Appendix C Glossary of Terms and Acronyms

AC - Asbestos cement; type of sewer pipe commonly used for pressure force mains up to the 1970s.

Alternatives - Within a Strategy, specific infrastructure investments or operational changes for achieving objectives.

Asset Management - A process for maintaining a desired level of customer service at the lowest life cycle cost.

CDC - Capacity Development Charge; a LOTT fee defined in OMC 133.08.210.

CI - Cast iron; pipe formerly used in situations where there were soil loading or other concerns; typically lined with cement or other material to inhibit corrosion of the metal.

Condition Assessment - A core component of an Asset Management Program, it is "the collection of data and information through the direct inspection, observation, and investigation an indirect monitoring and reporting, and the analysis of the data and information to make a determination of the structural, operational and performance status of capital infrastructure assets." (EPA Report No. EPA-ORD-NRMRL-CI-08-03-02)

Criteria - Measures or considerations used to evaluate criteria, e.g. when ranking lift stations in a Vulnerability Assessment.

DI - Ductile iron; similar to CI pipe and used in applications where CI would have been used in the past; for sewer it is lined with polyethylene or other material that resists corrosion from wastewater (cement no longer used).

EDDS - City of Olympia’s most recent Engineering Design and Development Standards.

ERU - Equivalent Residential Unit; defined in OMC 13.08.190 and used to convert non-residential water use to an equivalent residential use for the purposes of estimating wastewater flows and establishing monthly rates.

GFC - General Facility Charge; a City of Olympia Wastewater Utility fee defined in OMC 13.08.205.

Goals - Broad, qualitative statement of what the Wastewater Utility hopes to achieve.

GPD - Gallons per day; Gallons per minute = GPM.

HDPE - High density polyethylene; becoming more commonly used as a sewer force main pipe, it can also be used in gravity flow situations.

I&I - Infiltration and Inflow; infiltration is groundwater that leaks into pipes through joints, cracks and breaks in pipes, manholes and other wastewater appurtenances, while inflow is groundwater and/or stormwater that is piped into the sewer system (intentionally or otherwise) via catch basins, roof leaders, basement drains, areas drains and other directly piped sources of stormwater, as well as stormwater flowing through unsealed manhole covers.

LOTT - Lacey, Olympia, Tumwater and Thurston County, also referred to as the LOTT Clean Water Alliance (, or LOTT Partners.

MGD - Million gallons per day.

Objectives - Specific, measurable statements of what will be done to achieve these Goals within a particular time frame.

OMC - Olympia Municipal Code; Chapter 13.08 of the OMC addresses wastewater service, 13.20 wastewater pretreatment requirements, and 4.24.010B monthly rates and connection fees.

OSS - Onsite Sewage System; also called a septic system.

PPM - Parts per million; 1 ppm is equivalent to 1 milligram per liter (mg/L) of water.

PSI - Pounds per square inch; a measurement of pressure equal to about 2.3 feet of head.

PVC - Polyvinyl chloride; the most prevalent type of gravity sewer pipe currently in use. Pressure class PVC is also used for sewer force mains.

RCW - Revised Code of Washington; the statutes of the State of Washington

Sewer Service Area - Area within which the City of Olympia provides or intends to provide sewer service. Generally, this area includes almost the entire City and its UGA, but there are some exceptions - see Appendix M for a map of the City’s Sewer Service Area.

Side Sewer - That portion of the sewer beginning 2 feet outside the outer foundation wall of the structure, to and including the connection to the public sewer main or STEP tank, as applicable. This includes pressurized (grinder pump) side sewers. The terms "sewer service line", "sewer lateral", "sewer service connection", and "individual pressure sewer connection" are interchangeable with the term "side sewer". Property owners whose building(s) are connected to the public sewer main own, and are responsible for maintaining, their side sewer.

SFR - Single family residence; considered 1 ERU (see above) for the purposes of connection fees and monthly rates, as opposed to a residential structure with more than two units, where each unit is considered 0.7 ERU.

STEP System - Septic Tank Effluent Pumping system; a method of collecting wastewater from a residence or building in a septic tank and pumping the effluent into a STEP pressure main that discharges into the City’s gravity sewer collection system.

Strategies - General approaches or methods for achieving Objectives and resolving specific issues. Strategies speak to the question "How will we go about accomplishing our Objectives?"

TRPC - Thurston Regional Planning Council.

UGA - Urban Growth Area; established as part of the implementation of the Growth Management Act. Municipal wastewater utilities, with some exceptions described in the relevant RCW, can only serve customers within their City limits and UGA.

VC - Vitrified clay; a type of gravity sewer pipe commonly used until the 1970s.

WAC - Washington Administrative Code; the regulations that implement the RCW through the state’s executive branch agencies.