (2015) Automatic shoreline detection and change detection analysis of netravati-gurpur rivermouth using histogram equalization and adaptive thresholding techniques. Aquat Procedia 4:563–570. https://doi.org/10.1016/j.aqpro.2015.02.073

    Article  Google Scholar 

  2. Bamunawala RMJ, Hettiarachchi SSL, Samarawickrama SP et al (2015) Climate change impacts on seasonal wave climate of the Western Coast of Sri Lanka. ACEPS 2015:126

    Google Scholar 

  3. CC&CRMD (2006) Coastal Zone Management Plan (CZMP) 2004. In: Gaz. extraordinary Part I Sec Gaz. Extraordinary Democr. Social. Repub. Sri Lanka 2006. https://www.coastal.gov.lk/downloads/pdf/CZMPEnglish.pdf. Accessed 9 Oct 2017

  4. CECB (2015) Proposed Colombo port city development project, Colombo, Sri Lanka Supplementary Environmental Impact. Colombo,Sri Lanka, pp 12–16

  5. Chawla A, Tolman HL (2007) Automated grid generation for WAVEWATCH III, pp 71 https://polar.ncep.noaa.gov/mmab/papers/tn254/MMAB_254.pdf. Accessed 18 Dec 2018

  6. Chiang YC, Fang HM, Hsiao SS, Wang HY (2017) Approaching Taiwan’s coastal management problems from the perspective of Toucheng Beach’s disappearance. Ocean Coast Manag 146:170–177. https://doi.org/10.1016/j.ocecoaman.2017.07.004

    Article  Google Scholar 

  7. Dayananda HV (1992) Shoreline erosion in Sri Lanka’s Coastal areas. coast conservation department, Colombo,Sri Lanka, pp 25–42

  8. Fernando KMFS (2005) Maha Oya (river) & river basin from the national deinking water and sanitation service providers' perspective. PowerPoint presentation, The 2nd training course (Sri Lanka) of NARBO (Network of Asia River Basin Organization). Colombo, Sri Lanka

  9. Fernando MSN (2009) Application of mathematical modelling for predicting coastal evolution. Dissertation,The University of Moratuwa, Sri Lanka

  10. Fittschen T, Perera JASC, Scheffer H (1992) Sediment transport study for the Southwest Coast of Sri Lanka. Colombo, Sri Lanka

    Google Scholar 

  11. Gari SR, Newton A, Icely JD (2015) A review of the application and evolution of the DPSIR framework with an emphasis on coastal social-ecological systems. Ocean Coast Manag 103:63–77. https://doi.org/10.1016/j.ocecoaman.2014.11.013

    Article  Google Scholar 

  12. Godage D (1992) Coast erosion management plan and it’s implementation. In: Scheffer H (ed) Seminar on causes of coastal erosion in Sri Lanka. CCD/GTZ coast conservation project, Colombo, Sri Lanka, pp 323–330

    Google Scholar 

  13. Gunaratna PP, Ranasinghe DPL, Sugandika TAN (2011) Assessment of nearshore wave climate off the Southern Coast of Sri Lanka. Engineer 44:33–42. https://doi.org/10.4038/engineer.v44i2.7021

    Article  Google Scholar 

  14. Hager WH (1987) Lateral outflow over side weirs. J Hydraul Eng 113:491–504

    Article  Google Scholar 

  15. Jonah FE (2015) Managing coastal erosion hotspots along the Elmina, Cape Coast and Moree area of Ghana. Ocean Coast Manag 109:9–16. https://doi.org/10.1016/j.ocecoaman.2015.02.007

    Article  Google Scholar 

  16. Kalnay E, Kanamitsu M, Kistler R et al (1996) The NCEP/NCAR 40-year reanalysis project. Bull Am Meteorol Soc 77:437–472

    Article  Google Scholar 

  17. Kamaladasa B (2008) Issues and challenges in river management due to excessive sand mining. In: River Symposium—international water centre. Melbourne, Australia, p 11

  18. Karunaratne W (2011) Impacts of sand and clay mining on the riverine and coastal ecosystems of the Maha Oya : legal and policy issues and recommendations. Colombo, Sri Lanka, pp 11–12

  19. Lloyd MG, Peel D, Duck RW (2013) Towards a social–ecological resilience framework for coastal planning. Land Use Policy 30:925–933. https://doi.org/10.1016/j.landusepol.2012.06.012

    Article  Google Scholar 

  20. Luijendijk A, Hagenaars G, Ranasinghe R et al (2018) The state of the world’s beaches. Sci Rep 8(6641):1–11. https://doi.org/10.1038/s41598-018-24630-6

    Article  Google Scholar 

  21. McCreary S, Gamman J, Brooks B et al (2001) Applying a mediated negotiation framework to integrated coastal zone management. Coast Manag [previously Coast Zo Manag J] 29:183–216. https://doi.org/10.1080/08920750152102035

    Article  Google Scholar 

  22. MMDE (2018) Annual performance report accounts 2017. Colombo,Sri Lanka, pp 40 https://www.parliament.lk/uploads/documents/paperspresented/performance-report-ministry-of-mahaweli-development-environment-2017.pdf. Accessed 10 Oct 2010

  23. NARA (2007) CCD-ChilawBathymetry [.dwg file]. Colombo: CC & CRMD. Available at Chief Engineer's Office (Coastal Development), Coast Conservation & Coastal Resource Management Department, Colombo, Sri Lanka. Accessed 2017 Feb 23

  24. Ndour A, Laïbi RA, Sadio M et al (2018) Management strategies for coastal erosion problems in west Africa: analysis, issues, and constraints drawn from the examples of Senegal and Benin. Ocean Coast Manag 156:92–106. https://doi.org/10.1016/j.ocecoaman.2017.09.001

    Article  Google Scholar 

  25. NGDC (2006) 2-minute gridded global relief data (ETOPO2) v2. doi:https://doi.org/10.7289/V5J1012Q

  26. Oertel GF (2005) Coasts, coastlines, shores, and shorelines. In: Schwartz ML (ed) Encyclopedia of coastal science. Springer, Netherlands, pp 323–327

    Google Scholar 

  27. Perera HN (1990) Need for review and upgrading of master plan for coast erosion management. In: Sheffer HJ (ed) Seminar on causes of coastal erosion in Sri Lanka. CCD/GTZ coast conservation project, Colombo, pp 331–348

    Google Scholar 

  28. Pit IR, Griffioen J, Wassen MJ (2017) Environmental geochemistry of a mega beach nourishment in the Netherlands: Monitoring freshening and oxidation processes. Appl Geochem 80:72–89. https://doi.org/10.1016/j.apgeochem.2017.02.003

    Article  Google Scholar 

  29. Pranzini E (2018) Shore protection in Italy: From hard to soft engineering … and back. Ocean Coast Manag 156:43–57. https://doi.org/10.1016/j.ocecoaman.2017.04.018

    Article  Google Scholar 

  30. Ranasinghe I, Banda RMR (1992) Monitoring resource utilization and their impacts in the coastal zone. In: Scheffer HJ (ed) Seminar on causes of coastal erosion in Sri Lanka. Colombo,Sri Lanka, pp 269–288

  31. Rangel-Buitrago N, Williams AT, Anfuso G (2018) Hard protection structures as a principal coastal erosion management strategy along the Caribbean coast of Colombia. A chronicle of pitfalls. Ocean Coast Manag 156:58–75. https://doi.org/10.1016/j.ocecoaman.2017.04.006

    Article  Google Scholar 

  32. Saengsupavanich C (2013) Detached breakwaters: communities’ preferences for sustainable coastal protection. J Environ Manag 115:106–113. https://doi.org/10.1016/j.jenvman.2012.11.029

    Article  Google Scholar 

  33. Saengsupavanich C, Chonwattana S, Naimsampao T (2009) Coastal erosion through integrated management: a case of Southern Thailand. Ocean Coast Manag 52:307–316. https://doi.org/10.1016/j.ocecoaman.2009.03.005

    Article  Google Scholar 

  34. Samarasekara RSM, Sasaki J, Jayaratne R et al (2018) Historical changes in the shoreline and management of Marawila Beach, Sri Lanka, from 1980 to 2017. Ocean Coast Manag 165:370–384. https://doi.org/10.1016/j.ocecoaman.2018.09.012

    Article  Google Scholar 

  35. Samarasekara RSM (2019) Evaluation of coastal erosion processes and management in a developing country: a case study in Marawila Beach, Sri Lanka. Ph.D. Dissertation, The University of Tokyo, Japan

  36. Samarawikrama SP, Costa WAJ, Dissanayaka DMB, Dulshan PR (2009) Coastal erosion management in Sri Lanka. Dissertation, University of Moratuwa, Sri Lanka

  37. Schmidt L, Gomes C, Guerreiro S, O’Riordan T (2014) Are we all on the same boat? The challenge of adaptation facing Portuguese coastal communities: risk perception, trust-building and genuine participation. Land Use Policy 38:355–365. https://doi.org/10.1016/j.landusepol.2013.11.008

    Article  Google Scholar 

  38. Thevasiyani T, Perera K (2014) Statistical analysis of extreme ocean waves in Galle, Sri Lanka. Weather Clim Extremes 5:40–47

    Article  Google Scholar 

  39. Tolman HL (2009) User manual and system documentation of WAVEWATCH III TM version 3.14. Tech note, MMAB Contrib 276:220 https://polar.ncep.noaa.gov/mmab/papers/tn254/MMAB_254.pdf. Accessed 18 Dec 2018

  40. Van Rijn LC (2003) Longshore sand transport. In: Coastal engineering 2002: solving coastal conundrums. World Scientific, Singapor, pp 2439–2451

  41. Van Rijn LC (2013) Simple general formulae for sand transport in rivers, estuaries and coastal waters. pp 1–16. https://www.leovanrijn-sediment.com/papers/Formulaesandtransport.pdf. Accessed 4 Jul 2019

  42. White A, Deguit E, Jatulan W, Eisma-Osorio L (2006) Integrated coastal management in Philippine local governance: evolution and benefits. Coast Manag 34:287–302. https://doi.org/10.1080/08920750600686687

    Article  Google Scholar 

  43. Wickramaarachchi B (2011) Spatial analysis & mapping. Maha Oya Lowland Corridor. Colombo, Sri Lanka, pp 16–17

    Google Scholar 

  44. Williams AT, Rangel-Buitrago N, Pranzini E, Anfuso G (2018) The management of coastal erosion. Ocean Coast Manag 156:4–20. https://doi.org/10.1016/j.ocecoaman.2017.03.022

    Article  Google Scholar 

  45. Yin P, Duan X, Gao F et al (2019) Coastal erosion in Shandong of China: status and protection challenges. China Geol 1:512–521. https://doi.org/10.31035/cg2018073

    Article  Google Scholar 

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This study was partially funded by JSPS KAKENHI Grant No. JP25303016. We would like to thank Research England for granting funds for Dr Ravindra Jayaratne (UEL) to take part in and carry out field work in 2019, data analysis, technical discussions and manuscript preparation under the Global Challenges Research Fund (GCRF). We would like to thank Editage (www.editage.com) for English language editing.

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The design of the present study was originally developed by Sameera Maduranga Ratnayakage (SR) under the supervision of Jun Sasaki (JS) and revised with contributions of all the other authors. Material preparation, data collection, and analysis were performed by SR with the help of the co-authors. The first draft of the manuscript was prepared by SR with the revision by JS. All the authors made comments, which were accommodated by SR. All the authors confirmed and approved the final manuscript.

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Correspondence to Sameera Maduranga Samarasekara Ratnayakage.

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Ratnayakage, S.M.S., Sasaki, J., Suzuki, T. et al. On the status and mechanisms of coastal erosion in Marawila Beach, Sri Lanka. Nat Hazards 103, 1261–1289 (2020). https://doi.org/10.1007/s11069-020-04034-4

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  • Developing country
  • Coastline change
  • Wave climate change
  • Sand mining
  • Beach nourishment