Preface Water-Quality EngineeringK Hanaki,UniversityofTokyo,Tokyo,Japan& 2011Elsevier B.V. Allrights reserved.Watertechnologyhasbeenevergrowing.Itisanessentialsetof technologies for sustainable human society. Traditionaltechnology, or better calledjust skill, toobtain, purify, andsupplywaterwasdevelopedintheancienterainvariousre-gions of the world. Great efforts have been made to obtain safeandadequatewater as anessential resourcetohumanlife.However,still,billionsofpeopleintheworldhavenoaccesstosafe water. Moreover, large numbers of people have nochancetouseapropersanitationsystem,andthiseventuallydeteriorates water quality and decreases the available safewaterresources.Water resources are renewable theoretically. Used waterdoes not disappear but is renewed to freshwater throughevaporationbythepower of solar energy. Solar energyis anatural distillationsystemtoremove impurities present inwater. However, the helpof water technologyis neededtomaintain this renewing function in the modern world inwhich human activity overwhelms the natural purifyingfunction.Conventional water technologywas usedas ablackboxthrough which water was puried without knowing themechanisms, whichcontrol thephysical, chemical, andbio-logical reactions used in purication. However, such empiricaluse of technology cannot further improve or develop thetechnology. Many researchers and practitioners have de-velopedtheory-basedtechnology, ratherthanmereempiricalskill, for purifying water. The function of each unit process wasstudiedandthe mechanisms of separation, role of micro-organisms, andprocess characteristics were claried. Asig-nicant amount of knowledge has beenaccumulated. Thisknowledge improves process performance and reliability.Human beingsalso developed tools to examinethe micro- ornanoscalereaction.Moderntechnologyneedstobebasedonadeepandbroadunderstandingoftheory.Watertechnologyisnotisolatedfromothertechnologies.Manyinnovationstoupgradewater-technologyperformancehave beentried by applying newtechnologies fromotherelds. Membrane technology that originated in a eld such asmedical science or chemical engineering is an example.Nowadays, water treatment is oneof thelargest applicationareasofmembranetechnology.The purposeof water technologyhas beenexpandedfrompuricationof water to water generation, energy and resourcerecovery.Thisisapracticalandimportantareatowhichnewtechnology can be applied. Water availability is limitinghuman settlements. The supply of water produced fromseawaterorevenmoisturecanbreakthroughthislimitation.Therequirements for water technologydiffer verymuchfromoneplacetotheother. Thekeyfactorsaretarget com-pounds tobe removed, resource andenergyconsideration,capacityof operatinghumanresources, aswell aseconomicresources. For example, asafewater-supplysysteminleast-developed areas needs technology, which can be used withoutfrequent and sophisticated maintenance. However, suchtechnologydoesnotmeancheapandoldtechnology.Newlydevelopedinnovativetechnologyhasahigherchanceofim-plementationthanoldtechnology.Water management needs policyandsystemtechnologyrather thansimple connectionof unit technologies. Adis-tributedwastewatertreatmentsystemneedsreliableandeco-nomically and technologically reasonable treatmenttechnologies. A nutrient removal policy for eutrophication canberealizedbyintroducingatechnologicallyreasonablecom-binationof secondary andadvancedtreatments. The watertechnologyisasystemtechnology.Resource and energy limitation has become a key factor forsustainability. Substantial amount of material use threatensthe worlds resources, andenergy use provokes the climatechangeproblem. Savingresourceandenergyis nowanin-dispensableaspect of watertechnology. Thenecessityof en-ergyandresource saving further changes water technology.The current global situationregarding climate change andresource limitation enhances the recovery of resource andenergy. Wastewater contains organic matter, which is biomass;therefore,obtainingcarbon-neutralenergyispossible.Water technology is nowforming animportant part ofbusinessworldwide. Everycountryneedssafewater anden-vironmental protectionfromwastewater. Technology devel-opment, implementation, and maintenance providesubstantialopportunitiesforbusiness.This volume includes theory, practice, andrecent devel-opment of thesewiderangeof watertechnologies, althoughallsuchinnovativetechnologiescannotbeincluded.Thereisnosingleanswertoanyoftheparticularcases.Amongmanyoptions,oneshouldchooseatechnologysystemconsideringthelocalsocial,economic,andengineeringaspects.Thisvol-umewouldhelpsuchatechnologychoice.14.01 Water and Wastewater Management Technologies in the Ancient Greekand Roman CivilizationsG De Feo,UniversityofSalerno,Fisciano(SA),ItalyLW Mays,ArizonaStateUniversity,Tempe,AZ,USAAN Angelakis,InstituteofIraklion,Iraklion,Crete,Greece& 2011Elsevier B.V. Allrights reserved.4.01.1 Aqueducts 44.01.2 Minoan and Greek Aqueducts 44.01.3 Roman Aqueducts 54.01.4 Cisterns and Reservoirs 84.01.5 Water Distribution Systems 114.01.6 Fountains 144.01.7 Drainage and Sewerage Systems and Toilets 154.01.8 Discussion and Conclusions 19References 21ProlegomenaThepastisthekeyforthefutureHydor(Water)isthebeginningofeverythingThalesfromMiletus(c.636546 BC).Humans havespent most of their existenceas huntingandfood-gatheringbeings.Onlyinthelastc.900010 000years,they discovered howto growagricultural crops and tameanimals. Such revolution probably rst took place in the hillsto the northof Mesopotamia. Fromthere the agriculturalrevolutionspreadtotheNileandIndusValleys. Duringthisagricultural revolution, permanent villages replaceda wan-dering existence. About 60007000 years ago, farming villagesoftheNearEastandMiddleEastbecamecities.Hydraulictechnologybeganduringantiquitylongbeforethe great works of suchinvestigators suchas LeonardodaVinci (14521519) and Isaac Newton (16421727), and evenlongbeforeArchimedes(287212 BC)(Mays, 2008). Duringthe Neolithic age (c. 57003200BC), the rst successful effortstocontrol thewaterowweredriven(suchasdamsandir-rigation systems) due to the food needs and were imple-mented in Mesopotamia and Egypt (Mays et al., 2007). Urbanwater-supply andsanitationsystemsaredatedatalaterstage,intheBronzeAge(c.32001100 BC).Regarding the technological principles related to water andwastewater, todayit is well documentedthat manyarenotachievements of present day, but date back to 30004000 yearsago. Theseachievements includebothwater andwastewaterconstructions(suchasdams, wells, cisterns, aqueducts, sewer-age and drainage systems, toilets, and even recreationalstructures). Thesehydraulic works alsoreect advancedsci-enticknowledge,whichallowedtheconstructionoftunnelsfromtwoopeningsandthetransportationof waterbothbygravity owinopenchannels and by pressurized owinclosedconduits. Certainly, technological developments weredriven by the necessities to make efcient use of naturalresources, to make civilizations more resistant to destruc-tivenatural elements, andtoimprovethestandards of life.Withrespecttothelatter, theGreek(includingMinoan)andRoman civilizations developed an advanced, comfortable, andhygienic lifestyle, as manifested frompublic and privatebathroomsandushingtoilets,whichcanonlybecomparedto the modern one, re-established in Europe and NorthAmericainthebeginningofthelastcentury.Minoantechnological developments inwater andwaste-water management principles andpractices are not as wellknown as other achievements of the Minoan civilization, suchas poetry, philosophy, sciences, politics, and visual arts.However, archaeological and other evidence indicate that,duringtheBronzeAgeinCrete,advancedwatermanagementandsanitarytechniqueswerepracticedinseveralpalacesandsettlements. This periodwas calledbythe excavator of thepalace at Knossos, Sir Arthur Evans, as Minoan after thelegendary King Minos. Thus, Crete became the cradle of one ofthe most important civilizations of mankind andthe rstmajorcivilizationinEurope.One of the major achievements of the Minoans was theadvancedwaterandwastewatermanagement techniquesprac-ticed in Crete during that time. The advanced water distributionandsewerage systems invarious Minoanpalaces andsettle-ments are remarkable. These techniques include the con-structionanduseof aqueducts, cisterns, wells, andfountains,the water-supply systems, the constructionanduse of bath-rooms andother sanitaryandpurgatoryfacilities, as well aswastewater and stormwater sewerage systems. The hydraulic andarchitecturalfunctionofthe water-supply and sewer systemsinpalacesandcitiesareregardedasoneofthesalientcharacter-istics of the Minoan civilization. These systems were so advancedthat theycanbecomparedwiththemodernsystems, whichwere establishedonly inthe second half of the nineteenthcentury in European and American cities (Angelakis et al., 2010).Water andwastewatertechnologiesdevelopedduringtheMinoan, Greek, and Roman civilizations are considered in thischapter. Emphasis is given to the water resources developmentsuchasaqueducts, cisterns, wells, distributionsystems, was-tewaterandstormwaterseweragesystemsconstruction, oper-ation, and management beginning since Minoan times(secondmillenniumBC). Theachievements tosupport the3hygienic and the functional requirements of palaces and citiesduringthis timeweresoadvancedthat couldbeparalleledonlytomodernurbanwatersystemsthatweredevelopedinEurope andNorthAmerica onlyinthe secondhalf of thenineteenthcentury(AngelakisandSpyridakis,1996).Itshouldbenotedthathydraulictechnologiesdevelopedduring the Greek and Roman periods are not limited to urbanwater andwastewater systems. Theprogress inurbanwatersupply was even more admirable, as witnessed by severalaqueducts, cisterns, wells, and other water facilities discovered(Koutsoyiannis et al., 2008). These advancedMinoantech-nologieswereexpandedtotheGreekmainlandinlaterperi-odsoftheGreekcivilization, thatis, inMycenaean, Archaic,Classical, Hellenistic, andRomanperiods. Inthis chapter, arather synoptic descriptionof the mainconcepts of waterandwastewatermanagementduringtheMinoan, Greek, andRoman civilization is attempted. The main principles andchallengesarealsodiscussed.4.01.1 AqueductsAqueductswereusedtotransportwaterfromasourcetothelocationswherethewaterwasneeded,eitherforirrigationorfor urban water supplies, and have been used since the BronzeAge. Aqueduct bridgesareman-madeconduitsfortransport-ing water across rivers, streams, and valleys. As a matter of fact,a systematic evolution of water management in ancient GreecebeganinCreteduringtheearlyBronzeAge,thatis,theEarlyMinoanperiod(c. 35002150BC)(Myersetal., 1992; Mays,2007). Starting the Early Minoan period II (c. 29902300 BC),a variety of technologies such as wells, cisterns, and aqueductswereused(Mays,2007).4.01.2 Minoan and Greek AqueductsThe water distribution systemat Knossos, as well as themountainous terrain and available springs made possibletheexistenceofanaqueduct(Mays,2007;Maysetal.,2007).The Minoaninhabitants of Knossos dependedpartially onwells,andmostlyonwaterprovidedbytheKairatosRivertotheeast of thelowhill of thepalace, andonsprings. Indi-cations suggest that thewater-supplysystemof theKnossospalace initially relied on the spring of Mavrokolybos (called soby Evans),alimestonespringlocated450msouthwest ofthepalace(Angelakisetal.,2007; Evans,19211935; Maysetal.,2007).Inlaterperiodswiththeincreaseofpopulation,othersprings at further longer distances were utilized. Thus, anaqueductmadeofterracotta pipecouldhave crosseda bridgeonasmall streamsouthof the palacewhichcarriedwaterfroma perennial spring on the Gypsadhes hill (Graham,1987;Mays,2007).Asecondexampleof anaqueduct wasfoundinTylissos(seeFigure1(a)).Partsofthestoneaqueduct,withthemainconduit at the entrance of the complex of houses, andother secondarysystems ledthewater toacisterndatedatc. 14251390 BC (Mays et al., 2007). Other aqueducts were inGournia, Malia, and Mochlos. These technologies were furtherdeveloped during the Hellenistic and Roman periods in Crete,andweretransferredtocontinental Greeceas well as otherMediterranean locations (Angelakis et al., 2007; Angelakis andSpyridakis,2010).IntheArchaicandtheClassicalperiodsoftheGreekcivil-ization, aqueductswerebuilt similartotheonesbuilt bytheMinoansandMycenaeans. Oneofthemostrenownedwater-supply systemsis the tunnel of Eupalinos on Samos Island.Infact, it is the rst deep tunnel in history that was dug from twoopeningswiththetwolinesofconstructionmeetingataboutthe central point of the distance. The construction of this tunnelwasmadepossiblebytheprogressingeometryandgeodesythat was necessary toimplement twoindependent lines ofconstruction that would meet (Koutsoyiannis et al., 2008; Mayset al., 2007). The Samos aqueduct system includes the 1036-m-longtunnelandtwoadditionalpartsforatotallengthgreaterthan2800m. Its constructionstartedin530BC, duringthetyrannyofPolycratesandlasted10years. ItwasinoperationuntilthefthcenturyAD(Koutsoyiannisetal.,2008).Figure 1 Ancient Minoan and Greek aqueducts: (a) aqueduct entering Tylissos showing the stone cover and (b) Peisistratean aqueduct consisting ofterracotta pipe segments and elliptical pipeopenings ineach pipe.Copyright permission withLW Mays.4 Water and Wastewater Management Technologies in the Ancient Greek and Roman CivilizationsObviously, there are several other acknowledged aqueductsinGreekcitiessincewatersupplywasregardedacrucialandindispensable infrastructure of every city (Tassios, 2007).Aqueducts (either tunnels or trenches) were always sub-terraneanduetosafetyandsecurityreasons. Usually, at theentrance of the city, aqueducts would branch out in the city tofeedcisterns andpublic fountains incentral locations. Theaqueducts were pipes (usually terracotta) laying in the bottomoftrenchesortunnelsallowingforprotection. Oneormorepipes inparallel wereuseddependingupontheowtobeconveyed. The terracotta pipes (2025cm in diameter) t intoeachotherandallow accessforcleaningandmaintenancebyelliptic openings that were covered by terracotta covers (Mays,2007;Maysetal.,2007).Water conveyed by aqueducts typically originated fromkarsticsprings.Asthehistoryteachesus,thepresenceofnat-uralspringswasaprerequisitefortheselectionofanareatosettle. As a matter of fact, the Acropolis at Athens hadanaquifer andaspringnamedClepsydra. Withtheintensiedurbandevelopmentaswellastheincreaseofpopulation,thenatural springs were not able to cover the water demand. Thus,the increasing water scarcity was remedied by transferringwater fromdistant springs byaqueducts, diggingwells, andconstructingcisternsforrainwaterstorage.InAthensallthesealternatives coexisted: the Peisistratean aqueduct (seeFigure1(b))constructedbytheendofthesixthcenturyBCwas accompaniedwithnumerous wells andcisterns. Legis-lative andinstitutional tools were developedinAthens inordertowiselyandeffectivelymanageawater-supplysystemwith public and private elements (Mays et al., 2007;Koutsoyiannisetal.,2008).Subsequently, the technologies developed in ancientGreece were transferred to the Greek colonies both to the eastin Ionia (Asia Minor, nowadays Turkey) and to the west in theItalianpeninsula, Sicily, andotherMediterraneansites, mostofwhichwerefoundedduringthearchaicperiod.AbrilliantexampleofthiswasthefoundingofSyracuse(onSicily)asacolonyofCorinthin734 BC(Maysetal.,2007).Later, duringtheHellenisticperiod, furtherdevelopmentswere accomplishedby the Greeks inthe constructionandoperationofaqueductsduetotheprogressinsciencewhichledanewtechnical expertise. Hellenistic aqueducts usuallyusedpipesaswell astheycontinuedtobesubterraneanforsafetyreasons(war, earthquakes, etc.). Thescienticprogressinhydraulic(especiallyduetoArchimedes, Heroof Alexan-dria) allowedthe constructionof invertedsiphons at largescales toconveywater across valleys (lengths of kilometers,hydraulicheadsofhundredsofmeters)(Koutsoyiannisetal.,2007,2008;Mays,2007;Maysetal.,2007).4.01.3 RomanAqueductsSprings, byfar, werethemost commonsourcesof waterforaqueducts even with the Romans. Water sources for the GreeksandRomansystems includednot onlysprings, percolationwells, and weirs on streams, but also lakes that were developedbybuildingdams. Atancient AugustaEmerita, at present-dayMerida, Spain, theRomanwater systemincludedtworeser-voirs createdby the constructionof the CornalvoandtheProserpina dams. The Proserpina damis anearthendam,approximately 427m long and 12 m high. The Cornalvo damisanearthendam,approximately194 mlongand20mhighwith an 8 m dam crest width. Both of these dams are still usedinthe present day, obviously withmodications over theyears. Dams were built in many regions of the Roman Empire.Aqueducts consisted of many components, including openchannelsandpipes. ThemaintypesofconduitsusedbytheRomansare:(1)openchannels(rivipercanalesstructiles),(2)leadpipes(stuliplumbei), (3)earthenware(terracotta)pipes(tubilictiles),and(4)woodpipes.Openchannelswerebuiltusingmasonryorwerecutintherockandowsweredrivenby gravity, while the leadpipes were usedfor pressurizedconduits includinginvertedsiphons. Aschemerepresentingthe general pathofa wholeaqueductwith the basicelementsis presentedinFigure2. Obviously, therearemanysystemcongurations that were built by the Romans andGreeks;however, the drawing presents the major components, in-cluding the siphon (inverted siphon) which was used in somesystems. Various types of pipes constructedbythe Romansincludedterracotta,lead,wood,andstone.Oneof themost impressiveRomanaqueductsinRomanGreeceis that intheAegeanislandLesvos (Figure3). It isprobablyaworkof late secondor early thirdcentury AD.It was mainlyusedfor water supplyof Mytilenetown, thecapital of theisland, andfor water supplyandirrigationofthe southeastern area of the island, by transporting water fromthe lake of Megali Limni (big lake), at the Olympus mountain, 1 2 3 4 5 6 7 8 9 11 10Figure 2 Flow sheet and components of a Roman aqueduct: (1) source caput aquae; (2) steep chutes (dropshafts); (3) settling tank; (4) tunnel andshafts; (5) covered trench; (6) aqueduct bridge; (7) inverted siphon; (8) substruction; (9) arcade; (10) distribution basin/castellum aquae divisorium;(11) water distribution system. From DeFeo G and Napoli RMA (2007) Historical development of the Augustan aqueduct in Southern Italy: Twentycenturies of works from Serino toNaples. WaterScience and Technology:WaterSupply 7(1): 131138.Water and Wastewater Management Technologies in the Ancient Greek and Roman Civilizations 5wheretheconstructionbegins.Theaqueductwasalsofedbyother secondarysprings, suchasthespringsat theAgiassouarea(i.e., Karini). It was passedthroughaveryanomalouslandscape relief; thus, it includes parts onthe soil surface,tunnels,andbridges.ThetotallengthoftheLesvosaqueductis 26km, withauniformslopeof 0.0096mm1. Its depthranges from 0.65 to 1.10 m and its width from 0.35 to 0.64 m(Karakostantinou, 2006). Itsmaximumcapacityisestimatedtobeof25000m3d1aalongthedistanceof26 km,aroutethat wasentirelysupportedbygravity. Today, themaximumwater supply of the town (15000m3d1) is pumpingfromsprings of Ydata located ina lower level of that ofKarini (MytileneMunicipal Enterprisefor Water SupplyandSewerage, 2009, personal communication. Mytileni, Greece).Its remains at the village of Moria are 170 m long and 27 m inheight and consist of 17 arches, also called Kamares laying ontheircolumn(Figure3(a)).Eachopeningisdividedinthreesuccessive arches based oncolumns. The masonry is con-structedwiththeuseofemplektonsystem(Karakostantinou,2006). Thecolumnsandarcheswereconstructedfromlargeblocksof graymarbletakenfromtheisland; thesematerialswere verystrong andresistant todecay(Figure 3(b)). Thedistribution of the arches along the openings consists of threeat a time up and down for every opening. The openings aredelimitedby columns,andeachcolumnhasanabacus.Siphons(Figure2(g))werebuilt bytheRomansalso, infact manyof the siphons may very well have beenstartedbytheGreeks andcompletedbytheRomans. Thesiphonsincludeda header tankfor transitioning the openchannelow of the aqueduct into one or more pipes, the bends calledgeniculus, the venter bridge to support the pipes in the valley,andthetransitionofpipeowtoopenchannelowusingareceivingtank.Locations of siphons included Ephesus, Methymna,Magnesia, Philadelphia, bothAntiochias, Blaundros, Patara,Smyrna, Prymnessos, Tralleis, Trapezopolis, Apameia, Akmo-nia, Laodikeia, and Pergamon (Mays et al., 2007; Tassios,2007). Thesesiphonswere initiallybuiltwithterracottapipesor stone pipes (square stone blocks towhicha hole wascarved) such as the inverted siphon at Patara (Turkey), showninFigure 4 (Haberey, 1972). As showninthe gure thissiphonwasconstructedfromcarvedstonesegments. Never-theless,theneedforhigherpressuresnaturallyledtotheuseof metal pipes, specically fromlead. One of the largestsiphons was the Beaunant siphonof the aqueduct of the GierRiver whichsuppliedthe Romancityof Lugdunum(Lyon,France). This siphon had nine lead pipes with a total length of2.6 km. This siphon was 2600m long and 123m deep with anestimated(Hodge,2002)dischargeof25000m3d1.PergamonwasacityinwesternTurkeyatthepresent-daycityof Bergama. TheHelenistic aqueducts constructedwerethe Attalos, the Demophon, the Madradag, the Nikephorium,andtheAsklepieion. TheRomanaqueductsconstructedwerethe Madradag channel, the Kaikos, and the Aksu. TheMadradag aqueduct whichhada triple pipeline (terracottapipe)ofmorethan50kmlongincludedaninvertedsiphon(madeoflead)longerthan3.5 km withamaximumpressurehead of about 190m (Mays et al., 2007; Tassios, 2007). It tookanother 2000years later before another pipeline was con-structedthatcouldbearahigherpressure(Fahlbusch,2006).In particular, the Attalos aqueduct was the rst pipeline(buried of red clay, and 13 cm inner diameter) in Pergamon,anditwas probablyconstructedinthemiddleorsecondhalfofthethirdcenturyBC, bringingwaterfromaspringinthemountains north of Pergamon (Fahlbusch, 2006; Mays, 2007;Oziz,1987,1996).The Romans built mega water-supply systems includingmany magnicent structures. As a matter of fact, Romanaqueducts became very famous all over the world, with Romeswater-supplysystembeingconsideredoneof themarvelsoftheancient world(Hodge, 2002; DeFeoandNapoli, 2007;DeFeoet al., 2009b; Mays, 2007; Mayset al., 2007). Infact,the Romans were urban people and consumed enormousamount of drinkingwater inorder tosupplybaths, publicanddecorativefountains, residences, gardenirrigation, ourmills, aquatic shows, and swimming pools (Hodge, 2002;Tolle-Kastenbein, 2005; De FeoandNapoli, 2007; De Feoet al., 2009b; Mavromati and Chryssaidis, 2007). However, theFigure 3 Part of theimpressiveRoman aqueductrises 600 m westMoria, aLesvian village at6 km from Mytilene town: (a) general view oftheremains and (b) thebase of columns. Copyright permission withAN Angelakis.6 Water and Wastewater Management Technologies in the Ancient Greek and Roman CivilizationsRoman aqueducts were not built with the primary purpose ofprovidingdrinkingwater,nortopromotehygiene,butrathertosupply the thermae andbaths or for military purposes(Hodge, 2002; De Feo and Napoli, 2007; De Feo et al., 2009b).The descriptionof the ancient Romanwater-supply systemiscontainedinsomerecommendationsof theLatinwriters:Vitruvius Pollio (De Architectura, book VIII), Plinio theElder (Naturalis Historia, bookXXXVI), andFrontinus (DeAquaeductuUrbisRomae).Romanhydraulicengineeringborrowedfromtheexperi-encesandtechniquesoftheGreeksandEtruscans. However,thesizeof theworksaswell asthetechnical-organizationalfeatures of distribution started with them. The common Greekpractice was based on underground conduits, followingcoursesdeterminedby terrainfeatures(MartiniandDrusiani,2009). The Etruscancivilization ourished incentral Italyfrom the VIII century BC onward. The Etruscan talent for waterandlandmanagement ishighlightedbytheexistenceof animposing number of works (tunnels andchannels) spreadover their territories of Latium and, to a lesser amount, of theotherEtruscanareas(Bersanietal.,2010).Theconstructionof anancient Romanaqueduct wasnotdifferent fromthe modern practice, with several moderntechnologiescomingfromRomanengineering. Thebuildingof anaqueduct startedwiththe searchfor a spring. Waterwas collectedafter permeating throughvaults andwalls ofdrainingchannelsandsettled. Fromthespring, waterowedintoanopenchannelow and airwas presentoverthe watersurface(Monteleoneetal.,2007).Thewaterintheaqueductsdescended gently through concrete channels. During theroute, thereweremultitieredviaducts, invertedsiphons, andtunnels toexceedvalleys or steeppoints. At the endof itscourse, the channel enteredintoaso-calledpiscinalimaria,a sedimentationtanktosettle particulate impurities. Then,thechannel owedintoapartitioningtankcalledcastellumdivisoriumwherethereweresomewallsandweirstoregulatethewaterowingintotheurbanpressurepipes(DeFeoandNapoli,2007;Monteleoneetal.,2007).RomeoriginallyusedwaterdirectlyfromtheriverTiberaswellaswellsandmanysmall springs existed inside its town area, such as AcqueLautole, Acque Tulliane, Fonte Giuturna, and Fonte Lupercale.However, sincethefourthcenturyBC, Romegraduallybuiltaqueducts(BonoandBoni,1996).Aqua Appia was the rst aqueduct built in Rome in 312 BC.It was entirely underground for a total length of around16.561 km, equivalent to 11190 passus (1 passus 1.48 m) andanaverageow rate of73000m3d1,correspondingto1825quinariae (1 quinaria B40 m3d1) (Table 1; Panimolle, 1984).It isimportant tospecifythat aquinariahasnot beenscien-ticallydened. Asamatteroffact, aquinariawasapipeof2.3125 cmdiameterandthereisnounanimityonhowmuchwater is aquinaria(Rodgers, 2004). DuringthesubsequentFigure 4 Inverted siphons. (a)Inverted siphon atPatara (Turkey) made of stone pipes. (b)Reconstructionof siphon of the aqueduct ofGier,near Beaunant, France that supplied water to Ancient Lugdunum, showing ramp of siphon with header tank on the top and the nine lead pipes of thesiphon. (a) From MaysLW (ed.)(2010) Ancient WaterTechnologies.Dordrecht: Springer and (b) From Haberey W(1972) Die romischenWasserleitungen nach Koln.Bonn: Rheinland-Verlag.Water and Wastewater Management Technologies in the Ancient Greek and Roman Civilizations 7500 years, 10 more aqueducts were constructed. The last greataqueductbuiltinRomeinancienttimeswasthe22-km-longAquaAlexandrina.Onthewhole,the11ImperialAgeRomanaqueductshadatotal owrate of 1.13 106m3d1andatotal lengthofmorethan500km.SincethepopulationofRomeattheendoftherstcenturyADwasabout500000inhabitants(Bonoand Boni, 1996), a mean specic discharge of B2000linhabitant1d1wasproduced.Thisvalueisextraordinaryifcomparedwiththecurrent specicwateruseof B200300linhabitant1d1.Nowadays, the popular but inaccurate image is that Romanaqueducts were elevatedthroughout their entire lengthonlines of arches, called arcades. Roman engineers, as their Greekpredecessors, were very practical and therefore wheneverpossible the aqueduct followed a steady downhill course at orbelowground level (Hansen, 2006). As a matter of fact,Table 1 shows that on average 87% of the length of the Romesaqueductsystemwasunderground.The longest aqueduct in the Roman world was constructedintheCampaniaRegion,inSouthernItaly.ItistheAugustanAqueduct Serino-Naples-Miseno, which is not well known duetotherebeingnoremainsofspectacularbridges,butitwasamasterpiece of engineering. The Serinoaqueduct was con-structedduringthe Augustus periodof the RomanEmpire,probably between 33 and 12 BC when Marcus VipsaniusAgrippawascurator aquaruminRome, principallyinordertorefurnishtheRomaneetofMisenumandsecondarilytosupply water for the increasing demand of the importantcommercial harbor of Puteoli as well as drinking water for bigcitiessuchasCumaeandNeapolis.ThemainchanneloftheSerino aqueduct was approximately 96 kmlong, and hadseven mainbranches to towns such as Nola, Pompeii, Acerra,Herculaneum, Atella, Pausillipon, Nisida, Puteoli, Cumae, andBaiae(DeFeoandNapoli,2007;DeFeoetal.,2010).InsummarytheRomansmadegreatcontributionstotheadvancement of the engineering of aqueducts. Fahlbusch(2006)pointsout thefollowingfromexaminationof manyaqueducts:1. sizeoftheaqueductchannelwaschosenaccordingtotheestimated discharge and the size varied along the course oftheaqueduct;2. the cross sectionwas large enoughfor people towalkthroughthechannel forrepairandmaintenance, particu-larlytoremovecalcareousdeposits;and3. the cross section was kept constant allowing manifold usesfor encasings, especially the soft scaffoldings for the vaultsinakindofindustrializedconstruction.4.01.4 Cisterns and ReservoirsIngeneral,cisternswereusuallyconstructedinordertostorerainwater for domestic use (private houses), with a volume inthe order of dozens of cubic meters, while reservoirs wererealizedinordertostoreowingwaterwithavolumeintheorder of thousandsof cubicmeters(Tolle-Kastenbein, 2005;DeFeoetal.,2010).The MinoanandMycenaeansettlements usedcisterns a1000years before the classical andHellenistic-Greek cities.Cisterns were used to supply (store runoff from roof tops andcourt yards)waterforthehouseholdsthroughthedrysum-mers of the Mediterranean. In ancient Crete, in particular, thetechnology of surface andrainwater storage incisterns forwatersupplywashighlydevelopedandhascontinuedtobeusedinmoderntimes.One of the earliest Minoan cisterns was found in the centerof a pre-palatial house complex at Chamaizi dating back to theturn of the second millennium BC. It is located on the summitof ahill andits rooms weresituatedaroundasmall opencourtwithadeepcircularrock-cutcistern,3.5 mindeepandwithadiameter of 1.5 m, linedwithbrickworkinitsupperpart (Davaras, 1976; Mays et al., 2007; Angelakis andTable 1 Characteristicsof the11 Imperial Age Roman aqueductsLocation Dating Length(km)Underground length(km (%))Averageslope(mkm1)Flowrate(m3d1)Aqua Appia 312 BC 16.561 16.472 (99.5%) 0.6 73 000Anio Vetus 273 BC 63.640 63.312 (99.5%) 3.6 175 920Aqua Marcia 144 BC 91.331 80.286 (87.9%) 2.7 187 600Aqua Tepula 127 BC 17.800 5 17 800Aqua Julia 33 BC 22.830 12.470 (54.6%) 12.4 48 240Aqua Virgo 19 BC 20.875 19.040 (91.2%) 0.2 100 160Aqua Alsietina 2 BC 32.882 32.814 (99.8%) 6 15 680Aqua Claudia 52 AD 68.977 53.620 (77.7%) 3.8 184 280Anio Novus 52 AD 86.876 72.964 (84.0%) 3.8 189 520Aqua Traiana 109 AD 58.000 3.8 113 100Aqua Alexandrina 226 AD 22.000 1 21 025Average 45.616 43.872 (86.8%) 3.9 102 393Total 501.772 350.978 1 126 325From Panimolle G (1984) Gli Acquedotti di Roma Antica (The Aqueducts of Ancient Rome). Rome: Edizioni Abete; Adam JP (1988) LArte di Costruire presso i Romani. Materiali eTecniche(RomanBuilding: MaterialsandTechniques).Milan: Longanesi; BonoPandBoni C(1996)Watersupplyof Romeinantiquityandtoday. Environmental Geology27:126134; Hodge AT (2002) Roman Aqueducts &Water Supply, 2nd edn. London: Gerald Duckworth; Rodgers RH (2004) Sextus Iulius Frontinus. On the Water-Management of theCityof Rome. DeAquaeductuUrbisRomae.Cambridge: CambridgeUniversityPress.8 Water and Wastewater Management Technologies in the Ancient Greek and Roman CivilizationsSpyridakis, 2010). Four of the earliest Minoan structures whichmaybeconsideredtobelargecisternswerebuiltinthersthalf of thesecondmillenniumBCat Pyrgos-Myrtos(Ierape-tra), Archanes, Tylissos, andZakros (Cadogan, 2007; Mayset al., 2007; AngelakisandSpyridakis, 2010). While, at Phai-stos, water supplied to cisterns depended onprecipitationcollectedfromrooftopsandcourts, asupplementarysystemwasneededtosatisfytheneedsofwatersupply,especiallyinthis particular area where agriculture was widely practiced.Thus, water was probably taken fromwells in a locationsouthwest of thepalacewhichwasrichingroundwaterandsurfacewater, andfromtheriverIeropotamoslocatedtothenorth, at thefoot of thePhaistos hill (Gorokhovich, 2005;Maysetal.,2007;AngelakisandSpyridakis,2010).Therewerealsocisterns onthehighgrounds abovetheMinoanpalace inMalia, ina site lying ina narrowplainbetweenthemountainsandthesea. AtthefamousPhaistospalace, cisterns depended on precipitation collected fromrooftopsandyards. Asupplementarysystemofwatersupplywasneededtosatisfytheneedsofwatersupply,especiallyinthoseareaswhereagriculturewasintensive.Thecisternswereconnectedtosmall channels collectingspringwater and/orrainfallrunofffromcatchmentareas.Theuseofcisternspre-cededchannelsoraqueductsinsupplyingthepalaceandthesurroundingcommunitywithwater(Maysetal.,2007;Ange-lakisandSpyridakis,2010).Most Greek houseshad a cisternsupplied by rainwater forpurposes of bathing, cleaning, houseplants, domestic animals,andevenfordrinkingduringshortagesofwater. Mostlikely,thewater was of aqualitythat wouldbesubpotableusingtodaysstandards.AristotleinhisPolitics(vii,1330b)writtenaround320BCassertedthat cities needcisterns for safetyin war. During this time a severe 25-year drought required thecollection and saving of rainwater. Also about this timecisternswerebuiltintheAthenianAgoraforthersttimeincenturies (Crouch, 1993; Mays, 2007). Inparticular, intheancientGreekcityofDrerosonCrete, thereisarectangular-shaped cistern with dimensions of approximately 13.0 5.5 6.0 m3(Antoniouetal.,2006;Mays,2007).Inancient Crete, thetechnologyof surfaceandrainwaterstorage in cisterns is continued to be used even today. Four ofthe earliestMinoan structures which may be considered to belargecisterns werebuilt intherst half of thesecondmil-lenniumBC(thetimeoftherstMinoanpalaces)atPyrgos-Myrtos(Ierapetra), Archanes, Tylissos,andZakros(Angelakiset al., 2010). The Tylissos cistern is shown in Figure 5(a). ThistechnologyhasbeenfurtherimprovedduringtheHellenisticandRomanperiods. Animpressive pillar of twointercon-nected cisterns, 40m deep cut in the rock, has been discoveredinancient cityEleutherna(Figure5(b)). Thedimensionsofthetwocisternsare40 25 m2andthedepth4.5 m.Thecityourished inthe early Christiantimes andthe water wastransported from a spring through an aqueduct of about 3kmlong to the cisterns. The water supply of the city including thethermeswastransportedthrougha150-m-longchannel withdimensionsof1.52.0 m2.Theadvancedwater-supplytech-nologiesdevelopedinMinoanCretewereexpandedandim-provedduringthe Romandominationof theGreekworld.Two suchexamples witha relatively small but impressivecistern in Minoan city and one of the two huge cisterns(of about 3000m3each) in Aptera city in the western Crete areshowninFigures5(c)and5(d),respectively.Duringtheclassical age(theperiodbetweentheArchaicand Roman epoch), the political situation was characterized inthe Greek world(mainly Greece andAsia Minor) by warsamongthevariouscities. Inthisperiod, nospringsor deepwells existed, socisterns wereconstructedtocollect rainfallduringthe winter season. These cisterns weredugintotherockandweremostlypear-shapedwithat least onelayerofhydraulic plaster that prevented water loss. The cisterns variedinsizefrom10 m3tothousandsofcubicmetersand possiblysupplied more than 10000-people baths and thermes. Topreventcontaminationofwaterthemouthofthecisternwascovered to keep out dust and debris, and to prevent light fromentering,avoidingthegrowthofbacteriaandalgae.Reservoirs constructed by the ancient Romans were setlow in theground,or actually underground,and roofedover,bymeansof concretevaulting. Theroongvaultsweresup-portedbyrowsofcolumns,piers,orwallpiercedwithdoorstoallowthewatertocirculate. Insomecases, theoor wasslightly concave with a drain in the middle, to permit cleaning(Hodge,2002;DeFeoetal.,2010).Ingeneral,intheRomanworldthereservoirs had two functions:a reservoir couldbe areservefor usewhentheaqueduct ranlowor byaddinginalittlefromthetankeverydaytosupplement suppliesuntilthe aqueduct discharge picked up again. When the dailyconsumptionexceededwhat theaqueduct couldbringin, atleast inthehours of daylight, thereservoir was toppedupeverynight tomeet thenext days demands (Hodge, 2002;DeFeoetal.,2010).An example of a Roman reservoir is the Bordj Djedidat Carthage inTunisia, intowhichthe Carthage aqueductemptiedafterarunofnolessthan90.43kmfromitssource.This great reservoir was oblong, 39.0 154.6 m2, the size of anentirecityblock,andsubdividedinto18transversecompart-ments. Itscapacitywas2500030000m3,representingaboutadayandahalfsdischargefortheaqueduct (Hodge, 2002;De Feo et al., 2010). Remaining in Tunisia, in the center of thecity of Dougga/Thugga, there are twovery large reservoirs.TherstoneistheAinElHammanreservoirwithveaisles,whilethesecondoneistheAinMizebreservoir withsevenaisles.Thetworeservoirshaveacombinedstoragevolumeof15000 m3(Tolle-Kastenbein, 2005; De Feo et al., 2010). Largereservoirs wereconstructednot onlyinNorthernAfricabutalsoinEurope,especiallyinItalyandinTurkey.Since a Roman thermae required an enormous quantity ofwater for its functioning, a huge reservoir hadtobe con-structed. As a matter of fact, the reservoir of the Baths ofCaracalla(locatedinanareaofover100 000m2)couldcon-tainover80 000m3inthenumerouscells, situatedintotwoparallel aisles and onto two oors. The oldest baths of Traianoreceivedwater supplyfromareservoir of around10000 m3(Tolle-Kastenbein,2005;DeFeoetal.,2010).ThegreatestbathsofDiocletianoccupiedaboutthesamearea as those of Caracalla (a rectangle of about 356316 m2)andclosely resembledtheminthe plans. The reservoir bywhich the baths were supplied was fed by the aqua Marcia, thevolumeof whichwasincreasedbyDiocletian. It wastrape-zoidal in shape, 91 m in length, with an average width of 16 m.This reservoir, called Botte di Termini (Barrel of Termini), wasWater and Wastewater Management Technologies in the Ancient Greek and Roman Civilizations 9destroyedduring1876inordertobuildtheTermini railwaystation, whosenamederivesfromthat of thebaths(DeFeoetal.,2010).In the three centuries of the Roman imperial age, thereservoirsweredesignedinalmostallthearchitecturalformsandinalmost all the techniques of masonry known: arcs(especiallytransversal arcs), turned(especiallybarrel vault),carrying pillars or groups of pillars, walls of stones and bricks,opuscaementicium;whilecolumnswerestillnotused.Infact,thecolumns wereintroducedbyarchitects famous for theirworks of hydraulic engineeringinthepresent-dayIstanbul.Theycreatedahost of columns hiddenintheheart of thecapital of the Roman Empire (Tolle-Kastenbein, 2005; De Feoet al., 2010). As a matter of fact, the name of the rst reservoirmeans with a 1001 pillars. It is the Binbirdirek reservoir whichwas built under the order of Philoksenos, a Senate member intheConstantinusI periodof thefourthcentury. DuringtheRomanperiod, Istanbuls water requirements were met bywater brought fromdistant partsof Thrace. For thisreason,the Byzantines built large reservoirs inorder tobe able towithstandlongsieges(DeFeoetal.,2010).TheBinbirdirekreservoircoveredanareaof3640 m2andhada capacity of around32 500m3of water. It measured66 56 m2andwas carriedby 224columns consisting of16rows, eachonehaving14columns,allofwhichareequalin length, and every column carries the signature of its master(1001 was used to emphasize the great number of columns).There is a thick overlapping astragal running round thecolumns carryingthevaults andarches andtheyareintheformof a truncated pyramid and are without decoration.Thereliefcrossononeofthecolumnsisgoodproofthatthereservoirwasbuiltinthefourthcentury, aftertheByzantinesacceptedChristianity.Inordertoconstructceilings1415m2high, asecondlayer of columns was xedover themarblerings onthe rst layer of columns. Whenthe palace wasdestroyedinthesixthcentury, thecisternwasrestored. Afterthe Ottomanconquest of Istanbul in1453, newreservoirswerebuilt andtheBinbirdirekwasnolonger used(DeFeoetal.,2010).One of the magnicent historical constructions of IstanbulistheYerebatanSaray(orBasilicaCistern), locatednearthesouthwest of Ayasofya (Hagia Sophia). This huge reservoirwas rebuilt by the emperor Justinian (527565) after the Nikarevolt (532). It is a large, vaultedspace; the roof rests on12rows of 28marblecolumns, whichareabout 9 mhigh.Asthetotal surfaceis65 138 m2, themaximumcapacityisalmost 85000m3, whichwas brought tothis cisternfroma well B20kmaway witha newaqueduct, also built byFigure 5 Minoan, Hellenistic, and Roman water collection and storage cisterns: (a) Minoan at the ancient town of Tylissos; (b) Hellenistic at the city ofEleutherna; (c)Roman atthe Minoa town; and (d) Roman attown of Aptera. Copyright permission with ANAngelakis.10 Water and Wastewater Management Technologies in the Ancient Greek and Roman CivilizationsJustinian.Itwasusedtoprovidewatertotheimperialpalace(hence the name, imperial cistern). The 336 columns (246 arestill visible)werebrought totheBasilicaCisternfromolderbuildings. Again,itis narratedthat7000 slaves worked intheconstructionof thecistern. Infact, thecisternborroweditsname fromIlius Basilica inthe vicinity (Lendering, 2008;Ku ltu r,2008;DeFeoetal.,2010).Another huge Roman reservoir in ancient Constantinopolis(todaysIstanbul)istheSultansCistern.Wedonothaveanyveriablescienticevidencefor its constructiondate; at theearliest, it couldbelatefourthcenturyAD, judgingbythepresenceofcrossescarvedintothe upperpartsofthe columnheads. It has a rectangularplan and the wholeis dividedintove equal rectangular parts by the use of 28 columns, with 7 ingraniteand21 inmarble,placedequidistantfromeachother,alsosupportingtheroof withvaultedarches(DeFeoet al.,2010).The last Roman underground hydraulic marvel is thespectacular Piscina Mirabilis inMisenum, inthe SouthernItaly. ThePiscinaMirabilisislocatedinthepresent-dayMu-nicipality of Bacoli, in Miseno (the ancient Misenum),up thehill facingtheseainthebayof Naples. It was constructedduring the AugustanAge inorder to supply water to theClassis Praetoria Misenensis (Adam, 1988; Hodge, 2002;DeFeoandNapoli, 2007; DeFeoet al., 2010). ThePiscinaMirabilis is a gigantic reservoir 72 m long and 27 m large, withavolumetriccapacityof 12 600m3of water(Figure6). It isdug in a tufa hill and has two step entrances in the northwest,theAncientRomanentranceandsoutheastcorners,thelatterclosed. Forty-eight pillars, arrangedonfour rows servingasa support to the barrel vault, divide it into ve principalaisles on the long sides (Figure 7(a)) and 13 secondary aislesontheshort sides(Figure7(b)), givingit themajesticlookof acathedral. Thelongwalls werebuilt inopus reticolatum(reticularwork)withbrickbondingcoursesandbythetech-nique of the tufa stone pillars, bothcoveredwitha thickwaterproof layerof opussigninum(poundedterracotta).Thereis abasinof 1.10m, probablyapolishingpool, whichis awaste bath for the maintenance of the reservoir, in the oor ofthenave. It wasusedasaPiscinalimariafor theperiodicalcleaningof thereservoir (Figure7(c)). Thewater wasliftedthroughaseries of openings (doors)inthevault alongthecentral nave, hydraulicallytothecoveringterraceof theres-ervoir,andfromthere,owedinchannelstotheurbanarea.These doors appear casually opened in the roof (Figure 7(d)),with an irregular realization being noted (Adam, 1988; Hodge,2002;DeFeoandNapoli,2007;DeFeoetal.,2010).Russo and Russo (2007) estimated a total daily demand of12000 m3of waterfor Misenum, including4000 m3for theeet and 8000m3for daily demands and for the thermal bathsand gardens (based upon daily individual requirements of 100liters per capita and equal requirements for thermal baths andgardens). Theestimatedtotal dailydemandissimilartothecapacity of the Piscina Mirabilis. Close to the Piscina Mirabilisare two other large cisterns, probably belonging to large villas,theGrottaDragonariaandCentoCamerelle(Neronesjail).InPozzuoli, theaqueductservedseveralcisterns,notablythePiscina Cardito(55 16m2) fromthe secondcentury, andthePiscinaLusciano(35 20m2)fromtherst centuryAD(DeFeoandNapoli,2007;DeFeoetal.,2010).4.01.5 Water Distribution SystemsWater distribution systems are aimed at distributing waterfromreservoirs or aqueducts totheendusers. Themodernsystemsarebasedontheuseofpipes. Regardingthisaspect,theMinoansocietywassurprisinglymodern. Asamatteroffact, in the Knossos palace, the water supply was furnished bymeans of a networkof terracotta pipe conduits (6075 cmangedtot intooneanother andcementedat thejoints)beneath the oors at depths that vary from a few cm up to 3 m(Koutsoyianniset al., 2008; AngelakisandSpyridakis, 2010).Possibly, the piping systemwas pressurized (Mays, 2007).Similar terracotta pipes were discovered in some other Minoansites.Inparticular,TylissoswasoneoftheimportantcitiesinAncientCreteduringtheMinoanera,ourishing(20001100BC)asaperipheral centerdependent onKnossos. Fromtheaqueduct,secondaryconduitswereusedtoconveywatertoasedimentation tank (Figure 8; Mays, 2010) constructed ofstonebeforeitsstoragetothecisternshowninFigure5(a).Terracotta pipes have also been found at Vathypetro, as well asin the Caravanserai (Guest House), south of the Knossospalace withsome alsohaving beenfoundscatteredinthecountryside(AngelakisandSpyridakis,2010).Thestudyof theruins of Pompeii givesaclearer under-standing of a Roman urban water distribution system. But thisstatement does not mean that all Roman cities are identical toPompeii. The ending point of a Romanaqueduct was thecastellumdivisoriumwhichhadthedoublefunctionofservingasadisconnectionbetweentheaqueductandtheurbandis-tribution network as well as dividing the water ow to varioususesand/orgeographicalareasofthecity(Figure9).Inthebeginning,Pompeiiwas notsuppliedby theSerinoaqueduct. As there were no springs in Pompeii, wells were dugtosupplywater. It is alsoverylikelythat Pompeii receivedwaterviaanaqueduct fromthemountainsduenortheast ofAvella. The town must have had a long-distancewater supply,quite some time before the Augustan Age, probably around 80BC. Whenthe Serinoaqueduct was built under Augustus,it crossed the course of the older Avella aqueduct between theApennines andMount Vesuvius, andbothaqueducts wereunitedintoasinglesystem(DeFeoandNapoli,2007).The castellumdivisoriumof Pompeii was housed insidealargebrickbuildingnear theVesuviangate(Figure10(a)).The supply channel entering the building is 3025cm(Figure 10(b)). The owinthis distributionstructure wasallowedtoexpandintoawide, shallowtank, separatedintothree equal compartments (masonry structures) (Figure 10(c)).Flowfromeachcompartment enteredaleadpipe. Somefeelthatthethreepipeswereconnectedseparatelytopublicfoun-tains,thesecondtothethermalbathsandthethirdtoprivateusers (Hodge, 2002; Russo and Russo, 2007). From the exits thewaterowedintoleadpipes. Thereisalsothedistinct possi-bility that the three pipes were directed to different geographicalareas of Pompeii. Assumingthat thepipes didconveywaterseparately to the three major uses as presented by Hodge(2002), thecentral pipewasdirectedtothepublicfountainsandhada30cmexternaldiameter,whereasthetwosideoneswere 25cmin diameter. The three gates were of differentheights. Thus, thehighestgate,whichwasthatservingprivatehouses, cut off their supplies until and unless the water level inWater and Wastewater Management Technologies in the Ancient Greek and Roman Civilizations 114.31.2 4.94.94.34.34.34.34.34.34.34.34.34.34.91.21.21.21.21.21.21.21.21.21.21.21.21.21.24.9 4.0 4.0 4.0 1.2 1.2 1.2 1.2 1.210.4 1.29.42.01235A41Inlet waterAncient Roman entrance - 2Ancient Roman entrance - 1Piscina LimariaOutlet washing waterLegendPlan of the Roman Piscina MirabiliisLongitudinal section A-AA2 3 4 5ABBTrasversal section B-B( Measures in meters )11.411.43.01.272.027.0NFigure 6 Plan and sections of the Piscina Mirabilis.Modied from De FeoG, DeGisi S, Malvano C, and DeBiase O(2010) The greatest waterreservoirs in theancient Roman world and the PiscinaMirabilis inMisenum. Water,Science and Technology: Water Supply 10(4) (in press).12 Water and Wastewater Management Technologies in the Ancient Greek and Roman Civilizationsthe main body of the castellum rose high enough to spill over itand start owing down the channel; on the contrary, the lowestgate (that in the center) governed access to the public fountains,which, if thewaterlevel sank, werethustheleast todryup.The private users had no minimum water entitlement until theneeds of the public fountains andthermal baths hadbeensatised(Hodge,2002).From the castellum divisorium, the three pipes lead the watertodifferentpartsofthecityllingwatertowers:thecastellumsecondariumor castellumprivatum(Figure10(d)). Thewatertowers wereleadtanks positionedontopof brickmasonrypillars, 6mtall, locatedat crossroadsandconnectingsmallnumbersof customers. Theyalsosuppliedpublicfountains.Thesingleuserhadtopaytoobtainwaterforhispremises.The water was metered by means of bronze orices, the calicesconnectingthecustomers pipes (usuallyquinariaepipes)tothecastellumprivatumleadtank.In Pompeii, casecaliceswereplacedat the bottomof the leadtanks, andpipes t intocavities left inthe brick pillars (Hodge, 2002; Monteleoneetal.,2007).Figure 7 Piscina Mirabilis: (a)a cross aisle;(b) alongitudinal aisle;(c) internal piscina limaria; and (d)a holein the barrelvaultedroof.Water and Wastewater Management Technologies in the Ancient Greek and Roman Civilizations 13Theleadtank onthewatertoweracted asadisconnectionbetweenthesystemat highpressureupstreamandthecus-tomers pipes downstream. Connecting water derivation pipeselsewhere in the castellum privatum was against the regulations.Theonlyconnectionavailablehadtobearrangedwiththewater ofcediscussingthequantities for consumption. Thiswater-supply systemclearly shows that water towers couldbreak from the pressure built up in the mains descending fromthe initial castellumdivisoriumat the toppoint of the city,withexcess water overowingintostreets drains. As showninFigure9, themaximumheight of wateroverthetapwasabout 6m, without accountingforthepressurelossesinthedeliveringpipes(Hodge,2002;Monteleoneetal.,2007).Leadpipes (Figure11)inPompeii areof thesamecon-struction and appearance as found in other Roman cities. Thewater taps found in Pompeii were also similar to those foundinother Romancities. Onlyasmall number of houseshada water pipe that supplieda private bathor basins inthekitchen,inthetoilet,orinthegarden.4.01.6 FountainsThe Minoan civilization gave an extraordinary contribution tothe development of water management practices also in termsof fountains. The mainexamples of Minoanfountains aresubterraneanstructuressuppliedwithwater directlyorfromsprings via ducts. The construction of steps or alternatively theshallow basins indicates that water was taken out with the useof acontainer. Thisrecalls thetypeof fountainof thelaterClassical and Hellenistic period called arykrene. The mosttypicalofthemisthatoftheZakropalace.AnotherfountainsimilartotheTyktewasfoundattheGuestHouse(Caravan-serai)ofKnossosintheSpringChamber.AritualfunctionofAqueductHead18 m CastellumdivisoriumCastellumsecondariumHead6 m Figure 9 Flow sheet of a Roman urban water distribution systems based on Pompeii. Modied from Hodge AT (2002) Roman Aqueducts &WaterSupply,2nd edn. London: GeraldDuckworth.Figure 8 Water system atTylissos, Crete, Greece with sedimentationtank inforeground with stonechannel connecting tocistern inbackground.(Mays, 2010,Copyright permission withLW Mays).14 Water and Wastewater Management Technologies in the Ancient Greek and Roman Civilizationsthe particular fountains is alsoargued, as artifacts of ritualcontent have also been unearthed. Another type known in laterperiods as rookrene, which constantly provided freshwater,wasalsofoundinZakrowithtwozoomorphicwaterspouts.Finally, a remarkable fragment froma fresco compositiondepicting a fountain of a supposedly Minoan gardenwasfoundintheHouseof Frescoes inKnossos (Angelakis andSpyridakis,2010).DuringtheRomanperiod, publicfountainswereusuallylocatedinthestreet. For example, inPompeii thefountainswerelocatedatfairlyevenlyspacedintervalsofabout100 m,anditwasrareforanyonetocarrytheirwaterformorethan50m (Hodge, 2002). The simplest form of street fountain wasnormally equipped with an oblong stone basin, typicallyabout 1.51.8 m2and 0.8mhigh, into which the spoutdischarged, andwhichpresumably was normally full. Thefountainsweredeliberatelydesignedtooverowinordertocleanthestreet(Hodge,2002;DeFeoetal.,2010).Not far from the city of Pompeii, in the District of Salerno,thereisaRomangalleryinrockinthevillageofSantEgidiodel MonteAlbinointheSarnoRiver basin. Thegallerywasconstructed in order to supply a public fountain which standson the structure of an ancient Roman villae (the Helviusvillae). The Helvius fountain was a public fountain, but it wasquitedifferent fromthepublicfountainsinnearbyPompeii(Figure12(a)). Asamatteroffact, theHelviusfountainwasconstructedneitherbymeansof matchedslabsnorinlime-stonenorinVesuvianstone. Itwasbuiltasasingleblockofwhite marble. Moreover, there is another particular aspectwhichdifferentiatestheHelviusfountainfromthePompeianfountains(Figure12(b)). TheHelviusfountainhasasculp-tural decoration on the three available sides representingtheriverSarnoalongitspathfromthespringtowardthesea(DeFeoetal.,2010).Figure13showstwoadditionalRomanfountainsthatarequite different from those previously mentioned. Figure 13(a)shows a fountain in Chersonesos (Crete) and Figure 13(b) theFountain of Trajan in Ephesus (Turkey), dedicated by Aristion,AD102/114.4.01.7 Drainage and Sewerage Systems and ToiletsDrainagesystemswereusedforthedisposalofsurpluswater,and were found both in cities (to carry rainfall, overow fromfountains andbathrooms) andinthe country (topreventFigure 10 Pompeii: (a) brick building near the Vesuvian gate housing the castellum divisorium; (b) inside castellum divisorium; (c) supply channel;and (d) acastellum secondarium.Water and Wastewater Management Technologies in the Ancient Greek and Roman Civilizations 15oodingintheelds). Seweragesystems wereusedfor theconveyanceofdomesticwastewater, andwereonlyfoundincities, where theywerenecessaryduetoahighpopulationdensity (Hodge, 2002). However, inmost cases, combinedsystemsofowratescomposedmainlyofrainfallrunoffandwastewaterwereapplied.TheMinoancivilizationalsogaveanextraordinarycon-tribution to the development of water management prac-tices in terms of drainage and sewerage systems. As a matter offact, Minoan palaces were equipped with elaborate stormdrainage and sewer systems (MacDonald and Driessen, 1988).Openterracottaandstoneconduitswereusedtoconveyandremove stormwater and limited quantities of wastewater.Pipes, however, were scarcely usedfor this purpose. Largersewers, sometimes large enough for a man to enter and clean,were used in Minoan palaces at Knossos, Phaistos, and Zakro.These large sewers may have led to the conception of the ideaof thelabyrinth, thesubterraneanstructureintheformof amazethathostedtheMinotaur,ahybridmonster.The end section of the main part of the sewerage system ofthe Knossos palace is shown in Figure 14(a). The outlet of thePhaistos palacesystemappears tobesimilar (Figure9(b)).Notethat Evans (192135) andDarcqueandTreuil (1990)considered that the main part of the system had been plannedandconstructedoriginallyinMiddleMinoantime.Themaindisposal sites at the Knossos and Zakros palaces were directedFigure 11 Components oflead pipe system found in Pompeii:(a) lead pipe and joint found along the street; (b)junction box; and (c) manifold.Copyright permission withLW Mays.16 Water and Wastewater Management Technologies in the Ancient Greek and Roman Civilizationstothe Kairatos River andtothe sea, respectively. However,thereareindicationsthatinthepalaceofPhaistosandinthevilla of Agia Triadha, cisterns were also used as disposal sites ofsurfacewater, alongwithappropriatelandforms. Particularlyin the palace of Phaistos, agricultural land located in the southsiteof thepalacewas usedas disposal siteof theboththewastewater andstormwater insteadof theriverIeropotamoscrossingthenorthernsiteofthePhaistoshill. Inall casesofpalaces andcities, thereisanincreasedslopeof thecentralsewers toward of their outlets; thus, anaerobic conditions havebeenmaintainedandtheodorshavebeenavoided.Inadditiontothe very effective drainage andseweragesystems, some palaces had toilets with ushing systemsoperatedbypouringwater inaconduit. However, thebestexampleof suchaninstallationwasfoundontheislandofThera(Santorini) intheCyclades, Greece. This is themosteloquent andbest-preservedexamplebelongingtotheearlylate-Minoan period (c. 1550BC) in the Bronze Age settlementof Akrotiri, whichshares thesamecultural context of Crete(AngelakisandSpyridakis,2010).At thebeginning, for somecenturies, thecollectionanddischarge of rainwater runoff was managed by separate sewers.Asamatteroffact, rainwaterwascarriedinsimplechannelscarved intotherockincitieswithbedrock(i.e.,theAcropolisofAthens).Otherwise,thechannelswerecoveredwithrocks.Asystemfor the simultaneous discharge of bothrainwateranddomesticsewagewasinventedduringtheGreekperiod(Tolle-Kastenbein,2005).Ancient drainage and sewerage systems were usuallydevelopedonfour levels. Theinitial channels comingfrombuildings (rst order) ended in street channels of secondorder, which prosecuted in principal channels with an increas-ingsize(thirdorder) andendedinanal hugecollectionchannel(fourthorder),usuallypresentonlyinbigcities.Thegreat drain of Athens was rst designed as a rainwater drainagesystem. However, intherst quarterof thefthcenturyBC,it receiveddomesticsewageandendedinahugecollectionchannel(fourthorder)similartotheRomanCloacaMaxima(Tolle-Kastenbein,2005).The Cloaca Maxima is the best-known ancient urban drain.TraditionascribesitsconstructiontoTarquiniusPriscus,kingof Rome616578 BC. The Cloaca Maxima (4.2m high,3.2 mwide) was coveredbystonevaulting, whileits bottomwaspavedwithbasaltpavers. ItcombinedthethreefunctionsofFigure 12 Publicfountains: (a) inPompeii (matched slabs) and (b)in the basinof the Sarno river(single blockof white marble).Figure 13 Roman fountains: (a) fountain in Hersonissos (Crete) and (b) remains of the fountain of Trajan in Ephesus (Turkey), dedicated by Aristion,AD, 102/114. Copyright permission with LW Mays.Water and Wastewater Management Technologies in the Ancient Greek and Roman Civilizations 17wastewaterandrainwaterremovalandswampdrainage.Asitis well known, the exit from the Cloaca Maxima drain into theriverTiberstillexistsinRome,butnowpartlyhiddenbythemodernLungotevereEmbankment(Hodge,2002).The street drains of Pompeii are very famous. At the time ofthefamousVesuviuseruption, thedrainsexistedonlyinthearea around the forum. The streets were a sort of open channelconveying water coming frompublic fountains, rainwater,and segregate sewage. Therefore, as shown in Figure 15, streetshadraisedsidewalks (5060 cmhigh) withsteppingstones(pondera)at thestreet cornerstoenablepedestrianstocrossfromonesidetotheother without steppingdown(Hodge,2002).Toiletshavealonghistory. Therst evidenceof thepur-poseful construction of bathrooms and toilets in Europecomes from Bronze Age Minoan (and Mycenaean) Crete in thesecondmillenniumBC(Vuorinenetal.,2007). Inthepalaceof Knossos, rainwater was probablyusedtoushthetoiletneartheQueensHall(Figure16;Angelakisetal.,2005).TheHellenisticperiodisconsideredmoreprogressiveforthesanitaryandpurgatoryengineeringduringtheantiquity,although the considerable spreading of these systems occurredduringtheRomanera. TheRomansappliedtheearliertech-niquesinlarger constructions, usingtheadvantagesof theirbuilding methods withconcrete walls andvaultedroong.Moreover,duetotheirimprovedaqueducttechnologies,theycouldprovidenaturalwaterowinmostpubliclatrines.Itisalsoevident that suchstructures andinstallations havesur-vived until the end of the ancient world and have beenimplementedduringthebeginningof theByzantineperiod.Thecustomsofthenewreligion,Christianity,modiedsomeof the structures in terms of privacy in bathing facilities(AntoniouandAngelakis,2009).During the Hellenistic era lavatories improved signicantly,followedbytheirspreadthroughouttheRomanEmpire.Thefeatures of the typical ancient lavatory are the bench-type seatswithkeyhole-shapeddefecationopeningsandanunderneathditch.Theditchwas botha water-supply conduitforushingandasewer. Figure17shows remains of apublictoilet inEphesus (Turkey) illustratingthebenchseats, thedefectionopenings, and the small channel on the oor for cleaning thesponghia. Thelavatorywasusuallysituatedintheareaofthebuildingmost convenient forwatersupplyand/orsewerage.Inmanycases, thewater for theushingwas reusedeitherafterotherdomesticorcommunal activities. Despiteprivacy,lavatories were used in antiquity by many people simul-taneously, fromtwotothree people inthe small domesticlatrines andup to60 people inthe larger public latrinesFigure 14 Outlet of the central Minoan sewerage and drainage systems: (a) palace of Knossos and (b) palace of Phaistos. Copyright permission withAN Angelakis.18 Water and Wastewater Management Technologies in the Ancient Greek and Roman Civilizations(Antoniou, 2010). Lavatories were used throughout theRoman Empire, with a more or less monumental appearance.ThereaderisreferredtoAntoniou(2010)foradetaileddis-cussionofancientGreeklavatories.Toilets during the Romanera canbe dividedinto twogroups: public and private. A public toilet was frequently builtnear to or inside a bath so that it was easily entered from bothinsideandoutsideofthebath. Theabundanceofwaterthatwas conductedtothebathcouldalsobeusedtoushthetoilet. Pipedwater for ushingprivatetoiletsseemstohavebeen a rarity. The Romans, however, lacked something similartoourtoilet paper. Theyprobablyusedspongesormossorsomethingsimilar. Inpublictoilets, thefacilities werecom-mon to all. They were cramped, without any privacy, and hadnodecentwaytowashoneshands. Theprivatetoiletsmostlikelylackedrunningwaterandtheywerecommonlylocatednear the kitchens. All this created an excellent opportunity forthespreadingofintestinalpathogens(Vuorinenetal.,2007).Hygienicconditionsinbothtypesof toiletsmust havebeenverypoor,andconsequentlyintestinaldiseaseswere diffused.Dysentery, typhoidfever, anddifferentkindsofdiarrheasarelikely candidates for diagnoses. Unfortunately, descriptions ofthe intestinal diseases in the ancient texts are so unspecic thattheidenticationofthecausativeagentisaveryproblematicventure. Studiesofancientmicrobial DNAmightoffersomenewevidence for the identicationof microbes spreadbycontaminatedwater(Vuorinen,2010).4.01.8 Discussion and ConclusionsInthe Minoan, Greek, andRomancities, andother settle-ments, water supply varied according to local conditions,determinedbyclimate(mainlyrainfall), surfaceandgroundwater, and terrain. In these periods, various water-supplyand wastewater systems and techniques were developedand applied, such as collection and storage facilities, wells andgroundwater abstraction aqueducts, water distribution anduse, constructionanduse of fountains, sewers, bathrooms,and other sanitary facilities and even recreational uses ofwater. Theseadvanced technologies, whichhave beenusedinprehistoric Crete since about 4500 years ago, were sub-sequently expanded during the Mycenaean and then theArchaic, Classical, andRomanperiods. Inlight of thesehis-torical and archaeological evidences, it turns out that theprogressofpresent-dayurbanwaterandwastewatertechnol-ogies as well as comfortable andhygienic living is not assignicant as we tend to believe (Angelakis and Koutsoyiannis,2003). However, a burst of achievements in water andDoorjambWoodenseatGypsum floorFlushingconduitDoorsSewerSeatSewer1 mHoodFigure 16 Section and plan ofground-oortoilet inthe residentialquarter ofpalaceof Minos. From Angelakis AN, KoutsoyiannisD, andTchobanoglousG(2005) Urban wastewater and stormwatertechnologies inancient Greece. WaterResearch39: 210220.Figure 15 Stepping stones (pondera) inPompeii.Water and Wastewater Management Technologies in the Ancient Greek and Roman Civilizations 19wastewater technology was accomplished throughout thecenturies of the ancient Greek and Roman civilization. With afewexceptions, the basis for present-day progress inwatertransferisclearlynotarecentdevelopment,butanextensionandrenementofthepast.Infact,thesurprisingfeaturesarethesimilarityof ancient water methodologies withthoseofthepresent andtheadvancedlevel of water andwastewatermanagementusedbytheancients.Greek andRomantechnological developments inwaterandwastewatermanagementprinciplesandpracticesaswellas other achievements of thosecivilizations, suchas poetry,philosophy,sciences,politics,andvisualarts,arenotknown.To put in perspective the ancient water and wastewaterachievements discussed in this chapter, it is important toexamine their relevance to modern times and to harvest somelessons. Therelevanceof ancient hydraulicworksshouldbeexaminedintermsof theevolutionof technology, thetech-nological advances, homeland security, and managementprinciples.The Romans, whose empire replacedthe Greek rule inmost part of this area, inherited the technologies anddevelopedthemfurther bychangingtheir applicationscalefromsmall tolargeandimplementingthemtoalmosteverylargecity. TheGreekandRomanwatertechnologiesarenotonly a culturalheritagebut alsotheunderpinningofmodernachievements in water and wastewater engineering andmanagement practices. Apparent characteristics of technolo-giesandmanagementpracticesinmanyancientcivilizationsaredurabilityandsustainability. Also, therehavebeeninte-grated management practices, combining both large-scale andsmall-scale constructions and measures that have allowedcitiestosustainformillennia.Currently, engineers use returnperiodfor the designofhydraulicstructuresasdictatedbydesignstandardsandeco-nomic considerations. Sustainability, as a design principle, hasenteredtheengineeringlexiconwithinthelast decade. Nat-urally, it is difcult to estimate the design principles of ancientengineers but it is notable that several ancient works haveoperated for very long periods, some until recent times. Thus,wastewater and stormwater drainage systems were functioninginBronzeAgesettlements andcontinuedduringtheGreekand Roman periods. These include the construction and use ofbathroomsandothersanitary andpurgatoryfacilities,aswellaswastewaterandstormsewersystems.Infact,thehydraulicandarchitectural functionof sewer systems inpalaces andcities are regarded as one of the salient characteristics ofMinoancivilization. Theyweresoadvancedthattheycanbejustlycomparedwiththeirmoderncounterparts.Thedurabilityofsomeoftheconstructionsthatoperatedup to present times, as well as the support of the technologiesand their scientic background by written documents, enabledthesetechnologiestopasstopresentsocietiesdespiteregres-sions that have occurredthroughthe centuries (i.e., intheDarkAges). Thedevelopment of scienceandengineeringisnot linear but often characterized by discontinuities andregressions. Bridges fromthe past tothe future are alwayspresent, albeit oftentimes they are invisible to those who crossthem!Thus, inadditiontomanyancient constructionsthathave been continuously or intermittently in operation to date,substantial information fromancient Greek and Romanwrittensourceshasalsobeenpreserved(AngelakisandKout-soyiannis,2003). Thus,themajorachievementswereaccom-plished during the Greek and Roman civilizations. As a result,theyrepresentthestate-of-the-artstructuresthatweretechni-cally feasible at that time. For example, the aqueduct ofancient Samos, called&mj istomon or bi-mouthed (thuspointing out that it was constructed from two openings), is animportant hydraulic monument, indicatingthat it was pos-sibleintheancient worldtodesignandconstruct technolo-gically advanced water transportation projects on a large scale.Figure 17 Public toilet in Ephesus (Turkey): (a) the bench-shaped seats were constructed of stone slabs with another vertical stone slab that coveredthe opening from the void between the oor and the seat and (b) the small channel (half-pipe-shaped cross-section) on the oor in front of the seathad a continuous ow of water forcleaningthesponghia(the toilet paper ofthe time). Copyright permission withLW Mays.20 Water and Wastewater Management Technologies in the Ancient Greek and Roman CivilizationsFromthe preceding synoptic discussion, certainconclu-sionsmightbesuggestedforfurtherreectionandsystematicinvestigation:1. The water andwastewater hydraulics works inMinoan,Greek, and Romancivilizations are sometimes not toodifferentfromthemodernpractice,sincepresenttechnol-ogiesdescenddirectlyfromthattimesengineering.2. Minoan, Greek, andRomanwaterandwastewaterpublicworksarecharacterizedbysimplicity, robustnessof oper-ation,andtheabsenceofcomplexcontrols.3. The meaning of sustainability inmoderntimes shouldbe reevaluated in light of Minoan, Greek, and Romanhydraulic works andwater andwastewater managementpractices.4. Technological developmentsbasedonsoundengineeringprinciplescanhaveextendedusefullives.5. Inareasofwatershortage,developmentofacost-effectiveandenvironmental friendlywater resources managementpractice, based on Minoan, Greek, and Roman civilizationsprinciples,isessential.ReferencesAdamJP(1988)LArtediCostruirepressoi Romani. Materiali eTecniche(RomanBuilding: MaterialsandTechniques). Milan: Longanesi.AngelakisANandKoutsoyiannisD(2003)Urbanwaterresourcesmanagement inancient Greektimes. In: Stewart BAandHowell T(eds.)Encyclopediaof WaterScience, pp. 999--1007. NewYork: Dekker.AngelakisAN, KoutsoyiannisD, andTchobanoglousG(2005)Urbanwastewaterandstormwatertechnologiesinancient Greece. WaterResearch39: 210--220.AngelakisAN, LyrintzisAG, andSpyridakisSV(2010)Urbanwatermanagement inMinoanCrete, Greece. E-Water(inpress).AngelakisAN, SavvakisYM,andCharalampakisG(2007)AqueductsduringtheMinoanera. WaterScienceandTechnology:WaterSupply7(1): 95--101.Angelakis AN and Spyridakis SV (1996) The status of water resources in Minoan timesapreliminarystudy. In:AngelakisAandIssarA(eds.)DiachronicClimaticImpactsonWaterResourceswithEmphasisonMediterraneanRegion,pp. 161191. Heidelberg: Springer.AngelakisANandSpyridakisDS(2010). Watersupplyandwastewatermanagementaspectsinancient Greece. WaterScienceandTechnology: WaterSupply10(4)(inpress).AntoniouG, XarchakouR, and Angelakis AN (2006)Water cisternsystems in GreecefromMinoantoHellenisticperiod.In: AngelakisADandKoutsoyiannisD(eds.)Proceedingsof 1st IWA International SymposiumWaterandWastewaterTechnologies in Ancient Civilizations, pp. 457462. National Agricultural ResearchFoundation,Iraklio, Greece, 2830October2006.AntoniouGP(2010)Ancient Greeklavatories:Operationwithreusedwater. In:MaysLW(ed.)Ancient WaterTechnology.Dordrecht: Springer.Antoniou GP and Angelakis AN (2009) Historical development bathrooms (toilets) andothersanitaryandpurgatorystructuresinGreece. In: Proceedingsof 2ndIWAInternational SymposiumonWaterandWastewaterTechnologiesinAncientTechnologies.Bari, Italy, 2829May2009.Bersani P, CanaliniA,andDragoniW(2010)FirstresultsofastudyoftheEtruscantunnel and other hydraulic works on the Ponte Coperto stream (Cerveteri, Rome,Italy). WaterScienceandTechnology: WaterSupply10(4)(inpress).Bono P and Boni C (1996) Water supply of Rome in antiquity and today. EnvironmentalGeology27: 126--134.CadoganG(2007)Watermanagement inMinoanCrete, Greece: Thetwocisternsofone Middle Bronze Age settlement. Water, Science and Technology: Water Supply7(1): 103--112.CrouchDP(1993)WaterManagement inAncient GreekCities.NewYork: OxfordUniversityPress.DarcquePandTreuil R(eds.)(1990)Thestormdrainsoftheeast wingat Knossos.Special Issue: Lhabitat egeenprehistorique.BulletindeCorrespondanceHellenique, Supplement 19: 141146.DavarasK(1976)GuidetoCretanAntiquities. ParkRidge, NJ: NoyesPress.De Feo G, De Gisi S, Malvano C, and De Biase O (2010) The greatest water reservoirsin the ancient Roman world and the Piscina Mirabilis in Misenum. Water, ScienceandTechnology: WaterSupply10(4)(inpress).De Feo G, De Gisi S, Malvano C, et al. (2010) The Roman aqueduct and the HelviusFountaininSantEgidiodelMonteAlbino, inSouthernItaly: Ahistorical andmorphological approach. In: Proceedings of 2nd IWA International Symposium onWaterandWastewaterTechnologiesinAncient Technologies. Bari,Italy, 2829May2009.De Feo G, Malvano C, De Gisi S, and De Biase O (2009b) The ancient aqueduct fromSerinotoBeneventuminSouthernItaly: Atechnical andhistorical approach. In:Proceedingsof 2ndIWA International SymposiumonWaterandWastewaterTechnologiesinAncient Technologies. Bari,Italy,2829May2009.De Feo G and Napoli RMA (2007) Historical development of the Augustan aqueduct inSouthern Italy: Twenty centuries of works from Serino to Naples. Water Science andTechnology: WaterSupply7(1): 131--138.EvansSA(19211935)ThePalaceofMinosat Knossos: AComparativeAccount oftheSuccessiveStagesof theEarlyCretanCivilizationasIllustratedbytheDiscoveries,vols. IIV, London: Macmillan(reprintedbyBibloandTannen, NewYork,USA, 1964).FahlbuschH (2006)Water management inthe classiccivilization.In:ProceedingsofLaIngenieriaYLaGestionDelAguaaTravesdeLosTiempos. UniversidaddeAlicante, Spain, with the Universidad Politechnica de Valencia, Alicante, Spain, 30May01June2006.GorokhovichY(2005)Abandonmentof MinoanpalacesonCreteinrelationtotheearthquakeinducedchangesingroundwatersupply. Journal of ArchaeologicalScience32: 217--222.GrahamJW(1987)ThePalacesof Crete. Princeton, NJ: PrincetonUniversityPress.HabereyW(1972)DieromischenWasserleitungennachKoln. Bonn: Rheinland-Verlag.HansenRD(2006)Waterandwastewatersystemsinimperial Rome.http://www.waterhistory.org(accessedFebruary2010).HodgeAT(2002)RomanAqueducts&WaterSupply,2ndedn.London: GeraldDuckworth.KarakostantinouA(2006)TheRomanAqueduct of Moria, Lesvos. Volos,Greece:Department of ElementaryEducation, Universityof Thessaly(inGreek).KoutsoyiannisD, Mamassi N, andTegosA(2007)Logical andillogical exegesesofhydrometeorological phenomenainancient Greece. WaterScienceandTechnology: WaterSupply7(1): 13--22.KoutsoyiannisD, ZarkadoulasN,AngelakisAN, andTchobanoglousG(2008)Urbanwatermanagement inancient Greece: Legaciesandlessons. ASCE, Journal ofWaterResourcesPlanningandManagement 134(1): 45--54.KulturAS (2008)TheHistoryof theBasilicaCistern. Istanbul, Turkey. http://www.yerebatan.com/english/itarihce.html (accessedJuly2010).LenderingJ(2008)Constantinople(Istanbul): BasilicaCistern. Istanbul, Turkey.http://www.livius.org(accessedJuly2010).MacDonald CF and Driessen JM (1988) The drainage system of the domestic quarterinthePalaceat Knossos. BritishSchool of Athens83: 235--358.Martini P and Drusiani R (2009) History of the water supply of Rome as a paradigm ofwaterservicesdevelopment inItalicpeninsula. In: Proceedingsof 2ndIWAInternational SymposiumonWaterandWastewaterTechnologiesinAncientTechnologies. Bari, Italy, 2829May2009.Mavromati EandChryssaidisL(2007)AqueductsintheHellenicareaduringtheRomanPeriod. WaterScienceandTechnology: WaterSupply7(1): 139--145.Mays LW (2007) Ancient urban water supply systems in arid and semi-arid regions. In:Proceedingsof International SymposiumonNewDirectionsinUrbanWaterManagement. UNESCO, Paris, France, 1214September2007. KoreaWaterResourcesAssociation, http://www.kwra.or.kr(accessedFebruary2010).MaysLW(2008)Averybriefhistoryof hydraulictechnologyduringantiquity.Environmental FluidMechanics8(5): 471--484.MaysLW(ed.)(2010)Ancient WaterTechnologies.Dordrecht: Springer.MaysLW, KoutsoyiannisD, andAngelakisAN(2007)Abrief historyof urbanwatersupplyinantiquity.Water, ScienceandTechnology: WaterSupply7(1): 1--12.MonteleoneMC, YeungH, andSmithR(2007)Areviewof ancient Romanwatersupply exploring techniques of pressure reduction. Water Science and Technology:WaterSupply7(1): 113--120.MyersJW,MyersEE, andCadoganG(1992)TheAerial Atlasof Ancient Crete.Berkeley,CA: Universityof CaliforniaPress.OzizU(1987)Ancient waterworksinAnatolia. WaterResourcesDevelopment 3(1):55--62.OzizU(1996)Historical waterschemesinTurkey. WaterResourcesDevelopment12(3): 347--383.Panimolle G (1984) Gli Acquedotti di Roma Antica (The Aqueducts of Ancient Rome).Rome: Edizioni Abete.Water and Wastewater Management Technologies in the Ancient Greek and Roman Civilizations 21RodgersRH(2004)SextusIuliusFrontinus.OntheWater-Management of theCityof Rome.DeAquaeductuUrbisRomae. Cambridge: CambridgeUniversityPress.RussoFandRussoF(2007)Pompei. LaTecnologiaDimenticata(Pompeii. TheForgottenTechnology). Naples: ESAEdizioni ScienticheeArtistiche.Tassios TP (2007) Water supply of ancient Greek cities. Water Science and Technology:WaterSupply7(1): 165--191.Tolle-KastenbeinR(2005)ArcheologiadellAcqua(WaterArchaeology).Milan:Longanesi.Vuorinen HS (2010) Water, toilets and public health in the Roman era. Water ScienceandTechnology: WaterSupply10(4)(inpress).Vuorinen HS, Juuti PS, and Katko TS (2007) History of water and health from ancientcivilizationsto moderntimes. Water Scienceand Technology:Water Supply 7(1):49--57.22 Water and Wastewater Management Technologies in the Ancient Greek and Roman Civilizations4.02 Membrane Filtration in Water and Wastewater TreatmentY Watanabe and K Kimura,HokkaidoUniversity,Sapporo,Japan& 2011Elsevier B.V. Allrights reserved.4.02.1 Membrane Application to Water Purication 234.02.1.1 CurrentStatus 234.02.1.2 MembraneFouling 234.02.1.2.1 Mainfoulant 244.02.1.2.2 Afnityofmainfoulant formembranes 304.02.1.3 MembraneFiltrationSystemsforControllingFouling 364.02.1.3.1 Channel occulationinmonolithceramicmembrane 364.02.1.3.2 Pre-coagulation/sedimentationinhollow-berUF/MFmembrane 404.02.1.3.3 HybridsubmergedMFmembranesystem 434.02.1.3.4 PVDFMembraneltrationwithpre-ozonation 454.02.2 Membrane Application to Wastewater Treatment 474.02.2.1 CurrentStatusofMBRs 474.02.2.2 MechanismofMembraneFouling 484.02.2.2.1 Effect ofmembranepermeateuxonfouling 494.02.2.2.2 Effect ofmembranematerial onfouling 544.02.2.2.3 Foulingpotential of carbohydrateassessedbylectinafnitychromatography 57References 604.02.1 Membrane Application to Water Purication4.02.1.1 Current StatusThe mainstay of water purication technology in the twentiethcenturywas sandltration, but sincethelate1980s, mem-braneltrationtechnologyusingRO/NF/UF/MFmembraneshasbeenappliedtothewaterandwastewatertreatment, de-salination, andwater reuse(RO, reverseosmosis; NF, nano-ltration;UF,ultraltration;MF,microltration).Figure1showsthehistorical development of membranetechnology in the water and wastewater treatment. Membraneltrationhas small foot print, extremely highsolidliquidseparationability, anditsmaintenanceis easy. Water puri-cationplants intheUnitedStates, theNetherlands, France,Australia, and Japan have introduced the membrane ltrationprocess.Figure2showstherecentincreaseintheamountofwater producedbythemembraneltration, whichincludeswaterpurication,desalination,andwastewatertreatment.35003000250020001000John F. Kennedy1950195519601965197519801985199019952000200519701500500If we could produce fresh water from salt water at a low cost that would indeed be a great serviceto humanity, and would dwarf any other scientific accomplishment 0Global accumulative amount of permeate (104 m3 d1)Water /wastewatertreatment(UF/MF)Brackish waterdesalination/wastewaterreuse (NF/ RO)Sea waterdesalination(RO)Cryptosporidium infection in Milwaukee (1993)Start of RO research in USA (1953)President J.F.Kenedy approved RO desalination as a national project (1961)Enhanced water works law in Japan (2001)Enhanced regulations of surface water in USA (1998)Figure 1 Development of membrane ltration. MF,microltration; NF,nanoltration;RO, reverese osmosis; UF,ultraltration.23Table 1 shows the large-scale water purication plantsusingmembraneltration. AllplantsinthetableusetheUFmembrane but a plant using monolith ceramic MF membranewiththecapacityof173000 m3d1isunderconstructioninJapan. Therehasbeenasignicant progressinthedevelop-mentofnewrobustMFmembraneswithnewpolymerssuchas PVDE and FTFE for water and wastewater treatment.Combiningrobust MFmembranes andthe other processessuch as coagulation, ozonation, biological/chemical oxi-dation, and powdered activated carbon adsorption andchemically enhancedphysical cleaning makes very efcientwater puricationsystem. Theyareveryeffectiveintheap-plicationtothelarge-scalewaterpuricationplant.The trend toward membrane ltration is expected to spreadworldwide during this century. However, there are severallimiting factors applying the UFmembrane andMFmem-brane to the water purication. Among them, fouling inmembrane is a major obstacle to widespread use of thistechnology.Theauthorshavebeenstudyingthemechanismandcon-trol of membrane fouling inwater treatment. This chaptersummarizes the authors research on membrane application tothewaterpurication.4.02.1.2 Membrane FoulingSeveral physical membrane cleaning methods such ashydraulic backwashing and air scrubbing have been developedand used routinely in many existing membrane plants tominimizemembranefouling. Despiteroutinephysicalmem-branecleaning, membraneltrationresistancegraduallyin-creases over a long period of operation, indicating thatmembranefoulingcannotbecompletelycontrolledbyphys-ical cleaning. Foulingthat cannot becontrolledbyphysicalcleaning is dened here as physically irreversible fouling.Controlofphysicallyirreversiblefoulingisimportantforthereductionof operationcost inamembraneprocessbecausethis type of fouling develops even when a very efcientphysical cleaningiscarriedout. Physicallyirreversiblemem-brane fouling canonly be canceled by chemical cleaning.However, chemical cleaning of the membrane should belimitedtoaminimumfrequencybecauserepeatedchemicalAmount of water (m3 d1)SWRONF+BWROLP+MF+UFIncrease by 25% each year32 000 000 m3 d1, 200635 000 00030 000 00025 000 00020 000 00015 000 00010 000 0005 000 000199019911992199319941995199619971998199920002001200220032004200520060Global amount of water produced by membrane processesFigure 2 Increase inpuried water bymembraneltration. BWRO, brackish water reverese osmosis; LP,low pressure; MF, microltration; NF,nanoltration;SWRO, seawaterreverese osmosis; UF,ultraltration.Table 1 Large-scalewater purication plants in world wideCountry Place (plant name) Capacity (103m3d1) Constructionyear Membrane WatersourceUSA Minneapolis(Fridley Plant) 360 2011 (to bebuilt) UF SurfaceCanada Mississanga, Ontario 302 2006 UF LakeSingapore Chestnut 273 2003 UF SurfaceUSA Minneapolis(Columbia Heights) 265 2005 UF SurfaceUSA Racine, Wisconsin 189 2005 UF SurfaceUSA Thornton,Colorado 187.5 2005 UF SurfaceCanada Kamloops,British Columbia 160 2005 UF SurfaceUK Clay Lane 160 2001 UF GroundGermany Roetgen/Aachen 144 2005 UF ReserviorUSA San Joaquin, California 136 2005 UF SurfaceSource: JapanWaterResearchCenter, HotNewsinwaterworks, No.56.24 Membrane Filtration in Water and Wastewater Treatmentcleaningmayshortenthemembranelifetimeanddisposalofspentchemicalreagentsposesanotherproblem.Membranefoulingstrongly dependsuponthestructureofmembrane (average size, size distribution, and density ofpores). Surface morphology and roughness are surely involvedinit.However,thischapterdescribestheeffectofonlynom-inalporesizeandmaterialsofmembraneonthemembranefouling.4.02.1.2.1 MainfoulantInanumber of previous studies onfoulingof membranesused for water treatment, natural organic matter (NOM),composed of a variety of nonbiodegradable organic com-pounds including humic substances, has been shown to be themajorconstituent causingmembranefouling. However, it isstill not clear which fraction of NOMcauses membranefouling.Inearlyworks,hydrophobicfractionsofNOM,suchas humic substances, wereconsideredtobethemajor fou-lants. Hydrophobic interactionandelectrostatic interactionweretheexplanationsforthebindingbetweenhydrophobicNOM and membranes. More recently, hydrophilic NOM withfeaturesofcarbohydrateorproteinhasbeenreportedbysev-eral researcherstobethemajorfoulant. AsexplanationsforthebindingbetweenhydrophilicNOMandmembranes,vander Waals attraction and hydrophobic interaction betweenmembranesandhydrophobicdomainsinhydrophilicNOMhave been suggested. In addition to NOM, metals and metalNOMcomplexes havebeenreportedas theconstituents af-fectingmembranefouling(Yamamuraetal.,2007a,2007b).Physically reversible fouling and physically irreversiblefouling have not been distinguished in many previous studies.Inaddition,manypreviousstudieswerebasedonshort-termexperiments,whicharenotsufcientforobservingphysicallyirreversiblefouling. As aresult, knowledgeof physicallyir-reversiblefoulingoccurringinmembraneltrationindrink-ingwatertreatment isverylimited; therefore, furtherstudiesneedtobecarriedout withspecial emphasis onphysicallyirreversiblefoulingfor moreefcient useof membranes. Inparticular, investigationof thecharacteristicsof componentsthat causephysicallyirreversiblefoulingwouldbeuseful fortheestablishmentofanewprotocoloffoulingcontrol.In this study, three MF/UF membranes that had beenfouled in long-termltration of surface water used as adrinkingwater source wereinvestigatedinterms of the re-coveryof water permeability bychemical cleaning andthecharacteristics of the foulant causing physically irreversiblefouling. Based on the results obtained from various analyses, ahypothesis regardingtheevolutionof physicallyirreversiblefoulingisproposed.Threedifferenthollow-bermembraneswereusedinthisstudy.Twoofthem wereMFmembranesandtheotherwasaUFmembrane. ThetwoMFmembraneshadthesamenom-inal poresizeof 0.1mmbut weremadefromdifferent poly-mers such as polyethylene (PE; Mitsubishi Rayon, Tokyo,Japan) and polyvinylidene uoride (PVDF; AsahikaseiChemicals, Tokyo, Japan). The UF membrane had a molecularweight cut-off of 100 000Da and was made frompoly-acrylonitrile (PAN; Toray Industries, Tokyo, Japan). Usingthese three different membranes, pilot-scale membraneltrationtestswerecarriedout inparallel usingtheChitoseRiversurfacewater.Thisriverowsthroughpeatareaanditssurfacewater containsmanyhumicsubstances. Theconcen-trationrangeof total ironandaluminumwas 0.71.7and0.05and0.7 mg l1. About 75%of themwere larger than0.45 mm. The PVDF and the PE membranes were submerged inseparate tanks andwereoperatedunder vacuum. The PANmembranewas housedinavessel andwas operatedunderpressure.Allmembraneswere operatedinthe outside-inowmode. The three membranes were operated with identical runcycles(ltration: 30 min; airscrubbing: 30s; hydraulicback-washing: 60 s)atthesameconstantuxof0.65 m3m2d1.Hydraulic backwashing was not accompanied by the additionof chlorine. Whenmembranefoulingbecamesignicant inthe submerged MF membranes despite the implementation ofperiodical backwashing, membranemodulesweretakenoutfrom the tanks and were cleaned by spraying pressurized wateronthemembranesurface.The average quality of the feed water and that of membranepermeatesareshowninTable2.Inthefeedwater,largepor-tions of aluminum(78%) andiron(75%) werepresent assuspended solids (40.45 mm), while manganese, calcium, andorganicmatterweremainlypresent indissolvedforms. Alu-minumand iron were effectively removed by the testedmembranesduetothestrictsolidliquidseparation. Ontheother hand, removal of manganese, calcium, and organicmatter was not signicant inany of the membranes. Thisimplies that thesizesof manganese, calcium, anddissolvedorganic carbon (DOC) were smaller than the pore sizes of thetestedmembranes.TheUFmembraneshowedslightlyhigherrates of removal of DOC and UV absorbance than those of thetwoMFmembranes, reectingthedifferencebetweenmem-braneporesizesoftheMF andUFmembranes.However,theconcentration of aluminumin the PAN membrane wasslightly higher than the concentrations in the MF membranes.Noreasonableexplanationforthisisavailableatpresent.Figure 3shows the changes intransmembrane pressure(TMP)inthethreemembranes.TheratesofincreaseinTMPinthethreemembranes wereconsiderablydifferent. As ex-pected, the tightest membrane (PAN) showed the highest rateof increase in TMP. The rates of increase in the two MFmembranesweredifferent despitethefact that theyhadthesamenominal poresize. This clearlyindicates that thema-terialsof themembranehaveasubstantial inuenceontheTable 2 Average rawwater quality during experimentTemperature(1C) 11.5pH 7.11Turbidity (NTU) 16.54UV absorbance at220 nm (cm1) 0.411UV absorbance at260 nm (cm1) 0.099TOC (mg 11) 2.43DOC(mg 11) 2.29THMFP (mg 11) 0.086Manganese (mg 11) 0.100Soluble manganese (mg 11) 0.074Ammonia Nitrogen (mg 11) 0.22DOC, dissolved organic matter; THMFP, trihalomethane formation potential; TOC, totalorganiccarbon.Membrane Filtration in Water and Wastewater Treatment 25evolutionofmembranefouling. Interestingly, theresultsob-tainedinthisstudyshowingthatthePEmembranewaslessfouled than the PVDF membrane are opposite to the results ofa previous study focusing on membrane fouling in membranebioreactors(MBRs)usedformunicipalwastewatertreatment.This implies that characteristics of foulants inthe case ofdrinking water treatment were different from those in the caseof wastewater treatment. Further investigationis neededtounderstand the inuence of membrane material on the rate offouling. Inallofthetestedmembranes,increaseinTMPwasnot constant andrapidincreases inTMPwereseenseveraltimes.AftertherapidincreasesinTMP,however,thevalueofTMPgraduallydeclineddue tothe periodical backwashingexcept for the case of the PVDF membrane. On days 31 and 41,an additional physical cleaning (spraying pressurized water onthemembranesurface)wasneededtomaintainthepermea-bility of the PVDF membrane. This additional physicalcleaning worked well and substantial reduction in TMP in thePVDFmembranewasseenaftercleaning. Chemical cleaningwasnot carriedout at that time. Basedontheobservationsmentionedabove, it is assumedthat the rapidincreases inTMPshowninFigure3werecausedbytheaccumulationofcake on the surfaces of the membranes. The three dashed linesshown in the gure are assumed to represent the evolution ofphysicallyirreversiblefoulinginthethreemembranes,whichaccumulatedandremaineddespiteoftheimplementationofperiodical backwashingandadditional physical cleaning. AsseeninFigure 3, the rates of occurrence of physically ir-reversiblefoulinginthethreemembranesweredifferent.Toinvestigate the features of constituents that were re-sponsiblefor physicallyirreversiblefouling,the foulantsweredesorbedfromthefouledmembranesat theterminationofthe operationand thentheir chemical characteristics wereanalyzed.Whenthepilotoperationswereterminated,fouledmembranes were taken out fromthe ltration units. Themembraneberswere