Electric, Water, Gas and Sewer Services Industry Terminology

Activated Sludge

A biological wastewater treatment process where aerated basins support microbial communities that consume organic matter, followed by settling to separate biomass from treated effluent.

The plant converted from trickling filters to activated sludge to meet tighter BOD limits; High F/M ratio caused filamentous bulking in the activated sludge process; We increased aeration to boost dissolved oxygen for nitrification in activated sludge.

Advanced Metering Infrastructure (AMI)

A system of smart meters, two-way communications, and data management that enables interval reads, remote connect/disconnect, outage detection, and voltage monitoring.

The AMI rollout cut meter-reading truck rolls by 40%; Using AMI interval data, we designed a new TOU rate; Last-gasp AMI pings helped pinpoint the outage location.

Asset Management

A structured lifecycle approach (often aligned to ISO 55000) to plan, operate, maintain, and replace utility assets based on risk, condition, and cost.

Our asset management plan prioritizes mains by failure probability and consequence; Condition-based maintenance extended pump life; We used risk scoring to schedule substation transformer replacements.

Backflow Prevention

Devices and practices that prevent reverse flow from customer premises into potable water systems, protecting against contamination.

RPZ backflow preventers are tested annually at high-risk sites; Cross-connection surveys identified facilities needing backflow devices; A backflow event triggered a boil-water advisory.

Baseload

The minimum level of electricity demand on a system over a given period, and traditionally the generation that runs continuously to meet it.

The coal unit was retired as baseload shifted to combined-cycle gas and nuclear; Demand growth and DERs flattened baseload needs; Our IRP shows declining baseload due to efficiency gains.

Biochemical Oxygen Demand (BOD)

A measure (mg/L) of biodegradable organic material in water, indicating how much oxygen microorganisms will consume.

Influent BOD averaged 250 mg/L and effluent 15 mg/L; We sized aeration based on peak BOD loading; High BOD from an industrial user triggered surcharge fees.

Capacity Factor

The ratio of a power plant’s actual energy output over a period to its maximum possible output if it operated at full nameplate power continuously.

The wind farm’s capacity factor was 42% last year; Upgrades improved the hydro unit’s capacity factor; Solar capacity factors peak in summer but drop with cloud cover.

Capital Expenditure (CapEx)

Long-term investments in assets such as pipes, substations, plants, and meters that are capitalized and typically added to rate base.

The AMI deployment is treated as CapEx; We rebalanced from OpEx to CapEx via capitalized cloud implementation costs; CapEx timing affects rate base growth and depreciation expense.

Cathodic Protection

Corrosion control for buried or submerged metal assets (e.g., gas pipelines, tanks) using sacrificial anodes or impressed current systems.

Annual CP surveys confirmed adequate pipe-to-soil potentials; We installed an impressed current system on the steel main; Coating holidays were detected and mitigated via CP adjustments.

Combined Sewer Overflow (CSO)

Discharge events where combined stormwater and wastewater systems overflow to receiving waters during wet weather.

The consent decree requires CSO reductions via storage tunnels; Real-time control cut CSO frequency by 30%; Green infrastructure mitigated CSO volumes in the downtown basin.

Cost of Service Regulation

A ratemaking framework where utilities recover prudent operating costs plus depreciation and an allowed return on rate base.

The utility filed a test-year cost of service study; A tracker was approved to true up fuel costs; Staff recommended adjustments to the revenue requirement under cost-of-service.

Cross-Connection Control (CCC)

Programs, ordinances, and device testing to prevent cross-connections that could allow contaminants to enter the potable water system.

The CCC ordinance mandates annual RPZ testing; Surveys found unprotected irrigation cross-connections; CCC compliance is audited during sanitary surveys.

Decoupling

A regulatory mechanism that breaks the link between utility revenues and volumetric sales, stabilizing revenue and supporting efficiency and DER adoption.

Annual revenue decoupling adjustments true up weather-driven sales swings; Decoupling reduced earnings volatility; The commission approved decoupling alongside PBR metrics.

Demand Charge

A tariff component billed on a customer’s peak kW over a period, reflecting capacity costs of serving peak demand.

The new demand charge encourages peak shaving; Battery storage reduced the plant’s demand charges; We separated demand and energy charges in the large C&I rate.

Demand Response (DR)

Programs where customers reduce or shift electricity use during peak or contingency events in response to price or incentive signals.

The aggregator enrolled 50 MW in DR for the summer; Critical peak pricing triggered voluntary DR; DR helped maintain reliability during the heat wave.

Distributed Energy Resources (DER)

Small-scale generation, storage, and controllable loads located near customers, such as rooftop PV, batteries, CHP, and EVs.

Hosting capacity maps guide DER interconnections; The VPP aggregated hundreds of DERs; DERs provided non-wires alternatives to a substation upgrade.

District Metered Area (DMA)

A hydraulically defined zone of a water distribution system with measured inflows to monitor consumption and detect leaks.

Night flows in DMA-12 signaled a hidden leak; We split the city into 24 DMAs to target NRW; Pressure management by DMA reduced bursts.

Drinking Water State Revolving Fund (DWSRF)

A federal-state program offering low-interest loans and assistance for drinking water infrastructure projects.

The utility closed a $20M DWSRF loan at 1.6%; DWSRF funded lead service line replacements; We bundled small projects to qualify for DWSRF financing.

Effluent

Treated wastewater discharged from a treatment facility to surface water, groundwater, or reuse systems.

The NPDES permit tightened effluent ammonia limits; We upgraded tertiary filtration to polish effluent; Reclaimed effluent irrigates the sports complex.

Energy Efficiency (EE)

Reducing energy use for the same service through technologies and practices, often delivered via utility DSM programs.

Heat pump incentives drove EE savings in winter; EE portfolios achieved 1.2% annual load reduction; EE and DR deferred a feeder upgrade.

Federal Energy Regulatory Commission (FERC)

The U.S. federal agency regulating interstate electricity markets and transmission, hydropower licensing, and interstate natural gas pipelines.

The project requires a FERC-jurisdictional interconnection; FERC Order changes impacted our capacity market revenues; The pipeline expansion filed a FERC certificate application.

Geographic Information System (GIS)

Spatial database and mapping tools used to inventory, analyze, and manage utility assets and networks.

GIS linked with our CMMS for work orders; We updated GIS after the main replacement project; GIS underpins 811 locate accuracy and as-built records.

Greenhouse Gas (GHG) Emissions

Emissions of gases such as CO2 and CH4 that contribute to climate change; utilities track, report, and reduce them.

The utility set a net-zero GHG target by 2050; Methane LDAR lowered gas system GHG intensity; Our resource plan assesses lifecycle GHG impacts.

Grid Modernization

Investments in automation, sensors, advanced controls, DER integration, and communications to improve reliability, resilience, and flexibility.

The grid mod plan includes ADMS and feeder automation; Non-wires alternatives are part of grid modernization; Grid mod funding supports hosting capacity analysis.

Hydraulic Modeling

Simulation of water or wastewater systems (e.g., using EPANET or sewer models) to evaluate pressure, flow, capacity, and water quality.

The model showed low residual pressure at peak hour; Sewer modeling revealed bottlenecks during I/I events; We calibrated the model with SCADA and field data.

Inflow and Infiltration (I/I)

Extraneous water entering sanitary sewers from stormwater inflow (connections) and groundwater infiltration (defects), reducing capacity.

Smoke testing identified inflow sources; I/I spikes overloaded the plant during storms; Lining laterals cut infiltration in Basin 3.

Integrated Resource Plan (IRP)

A long-term utility plan that evaluates demand forecasts and portfolios of supply- and demand-side resources to meet policy and reliability goals at least cost.

The IRP selected 500 MW solar plus storage; Stakeholders pushed for more EE in the IRP; IRP scenarios tested gas price and carbon policy risks.

Interconnection Agreement

A contract outlining technical, safety, and commercial requirements for connecting generation (including DER) to the grid.

The project executed a Level 2 interconnection agreement; IEEE 1547 compliance is required by the agreement; Queue position determines interconnection study timing.

Investor-Owned Utility (IOU)

A privately owned, for-profit utility regulated by state commissions, distinct from municipal or cooperative utilities.

The IOU filed a multi-year rate plan; Municipalization would shift assets from the IOU; IOUs often operate in vertically separated markets.

Kilowatt (kW) and Kilowatt-hour (kWh)

kW measures instantaneous power (rate of energy use), while kWh measures energy consumed over time.

The facility peaked at 500 kW and used 200,000 kWh; Demand charges bill on kW, energy charges on kWh; AMI data revealed a kW spike at shift start.

Leak Detection and Repair (LDAR)

Systematic programs to locate and fix leaks, commonly for gas pipelines and also for water distribution to reduce NRW and emissions.

Optical gas imaging supported LDAR surveys; Smart loggers accelerated water LDAR; LDAR cut methane emissions by 25% year-over-year.

Lead and Copper Rule Revisions (LCRR)

U.S. EPA updates requiring inventories of lead service lines, improved sampling, public notification, and accelerated lead line replacement.

We completed our LCRR service line inventory; The capital plan funds LCRR-compliant replacements; LCRR triggered outreach to schools for sampling.

Levelized Cost of Energy (LCOE)

A metric expressing the average cost per unit of electricity (e.g., $/MWh) over a project’s lifetime, including CapEx, OpEx, fuel, and financing.

Utility-scale solar LCOE was estimated at $45/MWh; LCOE helped compare wind vs. gas peakers; Sensitivities showed LCOE depends on capacity factor and WACC.

Load Factor

The ratio of average load to peak load over a period; indicates how efficiently capacity is utilized.

Improving load factor lowers per-kWh costs; Thermal storage boosted the campus load factor; The feeder’s load factor rose after TOU adoption.

Locational Marginal Pricing (LMP)

The price of electricity at a specific node in wholesale markets, reflecting marginal energy, congestion, and losses.

Day-ahead LMP at Bus 123 hit $300/MWh; Congestion lifted LMPs in the north zone; Negative LMPs occurred during high wind output.

Maximum Allowable Operating Pressure (MAOP)

The highest safe operating pressure for a gas pipeline segment, established by design, testing, and regulatory rules.

We hydrotested the main to confirm MAOP; Records verification was needed to substantiate MAOP; Anomalies reduced allowable MAOP until repairs.

Microgrid

A local energy system with generation, storage, and controls that can operate connected to the grid or islanded.

The hospital’s microgrid kept critical loads on during the outage; The campus microgrid participates in DR; We evaluated a microgrid as a resilience solution for PSPS events.

Million Gallons per Day (MGD)

A common unit for water and wastewater flow rates.

The WTP is rated at 25 MGD; Peak wet-weather flow reached 120 MGD; The reuse system offsets 2 MGD of potable demand.

National Pollutant Discharge Elimination System (NPDES)

U.S. permitting program that regulates point-source discharges to waters of the U.S., setting effluent limits and monitoring.

Our NPDES permit added nutrient caps; Noncompliance with NPDES triggered a consent order; We upgraded to meet new NPDES ammonia limits.

Net Metering

A policy allowing customers with generation (e.g., rooftop solar) to offset consumption with exports, usually credited at retail or an avoided-cost rate.

NEM 3.0 lowered export credits; The co-op moved from net metering to net billing; Net metering participation doubled after streamlined interconnection.

Non-Revenue Water (NRW)

Water produced but not billed due to leaks, theft, meter inaccuracies, or data errors; expressed as volume or percentage.

NRW dropped from 28% to 18% after leak repairs; We audited meter accuracy to reduce apparent losses; DMAs help quantify NRW at the zone level.

Operating Expenditure (OpEx)

Day-to-day costs such as labor, energy, chemicals, and maintenance that are expensed rather than capitalized.

Cloud OMS shifted spend from CapEx to OpEx; Chemical OpEx rose with PFAS treatment; Performance incentives target controllable OpEx.

Outage Management System (OMS)

Software that detects, predicts, and manages power outages using inputs from AMI, SCADA, and customer calls, supporting crew dispatch and ETRs.

OMS integrated AMI last-gasp events for faster triage; ETR accuracy improved after OMS upgrade; OMS heat maps guided patrols during the storm.

Performance-Based Regulation (PBR)

Regulatory approach tying utility earnings to outcomes (e.g., reliability, DER interconnections, affordability) rather than solely to cost recovery.

PBR metrics include SAIDI and interconnection timelines; Earnings adjust up/down based on PBR scorecards; PBR encourages non-wires solutions and EE.

Per- and Polyfluoroalkyl Substances (PFAS)

Persistent synthetic chemicals targeted for regulation in drinking water and wastewater; treatment often uses granular activated carbon (GAC), ion exchange (IX), or RO.

PFAS sampling found PFOA above proposed limits; GAC filters were installed for PFAS removal; Residuals handling considered PFAS disposal restrictions.

Power Purchase Agreement (PPA)

A contract where a buyer agrees to purchase electricity (and possibly RECs/attributes) from a generator under specified terms and pricing.

We signed a 20-year solar PPA at $0.03/kWh; The PPA includes a capacity payment; A virtual PPA hedges market price risk.

Public Utility Commission (PUC/PSC)

State regulatory bodies overseeing rates, service quality, and resource plans of investor-owned utilities; sometimes municipal/co-op issues too.

The PUC approved the rate case settlement; PSC staff recommended PBR pilots; Our IRP requires PUC approval before procurement.

Rate Base

The net value of utility plant in service on which an allowed return is earned, typically original cost minus accumulated depreciation plus certain additions.

AMI capitalization increased rate base; CWIP exclusion delayed rate base growth; Working capital was included in rate base per settlement.

Reliability Indices (SAIDI/SAIFI/CAIDI)

Standard electric reliability metrics: SAIDI (average outage minutes per customer), SAIFI (average number of interruptions per customer), and CAIDI (average duration of interruptions experienced).

SAIDI improved from 120 to 90 minutes after automation; Tree trimming lowered SAIFI; CAIDI rose during winter storms despite fewer events.

Supervisory Control and Data Acquisition (SCADA)

Industrial control systems that monitor and operate dispersed assets (e.g., pumps, substations) via remote telemetry, RTUs/PLCs, and HMI software.

SCADA alarms flagged low reservoir levels; We added redundant SCADA communications for resilience; SCADA trends informed pump energy optimization.