Sustainable small wastewater systems in Central and Eastern Europe: Case study Slovenia

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1 13th IWA Specialized Conference on Small Water and Wastewater Systems & 5th IWA Specialized Conference on Resources Oriented Sanitation Sustainable small wastewater systems in Central and Eastern Europe: Case study Slovenia Istenič Darja*, Ameršek Iztok**, Hercog Andrej** and Müller Richard***, Tjaša Griessler Bulc* *Faculty for Health Sciences, University of Ljubljana, Slovenia ** Liviplant Ltd., Slovenia *** Global Water Partnership Central and Eastern Europe Ahtens,

2 GWP The Global Water Partnership (GWP) is a dynamic, not for profit action network with over 3,000 Partner organisations in 178 countries around the world. The network has 85 Country Water Partnerships and 13 Regional Water Partnerships.

3 GWP CEE Founded in 1998 Population of 152 million people, a quarter of all Europeans Total area of over 2.03 million km 2 12 countries in Baltic and Danube regions, 170 Partner organizations Baltic region: Estonia, Latvia, Lithuania and Poland Danube region: Bulgaria, Hungary, the Czech Republic, Moldova, Romania, Slovakia, Slovenia and Ukraine

4 Current status in CEE 30% of population lives in settlements with less than 2000 inhabitants This is >42 million people! Only 9% connected to WWTP! Discharge of untreated wastewater from the rest of small settlements represents a significant pollution of surface and groundwater and consequently a threat to human health.

5 Survey of small WWTP and TW Nr of small* WWTP Nr of TW % TW Guidelines/ standards for TW Bulgaria No Czech Republic Yes Estonia Yes Hungary Yes Latvia No Romania No Slovakia Yes Slovenia No Ukraine n.a. 65 / No Average/total % Istenic, Bodík, Bulc, 2015 *capacity <2000 PE, Data were obtained by questionnaire for sanitation experts from all CEE countries 1 person per country (from NGOs, Universities, private companies)

6 Legislation limits for small WWTP BG CZ EST H LA RO SK SLO UA <2000 PE BOD 5 / 25/ % 20 30/ mg/l COD / 120/ % / SS / 40/ < /60 / 15 NH 4 N / 15/30 / 4 / 15 / / 0.39 TP / 3/ / 2 / / / <500 PE BOD 5 / 40/ Appropriate treatment / 30/ COD / 150/ / 135/ SS / 50/ / 30/60 / 15 NH 4 N / 20/40 / 4 / / / 0.39 TP / / / / / / <50 PE BOD 5 / 95% / / / / 40/ COD / 90% / / / / / SS / / / / / / / / 15 NH 4 N / 50%N / / / / / / 0.39 TP / 40% / / / / / / /

7 Main barriers Unawareness območju National and local authorities, local communities Deficits in legislation Discharge limits, Lack of programmes/plans Negative experiences Malfunctioning TW due to lack of maintenance Additional barriers Land limitations Competition with agricultural land Hilly area Natural characteristics Severe winters/cold summers High groundwater levels Institutional barriers Market barriers

8 Case study: Slovenia Area km2 Population: Hills and mountains Karst areas Protected areas Dispersed settlements 60% of population lives in settlements with less than 5000 inhabitants

9 Wastewater treatment in small settlements Wastewater collection and treatment for settlements: PE by (COD 150 and BOD 30 mg/l) območju < 50 PE by 2021 (COD 200 mg/l) or ealier in the case of house reconstruction. This is 52% of the population!

10 TW Inventory in Slovenia Since TW (80 for sewage) have been built, območju PE % for family houses (up to 6 PE) No electrical equipment and pumping; using topography for gravitational water flow Also smallest TWs have two beds with different granulometry of sand

11 Vertical flow TW design Septic tank: Pulse shaft Plants Impermeable Layer EPDM liner or PP modul Designed for SLO legislation (150/200 mg/l for COD; 30 mg/l BOD5) area m 2 /PE pulse loading (8 12 pulses/day) COD outlet <80 mg/l BOD outlet <15 mg/l Outlet: stream, sink

12 Vertical flow TW size SLOVENIA (HF*) SLOVENIA (VF) DANISH GUIDELINES Area needed (m 2 /PE) > Legislation requirements COD < 200 mg/l O 2 COD < 125 mg/l O 2 BOD 5 < 25 mg/l O 2 and > 90 or 95 % NH 4 N + < 10 mg/l and > 90 % P total < 2 mg/l and > 90 %

13 VFTW for 3 PE 4.5.m2

14 Vertical flow TW performance 15 VFTW

15 Evapotranspirative willow systems (EWS) First pilot plant in Slovenia Watewater reuse for biomass production Zero outflow to estimate actual evapotranspiration and biomass production to test 3 willow clones

16 Conclusion Removal performance evaluation is being done in almost all the systems Robust low cost on site solutions e.g. TW The data gathered by the monitoring will be used for the formulation of the national guidelines Closing nutrient and water cycle (water reuse) Demonstration of good examples Awareness rising at institutional and administrative level Improvement of legislation

17 Thank you for your attention!