Sewer

Sewers, also known as sewer systems, were underground pipe or tunnel systems built beneath cities for the purpose of transporting away wastewater or "sewage" to somewhere else for disposal or treatment. These were essential to most large civilized settlements, as not disposing of wastewater could create a breeding ground for diseases.

Construction
Sewers were often dug and constructed as cities were planned and built. In the case of rather older cities, sewers may have been excavated after their street layouts were already in place.

Some cities sported sewers that were, in part, the repurposed structures of older cities they were built atop of. Such examples of this included the former city of Sarbreen beneath Ravens Bluff and the former deep gnome city that Calimport stood atop of.

The simplest form of sewer system consisted of various drains and grates&mdash;located in streets, alleyways, and some homes&mdash;that emptied directly into an underground river or cistern. The next step up from that were sewers consisting of stone halls, large enough to allow for maintenance, featuring clay or metal pipes. These could become rather mazelike and confusing to navigate.

Functionality
Cities that stood close to rivers or tidal bodies of water often chose to design their sewers to operate on a tidal flushing system. This meant they utilized their nearby source of moving water that can be diverted to flush local wastes away to elsewhere. This was often the cheapest & easiest route for such cities to take, but it could cause problems for those downstream from them.

In order to prevent severe clogs, many sewer systems installed screens across their channels to "catch" large debris, which would then be cleared and have their debris taken to the surface by city workers. Sometimes these screens had spikes jutting out, which served to both catch more debris and dissuade those illicitly traversing sewers from getting up close to the screens and tampering with them, such as with things like acid or files.

When such screens were installed throughout much of a sewer, they had the effect&mdash;from the point of view of those who regularly traversed sewers of dividing it into segments. With city crews working on particular segments and criminals finding them to be frustrating barriers to what would otherwise be an ideal covert highway.

Residential Aspect
In most cities in the Realms, buildings had indoor rooms known as garderobes (or less formally as "jakes"). These consisted of a seat, a gravity drop pipe descending beneath it, a wiping cloth to be washed for later use, and large jugs of water with which to wash and flush down waste. Waste would then be carried down the pipe to a wastewater cistern with a turn-the-balun connection to the sewers beneath. On average privies were constructed in this manner instead of directly connecting to sewers, but in certain cities a direct connection was oftentimes the case.

Hazards
Sewers often had a strong stench within them, making it difficult for many creatures to smell much of anything. Potentially even causing nausea.

In areas where there was poor ventilation, pockets of methane gas were likely to form from the waste in sewers.

Prevalence of Sewers in the Realms
All of the cities on the continent of Faerûn that were noted as having sewers were as follows:
 * Archenbridge, Athkatla, Berdusk, Bezantur, Calaunt, Dagger Falls, Daggerford, Elturel, Elversult, Helm's Hold, Hlondeth, Luskan, Memnon, Mulmaster, Neverwinter, Nonthal, Oparl, Phlan, Ravens Bluff, Riatavin, Saradush, Saelmur, Saerloon, Scornubel, Selgaunt, Schamedar, Silverymoon's Northbank district, Soorenar, Suzail, Tantras, Thentia, Tilverton, Urmlaspyr, Westgate, Zhentil Keep.

And though not a city, the fortress of Candlekeep also had a sewer. In the land of Zakhara, the city of Huzuz was known to have a sewer.

Some drow communities in the Underdark were known to have sewers, but these were never large or extensive and their waste always flowed directly to fungus beds, which in turn fed upon the sewage.

Most Notable Sewers

 * Sewers of Baldur's Gate
 * Sewers of Calimport
 * Sewers of Neverwinter and its subsection, the Blacklake Sewers
 * Sewers of Ravens Bluff
 * Sewers of Waterdeep
 * Underscar, the sewer system of Helm's Hold

History
Over the course of Toril's history, sewer systems were developed for various settlements by dwarves, halflings, and in rarer cases enterprising humans and elves. But over the course of centuries it was rock gnomes, more than any other race, who became specialized in designing, repairing, and perfecting the sewer systems of large mixed-population cities. Though the average human citizen was likely unaware of the gnomish oversight involved in their sewers. The existence of sewers on Toril dated as far back as the city of Memnonnar, which was established by the Great Pasha Memnon in approximately.
 * General History
 * Specific History

Centuries later, sewers were constructed by the elven kingdom of Earlann, within such cities as Ascalhorn and Myth Glaurach, followed by the Netherese Empire.

In the millennia since Memnonnar was founded, sewers continued to be constructed for cities within the Lands of Intrigue, often repurposing the ruined cities of High Shanatar. In the years leading up to the Eye Tyrant Wars, beholders established cults within many of these sewers, planning to one day have their forces pour out and conquer the cities when they had grown strong enough.

During the time of the Shoon Imperium, most of the cities in the Lands of Intrigue that were under its rule possessed sewers, including its capital Shoonach. When Strohm I led an assault on the city in the, he had many of his forces enter Shoonach through its sewers.

Inhabitants
Much of the wildlife in city's were relagated to sewers, wherein they were likely to become exposed to disease. The creatures that were most often found to be lairing within sewers on Toril included chuuls, meazels, giant crocodiles, various varieties of oozes, cesspit oozes, yuan-ti, and the extaminaars. But most of all rats and giant rats. The sewers of Zhentil Keep even had their own unique strain of rat.

In addition to animals and monsters, the moist, dark environment of sewers made them an excellent space for fungi to grow.

When it came to the humanoids that inhabited cities, the destitute and criminal elements of society were likely to hide in the sewers, hide the bodies of their victims, or make a home for themselves. Criminal elements such as outlaws, smugglers, thieves, and outcasts often hid within sewers of the cities. In some cases even building their own societies. Sewers were also popular hiding spots for cults to outlawed deities.

Organizations

 * Sometimes city officials hired adventurers, mage guils, or wizards-for-hire to deal clear out or deal with monsters in their sewers.
 * The three largest rock gnome clans known for their expertise in sewers were the Barbellows, the Narlens, and the Thallows.
 * In the Vilhon Reach, clerics of the Church of Silvanus provided magical support free of charge to the cities in which they reside, keeping the waters clean and the sewers as free of disease as possible.
 * In urban areas, the Church of Malar sometimes held holy hunts within sewers.
 * Many clerics of the Church of Shaundakul sold accurate-as-possible maps of short underground routes, such as sewer systems.
 * The watchmen of any city were likely to patrol their sewers, but rarely for any extended period of time. One such example was the City Watch, and later the City Guard, of Waterdeep.

Trivia
Mayors often owned maps of their city's sewers.

Appearances

 * Video Games
 * Baldur's Gate series (Baldur's Gate • Baldur's Gate II: Shadows of Amn) • Neverwinter Nights series (Neverwinter Nights: Darkness over Daggerford) •