Homeowner Reference
Plumbing Glossary
Plain-English plumbing definitions for drains, sewers, water heaters, fixtures, and water quality, written for Santa Cruz County homeowners.
Plumbing jobs move faster when everyone shares the same vocabulary. This glossary explains the terms Wade's crews use on residential and commercial calls across Santa Cruz County and nearby foothill communities.
Use it before a repair visit, while reading an estimate, or when you want to understand why a drain, water heater, or sewer recommendation matters for an older coastal or hillside home.
Looking for the other glossary? Browse the Septic Glossary.
A
- ABS PipeBlack plastic drain pipe used in many older drain, waste, and vent systems. Common in Santa Cruz County homes built before widespread PVC adoption.
- Anode RodA metal rod inside a tank water heater that corrodes first to protect the tank from rust. Replacing it extends heater life in hard coastal water.
B
- Backflow PreventerA valve assembly that stops contaminated water from flowing backward into the clean drinking water supply during pressure drops or cross-connections.
- Ball ValveA quarter-turn shutoff valve with a rotating ball inside. Reliable for main water shutoffs and fixture supply lines in homes and businesses.
- BlackwaterWastewater from toilets and kitchen sinks that may contain pathogens and grease. It must stay separate from clean water and greywater systems.
C
- Check ValveA one-way valve that lets water flow forward but closes to prevent backflow. Used on sump pumps, recirculation loops, and some supply lines.
- CleanoutA capped access fitting on a drain or sewer line that lets plumbers snake, jet, or camera the pipe without cutting into walls, floors, or landscaping.
- Copper PipeDurable metal supply pipe common in California homes for decades. Handles hot and cold potable water when properly soldered, brazed, or press-fit.
- Cross-ConnectionAny plumbing link where non-potable water could enter the drinking supply. Backflow preventers, air gaps, and vacuum breakers eliminate these hazards.
D
- Drain SnakeA flexible cable spun into a drain to break up clogs from hair, grease, or roots. First-line tool before hydro jetting or camera inspection.
- DWV SystemThe drain, waste, and vent piping that carries wastewater out of a building while balancing air pressure so traps stay sealed and fixtures drain well.
E
F
- Faucet AeratorA screened fitting on a faucet spout that mixes air into the stream to reduce splash, save water, and keep steady pressure at kitchen and bath sinks.
- Fixture Shutoff ValveThe small valve under a sink or behind a toilet that shuts off water to one fixture without turning off the whole house, building, or irrigation line.
- Floor DrainA drain set flush with the floor to catch water from washers, water heaters, or garage runoff. Must connect to the proper sanitary or storm system.
G
- Garbage DisposalA motorized grinder mounted under a kitchen sink that shreds food waste before it enters the drain. Requires adequate water flow and proper use.
- Gas LinePiping that delivers natural gas or propane to water heaters, ranges, dryers, and fireplaces. Suspected leaks require immediate professional repair.
- Gate ValveA multi-turn shutoff that raises an internal gate to open flow. Common on older water mains but can seize, leak, or break if left unused for years.
- Grease TrapA tank that captures fats, oils, and grease from commercial kitchen drains before they clog sewer lines, back up floor drains, or trigger code violations.
- GreywaterWastewater from showers, tubs, lavatories, and laundry that excludes toilet waste. May be reused for landscape irrigation where local code allows.
H
- Hard WaterWater with high dissolved calcium and magnesium that leaves scale on fixtures, showerheads, and heating elements while shortening appliance life.
- Hose BibAn exterior water spigot for hoses and irrigation. Should include a vacuum breaker wherever backflow into the potable supply is a concern on the property.
- Hydro JettingHigh-pressure water cleaning that scours grease and roots from pipe walls. More thorough than snaking alone for recurring drain and main sewer clogs.
L
M
- Main Sewer LineThe buried pipe that carries all building wastewater from the cleanout to the municipal sewer main, private septic tank, or approved disposal point.
- Mixing ValveA valve that blends hot and cold water to a set temperature. Protects against scalding at showers, tub spouts, and commercial fixture banks.
P
- P-TrapA U-shaped pipe under sinks and tubs that holds water to block sewer gas. The standard trap shape used on most modern residential and commercial fixtures.
- PEX PipeFlexible plastic supply tubing joined by crimp or expansion fittings. Popular for repipes and long runs with fewer joints than rigid copper pipe.
- Pipe BurstingA trenchless method that pulls a new pipe through an old sewer line while fracturing the existing pipe outward. Limits yard damage on long laterals.
- Pipe LiningA trenchless repair that inserts a resin-coated liner into an existing pipe, then cures it to form a new smooth interior without full excavation.
- Plumbing TrapA curved pipe section that retains water to seal out sewer gases. Every fixture with a drain requires an approved trap under local plumbing code.
- Potable WaterWater safe for drinking, cooking, and bathing. Supply lines and fixtures carrying potable water must meet health codes and backflow protection rules.
- PRVA valve that lowers street water pressure to a safe level for pipes, fixtures, and water heaters. Protects against leaks and appliance damage.
- PVC PipeWhite or gray plastic pipe used for drain, waste, vent, and some cold-water applications. Lightweight and corrosion resistant in drainage systems.
R
S
- Sewer Camera InspectionA waterproof camera pushed through drains or sewers to record pipe condition, roots, bellies, and cracks before repair, jetting, or a home sale.
- Sewer LineAny pipe carrying wastewater to treatment, including interior building drains and the underground lateral that reaches the street main or septic tank.
- Shower ValveThe in-wall valve that mixes hot and cold water and controls flow to the shower head and tub spout. Cartridge or valve body leaks often hide inside the wall.
- Smoke TestA diagnostic test that blows non-toxic smoke into drain and vent systems to reveal illegal connections, open pipes, or hidden leaks in walls.
- Storm DrainPiping and grates that carry rainwater and surface runoff to creeks or storm systems. Must stay separate from sanitary sewer and potable lines.
- Sump PumpA pump in a pit that removes groundwater before it floods crawl spaces or basements. Needs reliable power, discharge piping, and a check valve.
- Supply LinePiping that delivers pressurized potable water from the main to fixtures, water heaters, hose bibs, and appliances throughout the home or business.
T
- T&P Relief ValveA safety valve on tank water heaters that opens if temperature or pressure exceeds safe limits. Discharge pipe must route to a visible floor drain or exterior.
- Tankless Water HeaterA unit that heats water as it flows, without a storage tank. Needs adequate gas or electrical service, venting, and sizing for peak fixture demand.
- Toilet FlapperThe rubber seal in the tank that lifts to flush and closes to stop fill. A worn flapper causes silent running, phantom fills, and high water bills.
- Trenchless Sewer RepairMethods to fix or replace buried sewer pipe with minimal digging, including cured-in-place pipe lining and pipe bursting instead of open trenching.
V
W
- Water Filtration SystemFilters or treatment units that reduce sediment, chlorine, taste issues, or specific contaminants in drinking, cooking, and bathing water at the tap.
- Water HeaterEquipment that heats domestic hot water in a storage tank or on demand. Gas, electric, and heat-pump types serve Santa Cruz homes of every size.
- Water LineAny pipe carrying potable or irrigation water, from the utility main connection at the street to individual fixture supplies inside the building.
- Water MainThe primary pressurized pipe bringing water into a property, often with a meter and main shutoff before interior supply branches split off indoors.
- Water SoftenerA treatment unit that removes hardness minerals to reduce scale on fixtures and extend water heater life. Requires salt or potassium and periodic service.
Wade's Plumbing & Septic
Need this explained for your home?
If a term on this page matches something failing at your property, call and we will help you sort out the next practical step.
Mon to Fri 9:00am to 5:00pmsupport@wadesinc.io