Natural History. A member of the weasel family, the sea otter is the smallest marine mammal in North America. The southern, or California, sea otter ranges along the coast from San Mateo County southward through Monterey County and down to Santa Barbara County.Unlike other marine mammals, sea otters don't have a thick layer of blubber. member of the weasel family, the sea otter is the smallest marine mammal in North America. The southern, or California, sea otter ranges along the coast from San Mateo County southward through Monterey County and down to Santa Barbara County. Unlike other marine mammals, sea otters don't have a thick layer of blubber.
In modern plumbing, a drain-waste-vent (or DWV) is part of a system that removes sewage and greywater from a building, and regulates air pressure in the waste-system pipes to aid free flow.t the building drain system's lowest point, the drain-waste vent is attached, and rises (usually inside a wall) to and out of the roof. Waste exits from the building through the building's main drain and flows through a sewage line, which leads to a septic system or a public sewer.
Drain-Waste-Vent Plumbing Systems. Understand how your homeâs drain-waste-vent plumbing systems work with this expert illustrated explanation. The system of pipes that carries water and waste to a sewer line or septic tank is call the drain-waste-vent (DWV) system. As the name implies, it has three components: Drain lines collect water from sinks, showers, and tubs; waste lines carry waste from toilets; and vent lines exhaust sewer gases and allow wastes to flow freely.