Švihov - Drinking Water Reservoir Želivka River water quality in reservoir and catchment Marek Liška Povodí Vltavy, state enterprise 8/9/12 3 river basins - Elbe, Danube, Oder Vltava river catchment 5 River Boards Subunit of Elbe river basin Švihov reservoir 8/9/12 Švihov reservoir (on the Želivka river) Biggest drinking water source in Czech Rep. Supply of drinking water for 1.2 million inhabitant s CR Area of reservoir = 14.3 km2 Total volume = 266.6 million m3 Length = 38 km (canyon character) Theoretical retention time = 430 days (important) Q (m3/s) long-term average inflow = 6.9 m3/s Q (m3/s) inflow to waterworks cca = 3 m3/s Catchment area ~ 1 200 km2 3 retention reservoirs and 5 retention ponds 60 –8/9/12 80% arable land Švihov water reservoir The point of water withdrawal 27. října 2014 4 Švihov reservoir on the Želivka river building period • Building time – 1966 - 1972 • 1965 – preparing time (energy, infrastructure) • Dam • The point of water withdrawal • Catchment preparing safety • Tunnel Švihov-Prague 60 km spillway • Water storage reservoir Jesenice • Supplier: Vodní stavby n.p. • Budget: 764 m CZK • 1972 – 1978 reservoir water filling 5 outflow windows 27. října 2014 5 Water route from reservoir to waterworks Pumping station point of Waterworks Hulice water withtdrawal 8/9/12 Želivská provozní co. - waterworks Hulice Water Production (project): 7.7 m3/s I.line 3.3, II a III line 2.2 Water Production (recent reality): cca 3-3.5m3/s Technology: precipitation: Al2(SO4)3 sand filters hygienic protection: chlorine, ozon 8/9/12 Drinking water route: from waterworks to Prague Prague 60 km Švihov reservoir 3 sources of a drinking water for Prague •Prague Podolí – Vltava river (substitution source) •Káraný – Jizera river ( ~10 % of production) 8/9/12 •Švihov – Želivka river (~90 % of production) Monitoring water quality in tributaries in the catchment Start monitoring: 1972 ~ 40 sampling profiles period of sampling - 24/year parameters : • pH, O2, cond, t, P, N, BOD5, COD, TOC etc..) • chlorophyll, phytoplankton • heavy metals • organic compound (PCB, OCP, PAU, N- pesticides) Monitoring of Reservoir sampling interval: 30 days 6 vertical profiles Scheme of reservoir monitoring: Secchi (water clarity) integral samples (4m) zonality samples (0, 5, 10, 20, 30, 40, 50 m) vertical zonality: pH, t, O2, cond, chla., P+N phytoplankton, zooplankton priority compounds Changes of oxygen concentration on the longitudinal profile - Švihov reservoir Decrease of oxygen conc. in summer in the upper part of reservoir, at the dam area – only metalimnetic minimum IX. VII. X. VIII. 8/9/12 Longitudinal gradient eutrophic characteristics Švihov reservoir 2011 clarity – Secchi chlorophyll a total phosphorus on the longitudinal profile: with decreasing conc.P, decr. conc. chlorophyll a, phytoplankton8/9/12 and increase value of clarity Secchi disc Main risk factors for water quality of Švihov reservoir • Eutrophication: Phosphorus loading – P=100% eutrophication nutrient • Pesticides – compounds for growing technical crop: maize and rape-seed • Erosion of agriculture soil, loading rivers and reservoirs by sediment • Hydrological balance: drought period decrease of water volume in reservoir increased conc. P increased conc. of phytoplankton problems with water treatment Phosphorus: long-term trend: upper part of reservoir and DAM location upper part of reservoir DAM location 8/9/12 Sedlický: 0.5-0.7 P input t/year CO TO JE? Blažejovický: 0.2-0.3 ~7-12 t/year Martinický: 1.9-2.1 Trnava: 2.3-2.8 Jankovský: 1.5-1.7 Bělá/PE: Žel. Krasíkovice: 1.4-1.6 5 – 9 tP Dep.on rainfall I. Point sources of pollution phosphorus, nitrogen, drugs, PCPs 41 WWTP Pelhřimov Hněvkovice Čechtice Obrataň Lukavec Kaliště Pacov Moraveč Senožaty Lidmaň Výskytná Snět Dolní Kralovice D. d. Lukavec Červ.Řečice Ústí Želiv Brzotice Košetice Hořice Kožlí Leskovice Nová Cerekev Křivsoudov Hořepník Chmelná CEREPA Pavlov Loket Krasoňov Hojanovice Hořice Božejov Těchobuz Sedlice Krasoňov Onšov Tomice Vystrkov Vintířov Bernartice Blažejovice Results of monitoring WWTP 2012 phosphorus t/year 41 WWTP cca 5.7 tP/year (2012) 2011 inflow P to Švihov cca 11.2 tP/year Other sources of pollution: cca 5.5 t P/year (estimation) Drugs: point source of pollution Diclofenac - antiflogistic,antirevmatic Ibuprofen – antiflogistic, antirevmatic Carbamazepine - psychopharmacy, antiepileptic Iopromide - X ray agents (roentgen diagnostic) Sulfamethoxazol - sulfonamid chemoterapeutikum Erythromycin - antibiotic Hydrochlorothiazid - antihypertenzive, diuretic Metroprolol tartrare - antihypertenzive Furosemid - diuretic Drugs in waste water – outflow WWTPs Hydrochlorthiazid Concentration in surface water decreasing high blood pressure II. Erosion maize, rape-seed 50-80% arable land • decreasing of quality agricultural soil • new sediments in rivers, ponds and reservoirs • expensive extraction of sediments from reservoirs and rivers 8/9/12 3 retention reservoirs Improves water quality via: decreasing VLIV VN NĚMČICE - P celk VLIV VN NĚMČICE - PO4-P inflow0.40 erosion material, decreasing0.25 of Leský Mlýn Leský Mlýn 0.35 phosphorus and phytoplanktonVN odtok before0.20 VN odtok 0.30 0.25 0.15 -1 -1 entrance to Švihov reservoir 0.20 mg l • Highmg l 0.15 sedimentation of particular material0.10 0.10 0.05 • Necessity0.05 for sediment extraction 0.00 0.00 I-11 I-12 I-11 I-12 III-11 V-11 III-12 V-12 III-11 V-11 III-12 V-12 IX-11 XI-11 IX-12 XI-12 IX-11 XI-11 IX-12 XI-12 VII-11 VII-12 VII-11 VII-12 VLIV VN TRNÁVKA P celk VLIV VN TRNÁVKA PO4-P 0.30 0.15 Pod JIP Nad JIP 0.25 VN Odtok VN Odtok 0.20 0.10 -1 -1 0.15 mg l mg l 0.10 0.05 0.05 0.00 0.00 I-11 I-12 I-11 I-12 III-11 V-11 III-12 V-12 IX-11 XI-11 IX-12 XI-12 III-11 V-11 III-12 V-12 IX-11 XI-11 IX-12 XI-12 VII-11 VII-12 VII-11 VII-12 VLIV VN SEDLICE - P celk VLIV VN SEDLICE - PO4-P P retention0.50 : AVG retention ratio = 50%0.25 Trnávka,30% SedliceKojčice, Němčice Kojčice Vřesník 0.40 Vřesník 0.20 0.15 0.30 -1 -1 mg l mg l 0.20 0.10 0.05 0.10 0.00 0.00 I.11 I.12 III.11 V.11 III.12 V.12 I.11 I.12 IX.11 XI.11 IX.12 XI.12 VII.11 VII.12 III.11 V.11 III.12 V.12 IX.11 XI.11 IX.12 XI.12 VII.11 VII.12 III. Non-point sources of pollution Pesticides compounds , Nitrogen, Phosphorus, USE: A) Crop protection B) Total herbicides= total eradication of weeds Maize and Rape-seed: terbuthylazin (substitution prohibited atrazin), acetochlor, alachlor, metolachlor, metazachlor, linuron, diuron, chlortoluron + metabolites chloracetanilids(ESA,OA) Problem: In catchments with agricultural land use: Pesticide compounds in drinking water supply catchments in the Vltava river catchment 1. Nitrogene pesticides: 2. Pesticides of uronic acid: – terbutylazin and metabolites – diuron – acetochlor and metabolites – isoproturon – metolachlor and metabolites – chlorotoluron atrazin desethyl – linuron – Metabolites of metazachlor – – Metabolites of dimethachlor nicosulfuron – alachlor ESA 3. Total herbicides: – metamitron – glyphosate – metribuzin – AMPA – propiconazol 4. Insecticides: – tebuconazol – DEET – hexazinon Nitrogen pesticides – results of monitoring Terbuthylazin ng/l Sources: agricultural areas year average 2006-2012 Maize and rape-seed OK risk microcatchments in the catchment of rivers: Sázava, Želivka, Radbuza, Úhlava Important: small tributaries in agricultural catchment drainage large area with technical crop Changes of pesticides conc. in surface waters Concentration changes of terbuthylazin in rivers in agricultural catchment 1) Application – way and range Wet Dry period 2) Raining - intensity period (drought years – low conc., longer time, wet years- high conc., shorter time) Metabolites Acetochlor „parent compound“ Forms ESA a OA = metabolites (ethan sulfonic acid, oxalamic acid) „Parents compounds“ in water only in the time of application Metabolites ESA a OA- whole year in high concentration Nitrogen pesticides and its metabolites - threat to surface water, especially rivers and reservoirs with drinking water use!!! Sources of pesticides: Time of application: Small streams - drainage spring (V, VI), autumn (IX,X) large agricultural areas Sources of pesticides are usually a long distance from the river or reservoir Prohibited areas along the reservoirs and rivers are small Švihov - reservoir 2 sources of SW Úhlava - river WTP Hulice PAWR I a II step (protected area water resources) ~ 3.5m3/s ~ 1.2 m inhabitants WTP Plzeň Doudlevce ~0.45 m3/s 70% ~0.2 m inhabitants arable land Main sources of pesticides out of PAWR!!! 1178 km2 915 km2 Švihov reservoir Changes in concentration of pesticides in Point of water withdrawal – reservoir and in river deep 35m dam of reservoir TRT 1.25 year stabile concentration Úhlava Poin of water withdrawal from river high fluctuation in concentration winter and autumn conc. under detection limit <10 ng/l Terbuthylazin universal marker for use of pesticides for maize and rape-seed The highest concentrations in sub-catchment Sedlický stream Martinický stream Trnava river HOW to decrease pesticide content in drinking water Combine: I. measures in the protected area of water resources PAWR + II. Add water treatment technology I. Mitigation or restriction measures in the catchment of drinking water reservoir reduction of use of pesticides for technical crop growing, preferences for other type of land use – greening etc. II. Add water treatment technology – separate steps the most effective process - adsorption on GAC (active granulated carbon) membrane technology (use only some type of pesticides) oxidation by ozone oxygen – disadvantage of technology: residues of organic compounds stay in treatment water Conclusions Drinking water reservoir Švihov on Želivka river: • Supply of drinking water for 1.2 m inhabitants • Long - theoretical retention time = 430 days • 60 – 80% arable land in the catchment Main risk factors for the water quality of Švihov reservoir: • Eutrophication: Phosphorus from point sources • Erosion of agriculture soil, loading rivers and reservoirs by sediment • Pesticides – compounds for growing technical crop: maize and rape-seed • Hydrological balance: decrease of water volume in reservoir increasing conc.