Present state and advances in warning systems for floods in

http://arda.hydro.bg

http://maritsa.meteo.bg • WSF for and – description and actual state • WSF for – last development of ARDAFORECAST project • Expected outputs for northern Bulgaria - WATER project

•Eram Artinyan, Snezhana Balabanova, Georgy Koshinchanov, Nikolai Nedkov, Petko Tsarev WSF for Maritsa & Tundzha rivers

• Maritsa is the larger internal river basin for Bulgaria – in total 34200 km2 including 5200 km2 of Arda and 7900 km2 of Tundzha tributaries. The basin is shared among Bulgaria, and . • A mirror project was developed for Turkey with NIMH participation. It covers the region down to . • WSF for Bulgarian part is operational since 2009 • It covers the main river course of Maritsa and Tundzha rivers with flood forecasts for 5 days ahead for 22 riverside settlements \17+5\. • The system is based on Mike11 – hydrological and hydraulic models and the Floodwatch add-on module of DHI • runs twice daily - results are published on-line WSF for Maritsa and Tundzha

•Three warning levels roughly related to the bank full conditions. The “Alert!” levels is at A.S.L of the top of the dikes.

•High flood on Maritsa river at 06.02.2012 WSF for Maritsa and Tundzha – maintenance & development

•Maintenance: •User support: MOEW, Local administration and Civil Protection units •Warning levels adjustment •Bulk and hydraulic models parameter adjustment •Input data clean-up •Software maintenance and updates •Development: • Adding a new input point (real-time station) to implement initial conditions for Tundzha river •Building a WEB based SMS and e-mail sending application for automatic alert messages dissemination WSF for Arda river basin – ARDAFORECAST project Preliminary flood risk assessment

According to EU directive on the assessment and management of flood risks (2007/60/EC) • The map of important past floods • Information on expected climate changes (5-15 % increase of floods probability) • The present state of human infrastructure • A hydraulic modeling or regionalization procedure to determine the maximum discharge with 1% probability are used Regionalization procedure consists of determining two coefficients (for each set of sub-basins) that permit expressing maximum discharge with certain probability as function of the watershed area where hydrological measurements are not available WSF for Arda Preliminary flood risk assessment

• The map of important past floods • Information on expected climate changes (5-15 % increase of floods probability) • The present state of human infrastructure • A hydraulic modeling or regionalization procedure to determine the maximum discharge with 1% probability are used Regionalization procedure consists of determining two coefficients (for each set of sub-basins) that permit expressing maximum discharge with certain probability as function of the watershed area where hydrological measurements are not available WSF for Arda Hot-points and alert levels

• Hot-spots: areas for which flood warnings will be issued - combination of areas under high flood risk and of human infrastructure like settlements, roads, industrial buildings, agricultural fields, etc. • Alert levels: three water discharge thresholds – 1%, 5% and 50% probability of the yearly maximum discharges (latest occurs once every 2 years) Hot-points:

Smolyan Dzhebel Madan Moryanci BG/GR Source: http://www.bd-ibr.org/ border The core of the structure: HM modeling system for hydrological analysis and forecast •Based on ISBA-TOPMODEL coupled models •Surface scheme uses interpolated input data from telemetric stations and forecasted fields of precipitation, air temperature and moisture, wind speed and global solar and atmospheric radiation from ALADIN & ECMWF forecasts (5 days ahead) atmospheric models •Initialization of forecast run is done after running the system with measured precipitation and temperature input fields

• It computes evapotranspiration, surface runoff Qr [mm] and drainage D [mm] • Qr and D are transferred to TOPMODEL for routing • Discharges [m3/s] are computed at predefined cross-sections at 3h step WSF for Arda Working system for flood warnings & increasing technical capabilities.

• Installed equipment : 14 telemetric stations measuring water level in rivers and reservoirs, precipitation intensity, air temperature in Bulgaria and Greece

•ALERT TREHSHOLDS •HYDRO- METEOROLOGICAL •FLOOD MAPS PUBLISHED INFORMATION: •INFORMATION SYSTEM •AREAS UNDER RISK •RISK LEVEL •TIME LINE OF THE EVENT – EXPECTED •Web based DECISION BEGINNING-END SUPPORT INFORMATION SYSTEM

Overview of the structure of Warning system for floods - flowchart WSF for Arda Visualization: information on-line

On-line data published on web site - http://arda.hydro.bg & mapping and data servers.

• River level and discharge – real-time • 10 types of analytical and forecasting fields over the basin • Snow pack real-time data • Forecasts for 5 days ahead for 17 locations near the rivers • 3h step of the forecasted discharges

•10 successive forecasts are shown •Every box color represents the warning level of the computed discharge •Red:1% probability of max discharge, orange: 5%, yellow: 50% WSF for Arda Next steps and expected development

•A common SMS and e-mail server for alerts dissemination •Possible users: system administrators, local authorities, civil protection authorities •Increasing of the lead time of the forecast to 10 days.

WSF for North Bulgaria river – Artificial Neural Networks Yantra - Hydrological modeling with HEC HMS

•Perspectives:

Further development using already established tools, enhancing the links with the institutional and end users