Historical Note/

The Wells of Pompeiiby Wayne F. Lorenz and Edward J. Wolfram

IntroductionIt is well known that many of the ancient Roman

cities obtained domestic water from aqueducts thatbrought fresh spring water from nearby mountain sources.The many aqueduct archeological sites in Europe, partsof Africa and the Middle East stand as impressive monu-ments to public water projects. Indeed, the water providedby the aqueducts was a major factor in the economic andsociological development of the Roman Empire. How-ever, the Romans also relied on other water sources toprovide for potable water needs, including groundwater.

The legendary city of Pompeii was served by a greataqueduct system called the Serino (or Aqua Augusta)Aqueduct. Built primarily for providing quality water toNaples and the Roman navy that harbored in a sectionof what today is the Bay of Naples; the aqueduct alsoprovided water to several other Roman cities in the bayarea, including Pompeii.

Pompeii became a Roman colony under GeneralLucius Cornelius Sulla in about 80 BC. The Serino Aque-duct was constructed during the Augustus period, prob-ably between 33 and 12 BC. Until the construction of theSerino Aqueduct, Pompeii relied on other water sources.

In addition, it is likely that the aqueduct was occa-sionally out of operation during the Roman occupationof Pompeii. A great earthquake occurred in AD 62 anddestroyed some of the aqueduct. The aqueduct repair tookmany years and the repairs were not complete when MtVesuvius buried Pompeii in AD 79.

Rain water harvesting was practiced in householdsthroughout the city. Structures were built with what arecalled compluviums, or gutters and rectangular openingsin the roof, that allowed rain water to collect and dropdown to cisterns, called impluviums, that were used aswater storage vessels, see Figure 1. This cistern watersupply was only as reliable as the weather patterns wouldallow. In modern times, the Pompeii area receives about840 mm (33 inches) per year of precipitation.

Wright Water Engineers, Inc. and Wright PaleohydrologicalInstitute, 2490 W. 26th Ave., Ste 100A, Denver, CO 80211;(303) 480-1700; fax: (303) 480-1020; wlorenz@wrightwater.com;edwardjwolfram@gmail.com.

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Figure 1. Compluviums, roof openings such as shown herein the roof of a Pompeii villa, the Casa dei quattro stili(house of the four styles), allowed rainwater collection inimpluviums below.

Groundwater was another source of water to Pompeii.A remarkable aspect of Pompeii is that there have been 22groundwater wells identified in the excavated portion ofthe city. About one third of the area of Pompeii remains tobe excavated, so there were probably more wells servingthe city’s population in the first century AD.

Because the aqueduct supplies were sometimes notavailable and rain water was dependent on the weather,groundwater was the most reliable of all the watersupplies to Pompeii. However, its quality for drinkingpurposes was not as good as the rain water or thespring-fed aqueduct supply. Many of the wells were inprivate homes, but there were several larger wells that

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Figure 2. Location of wells within Pompeii.

were strategically situated for public access and publicbathing. The locations of the known wells in Pompeii areshown in Figure 2, including the public access RegionVI Well and the Stabian Bath Well.

The unique preservation of Pompeii shows theprevalent use of wells in the city. Groundwater was avery important water supply source to Pompeii and otherRoman cities. The aqueducts were vital; however, thewells were more reliable.

When the Romans first occupied Pompeii in about80 BC, groundwater was the main water supply. However,the Serino River was located nearer to the city than itspresent location and would have also served as a basicwater supply to Pompeii. The Serino River was partiallyfed by prolific fresh water springs.

The digging of wells for water supply is an ancientengineering practice that was performed in ancient timesmuch as it is performed in modern times. Today, hydro-geologists use sophisticated engineering approaches andcomputerized drilling equipment to locate and developgroundwater for domestic use. However, the engineeringprinciples of developing groundwater as a water supplyremain unchanged—to extract groundwater, one mustgo to it and provide a method for lifting and movingthe water to the point of use on the surface. This is whatthe Romans did.

Roman wells were constructed by lowering laborersinto the well shaft and using hand tools for excavation.This was typical construction throughout the RomanEmpire. Thomas and Wilson (1994) reported on Romanwells constructed on farms in the area to the west andsouth of Rome. The shapes of the well shafts varied butall were large enough for a man to be lowered into themfor excavation. The majority of Roman wells were less

than 30 m (100 feet) deep as beyond this the lifting ofwater becomes a very arduous task. Some of the wells inPompeii were 30 m deep and some were deeper.

Most known Roman wells are similar to modern dugwells; however, some wells were over-excavated and thenthe sidewalls were filled with gravel held in place bystones. Roman-dug wells in England have lime stonesthat are from 5 to 8 cm (2 to 3 inches) in thickness withthe stones shaped to conform to the wells’ circumference,thereby giving stability and finish to the masonry. Aprofile figure of a Roman well discovered in Biddenham,England, in 1857 is shown in Figure 3 (Thompson 1867).

Pompeii WellsThere is groundwater within the volcanic strata

beneath Pompeii. The depth to groundwater is between 20and 37 m, with the shallower depth occurring on the southside and the deeper groundwater located on the north side(Eschebach 1994). The wells in Pompeii were typicallyexcavated with shaft dimensions greater than 1 m becauseof the well depth needed. Several of the larger wells hadrectangular shafts with side dimensions of 2 to 3 m.

The volcanic nature of the geology underneathPompeii would lead one to conclude that the groundwaterquality would be less than desirable for domestic usepurposes. In a study of groundwater in a volcanic aquiferin Guatemala, Mulligan (2006) reported on high sulfateand chloride concentrations in well water from solubleash layers. In Pompeii, Eschebach (1994) states that thegroundwater had a sulfurous smell and was barely fit fordrinking.

The volcanic geology was likely a factor regardingconstruction of wells in Pompeii. As the wells had to

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Figure 3. Roman well profile from Biddenham, England(Thompson 1867).

be hand dug, a limiting factor to the depth of the wellcould have been the availability of air for the workmen ascarbon dioxide, hydrogen sulfide and methane all occurin volcanic rocks. Even the Roman author Vitruvius gaveprecautions against asphyxiation regarding gases in wells(Vitruvius 1914). Whether or not the Pompeii groundwatersupply was used extensively for potable purposes has notbeen fully established.

Three wells that were used for public purposes inPompeii were investigated—the Region VI Well, StabianBath Well, and the well at the Doric Temple.

Region VI WellA large well structure with interior dimensions of 2 m

by 2.3 m is located behind a public fountain in Pompeiiat the approach of Region VI, from the direction of thePompeii Forum. This location was at the confluence ofthree major thoroughfares in the northwest portion ofPompeii. It was easily accessed by Pompeian citizensand the major function of this well appears to havebeen for public potable use. This may also be one ofthe older wells in the city, as it is located in an area

Figure 4. Well and adjacent water fountain at Pompeii.

the Etruscans had developed and inhabited prior to theRoman occupation of Pompeii.

There are several unique aspects of this well. First, itappears there are the remains of a water tower adjacent toit. Only the base section of the tower remains on the eastside of the well shaft. The water tower may have receivedwater from both the well and, later, the aqueduct system.Water was served from the water tower through leadpipelines that ran along a pipe chase that was constructedinto the sides of the water tower.

The other unique aspect of this well is that a publicwater fountain was located just 3.1 m (10.5 feet) fromthe well. The water fountain was supplied from thewater tower and provided water to nearby residents. Aphotograph of the well structure and the water fountain isshown in Figure 4.

There exists a structure that covers the well shaft.The structure consists of mortar, brick and rock. As seenin Figure 4, the structure appears to have been restoredseveral times and in different manners with respect tothe types and placement of brick/rock. The roof of thestructure has been built in a semi-circular, arch shape.

Stabian Bath WellA larger well (2.90 m by 2.0 m by ∼25 m deep) was

used as a water supply to serve the Stabian Baths, oneof the larger baths in Pompeii (Oleson 1994). This welldates back to the second century BC (Maiuri 1931). Thewell shaft was extended from the ground surface to thesecond story of the bath complex to make it convenientto fill a reservoir, see Figure 5. Water would then flow,when needed, from this reservoir by gravity for use inthe bath pools.

The well shaft was constructed using mortar andstones (in a style called opus incertum); and there appearsto be a layer of hydraulic cement that was used to coverthe interior well shaft walls. There is a buildup of calciumcarbonate scaling on the sides of the well shaft walls,especially in the areas where the water was lifted fromthe well using buckets on a wheel and delivered to thereservoir. This scaling is characteristic of a water qualitythat has high calcium hardness (Figure 6).

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Figure 5. Stabian bath well and shaft extending to secondstory.

Figure 6. Stabian well shaft extending into the ground.

For this Stabian well, a water lifting mechanism wasused to lift the water from the well into the bath complex.There are scraping marks on the wall and the presence ofthe calcium carbonate scaling, indicating the nature andlocation of the lifting mechanism.

Wells were also used for water supply for the Forumand Republican baths in Pompeii.

Doric Temple WellOne of the earliest wells constructed in Pompeii is

located south of the Doric Temple. The well probablydates from the sixth century BC, since the temple wasconstructed during the period of 555 to 500 BC. The wellstill exists and has a tholos (or circular, pillared structure)over the well that was added in the third or second centuryBC (Crouch 1993). The wellhead consists of a puteal (acylindrical, decorated hollow stone to protect the well)that is about 0.77 m (2.5 feet) high and has an internaldiameter of 0.67 m (2.2 feet) (Figure 7).

The City of Pompeii gives us a snapshot of ancientRoman life and culture. The availability of, and methodsof delivering, water to the points of use was preservedwhen Mt Vesuvius erupted and buried the city in ash

Figure 7. Doric temple well.

and pumice. This record shows us that Romans relied onmultiple water sources, including groundwater suppliedby wells.

ReferencesThompson, F. 1867. Roman well at Biddenham, 1858. In

Notes of the Bedfordshire Architectural and ArchaeologicalSociety , Vol. 1 no. 08. Bedfordshire, UK: T. Laurence.

Crouch, D. 1993. Water Management in Ancient Greek Cities .New York: Oxford UP.

Eschebach, L. 1994. Wasserwirtschaft in Pompeii. In CuraAquarum in Campania , Proceedings of the 9th Interna-tional Congress on the History of Water Management andHydraulic Engineering in the Mediterranean Region , Octo-ber 1–8, ed. N. de Haan and G.C.M. Jansen, 67–78.

Oleson, J.P. 1994. Water-lifting devices at Herculaneum andPompeii in the context of Roman technology. In CuraAquarum in Campania , Proceedings of the 9th Interna-tional Congress on the History of Water Management andHydraulic Engineering in the Mediterranean Region , Octo-ber 1–8, ed. N. de Haan and G.C.M. Jansen, 1–12.

Maiuri, A. 1931. Notizie Delgli Scavi D’Antichita , Ser. 6, vol.1–15, 566–569.

Mulligan, B. 2006. Geochemical Evolution and GroundwaterFlow in a Volcanic Aquifer . Calgary, Alberta, Canada:University of Calgary.

Thomas, R., and A. Wilson. 1994. Water supply for Roman farmsin Latium in South Etruria. Papers of the British School atRome 62: 139–196.

Vitruvius. 1914. The Ten Books on Architecture. Translatedby M.H. Morgan. Cambridge: Harvard University Press.8.6.12–13. www.gutenberg.org.

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