SD1 Glossary

Amended Consent Decree (ACD): Renegotiated agreement between SD1 and state and federal regulators regarding enforcement of the Clean Water Act. The ACD establishes sanitary sewer overflow (SSO) and combined sewer overflow (CSO) mitigation goals on five-year intervals, with a final deadline of January 1, 2040, to eliminate all typical-year SSOs and recapture at least 85 percent of typical-year CSOs. (See Consent Decree; Clean H2O40)

Backflow Prevention Device: Any mechanical device or devices, such as a backflow preventer valve or pump, designed to prevent sewer backups. (See Backup Assistance Program)

Backup Assistance Program (BAP): An SD1 program that provides financial assistance to help property owners who are impacted by basement backups install a backflow prevention device.

Base Rate: A base fee paid by all SD1 residential sanitary sewer customers to help cover the costs of conveying and treating wastewater. The base rate includes the first 2 hundred cubic feet of wastewater treatment.

Best Management Practice (BMP): Any management practice designed to reduce pollution entering a waterway. These practices can be structural, such as rain gardens and silt fences, which require construction, installation and maintenance. They can also be nonstructural, such as ordinances or educational materials, which involve changes in activities or behaviors of people.

Biosolids: Solid materials resulting from wastewater treatment that meet government criteria for beneficial use, such as for fertilizer.

Bypass: A flow relief point in a sewer system that diverts high flows from an overwhelmed system to a river, creek or storm sewer.

Capacity, Management, Operations and Maintenance (CMOM): A flexible, dynamic framework for municipalities to identify and incorporate widely-accepted wastewater industry practices to better manage, operate and maintain collection systems; investigate capacity constrained areas of the collection system; and respond to sanitary sewer overflow events.

Categorical Industrial User (CIU): A type of significant industrial user (SIU) subject to categorical pretreatment standards. CIUs are regulated under federal rules in Title 40 CFR 401-424 and 425-471 and/or are assigned either pretreatment limitations, reporting requirements or both by the US Environmental Protection Agency. (See Significant Industrial User)

Certified Tapper: A person licensed and approved by SD1 to connect a building to the wastewater or storm water sewer system. 

Clean H2O40: A partnership between SD1, the US Environmental Protection Agency and the Commonwealth of Kentucky to increase SD1’s capacity to better manage the flow of wastewater and storm water in Northern Kentucky through a number of strategic projects specifically designed to address sewer overflows. By the year 2040, SD1 will completely eliminate typical-year sanitary sewer overflows and recapture at least 85 percent of all typical-year combined sewer overflows.

Clean Water Act: A federal law that establishes the basic structure for regulating discharges of pollutants into the waters of the United States and regulating quality standards for surface waters.

Co-Permittee: An owner or operator of a municipal storm sewer that has co-applied for permit coverage with another permittee, and that is only responsible for permit conditions relating to the discharge for which it is operator. (See National Pollutant Discharge Elimination System (NPDES); Municipal Separate Storm Sewer System (MS4) Program)

Collection Systems: The system of underground pipes and maintenance structures that are used to convey wastewater to a wastewater treatment facility.

Combined Sewer Overflow (CSO): A discharge from a combined sewer system at a point prior to the publicly owned treatment works treatment plant.

Combined Sewer System (CSS): A wastewater collection system which conveys sanitary wastewaters and storm water through a single pipe system to a publicly owned treatment works.

Comprehensive Annual Financial Report (CAFR): A set of financial statements comprising the financial report of a state, municipal or other government entity that complies with the accounting requirements promulgated by the Governmental Accounting Standards Board. The CAFR is audited by an external accounting firm utilizing GASB requirements.

Consent Decree: An agreement or settlement that resolves a dispute between two parties without admission of guilt (in a criminal case) or liability (in a civil case). On this website, references to a consent decree generally refer to an agreement between SD1 and state and federal regulators regarding enforcement of the Clean Water Act.

Culvert: A culvert is a structure that allows water to flow under a road, railroad, trail, or similar obstruction from one side to the other.

Dental Amalgam: The mixture of mercury, silver and copper used to fill cavities caused by tooth decay. To learn more, visit the Dental Amalgam Program page.

Detention Basin: A constructed pond that is designed for temporary storage and slow release of storm water runoff generated from impervious surfaces. Also known as "dry ponds," detention basins typically remain dry between storm events. (See Best Management Practice)

Disconnection, Redirection, Infiltration Program (DRIP): An SD1 program that provides homeowners with step-by-step guides to help them implement methods of managing storm water runoff in their own yards and neighborhoods.

Downspout Disconnection: In many areas, residential downspouts are piped into the ground and connect to the combined sewer system or the separate storm sewer system. In other areas, downspouts are discharging directly onto the ground. Downspout disconnection is the removal of the lower portion of your home’s downspout and adding an extension that allows you to control where the water is discharged on your property. (See Best Management Practice; Disconnection, Redirection, Infiltration Program (DRIP))

Effluent: Wastewater treatment effluent is the final product from a wastewater treatment plant that discharges into a river or the sea. 

Environmental Surcharge: A fee paid by all residential sanitary sewer customers to help fund SD1’s Clean H2O40 overflow mitigation program, as required under the federal Clean Water Act. This fee will disappear when SD1’s overflow mitigation program is complete. (See Clean H2O40)

Equalization (EQ) Tank: A large holding tank that allows wastewater flow to be equalized over a specific period of time, allowing for controlled release back into the public sewer system, reducing or eliminating sanitary sewer overflows.

Equivalent Residential Unit (ERU): Storm water customers are billed based on impervious surface area. Residential customers (detached single-family homes and duplexes on a single parcel) pay a flat monthly fee for one “equivalent residential unit,” which is based on the average impervious surface area for a Northern Kentucky residential property – currently 2,600 square feet. Non-residential customers are billed based on actual impervious surface area, in ERU units of 2,600 square feet.

Erosion: Erosion is the wearing away of land by natural forces such as wind and water. Even though erosion is a natural process, it can be increased or decreased by human activity. For example, impervious surfaces increase the speed of storm water runoff, increasing erosion. 

Fats, Oils and Grease (FOG) Program: A program designed to protect the public sewer system from the discharge of excess fats, oil and grease by ensuring that food service establishments are in compliance with the requirements of SD1 Rules and Regulations, as well as commitments made by SD1 in the Capacity, Management, Operations and Maintenance (CMOM) Self-Assessment under the original consent decree.

Food Service Establishment (FSE): Any establishment, business, facility or user engaged in preparing, serving or making food available for consumption. Single family residences are not a FSE.

Fiscal Year: A one-year period companies and governments use for financial reporting and budgeting. SD1’s fiscal year begins July 1 and ends June 31.

Flood Pump Station: Facilities along the banks of the Ohio and Licking rivers that operate when the rivers are at elevated levels. To prevent elevated river water from flowing in a reverse direction up pipe outfalls and creating surface flooding, the outfall pipes are closed and the flood pump stations are then used to pump any water on the dry side of the earthen levees or flood walls and discharge on the wet side.

Geographic Information Systems (GIS): A framework for gathering, managing and analyzing data. Rooted in the science of geography, GIS integrates many types of data. It analyzes spatial location and organizes layers of information into visualizations using maps and 3D scenes.

Grease Control Equipment (GCE): A devices that prevents fats, oils and grease from entering the wastewater sewer system. SD1 requires food service establishments install and maintain either a grease trap or interceptor. (See Fats, Oils and Grease (FOG) Program and Food Service Establishment (FSE))

Hauled Waste: Waste transported to a wastewater treatment plant by tanker truck rather than through underground pipes. SD1 permits waste haulers. 

Household Hazardous Waste (HHW): Any leftover household product that contains corrosive, toxic, ignitable or reactive ingredients. Check our calendar for annual household hazardous waste collection event dates. 

Hundred Cubic Feet (HCF): SD1’s sanitary sewer billing is based off water usage, as measured in hundred cubic feet. One hundred cubic feet is the equivalent of 748 gallons of water.

Hydromodification: The physical and sometimes functional alteration of water bodies, including through channelization, damming and stream bank or shoreline erosion.

Illicit Discharge: Any discharge to the municipal storm water sewer system that is not composed entirely of storm water, except for discharges allowed under a National Pollutant Discharge Elimination System (NPDES) permit. (See National Pollutant Discharge Elimination System (NPDES))

Impervious Surface: Any surface such as rooftops, driveways, roadways, sidewalks and parking lots that prohibit or significantly restrict the passage of precipitation into the subsurface soils.

Infrastructure: Infrastructure refers to a network of pipes, manholes, wastewater treatment plants, storm water control features and other components of the wastewater and storm water sewer system. 

Kentucky Division of Water (KDOW): The Division of Water’s mission is to “manage protect and enhance the quality and quantity of the Commonwealth’s water resources for present and future generations through voluntary, regulatory and educational programs.”

Manhole: A structure that is placed at changes in direction and elevations of the sewer system. Manholes are used as access for cleaning the sewer system and other maintenance activities.

Million Gallons per Day (MGD): The standard measure of wastewater flow through treatment plants.

Municipal Separate Storm Sewer System (MS4) Program: A program regulated by the US Environmental Protection Agency as part of the Clean Water Act to improve the nation’s waterways by reducing the quantity of pollutants that storm water picks up and carries into storm sewer systems during rain events and snow melts. Urban communities and counties regulated through the MS4 program are required by law to manage storm water quality.

National Pollutant Discharge Elimination System (NPDES): The Clean Water Act prohibits anyone from discharging pollutants through a point source into a water of the United States unless they have an NPDES permit. The permit contains limits on what can be discharged, monitoring and reporting requirements, and other provisions to ensure that the discharge does not impair water quality or harm public health. (See Co-Permittee)

Nonpoint Source Pollution: Pollution originating from runoff from diffuse areas (land surface or atmosphere). Nonpoint source pollution is a major contributor to contamination in Kentucky’s waterways. When rainfall or snowmelt moves over and through the ground, it picks up and carries away natural and human-made pollutants, finally depositing them into streams, lakes, wetlands and ground waters.

Outfall: An outlet point where water flows from a structure (e.g. pipe outlet) and the area immediately beyond the structure which is impacted by the velocity of flow in the structure.

Paymentus: SD1’s payment processing partner, offering a variety of ways to pay your SD1 bill, including by telephone, auto withdrawal, online one-time, e-bill, a mobile app, in person, at drop box locations across Northern Kentucky, by mail or at all Northern Kentucky BB&T branch locations.

Point Source Pollution: Pollution that can be traced to a single point source such as a pipe or culvert (e.g. industrial, wastewater treatment plant, and municipal storm water discharges).

Private Cost-Share Program: Assists co-permittees in addressing private storm water issues that may have a public impact. Only co-permittees may apply.

Private Sewer Lateral: The portion of the sewer network that connects individual and private properties to the public sewer system. Private sewer laterals are owned and maintained by the property owner, not SD1.

Public Cost-Share Program: Assists co-permittees with new storm water infrastructure that addresses drainage issues associated with a dedicated and accepted right-of-way, impacting a right-of-way, or caused by or related to public infrastructure drainage.

Public Culvert Cost-Share Program: Assists co-permittees with public culverts owned and maintained by the co-permittee that are associated with a dedicated right-of-way in the storm water service area and are in need of capital improvement such as repair or replacement. The program does not apply to maintenance-related activities.

Publicly Owned Treatment Works (POTW): A sewage treatment plant that is owned, and usually operated, by a government agency such as SD1.

Public Service Park: Educational facility located in and around SD1’s main office that teaches visitors about storm water challenges and solutions. The park provides an interactive learning experience and features 10 best management practices for controlling storm water runoff. The park is open from 8 a.m. to dusk, seven days a week.

Pump Station: A facility used for pumping wastewater from a lower to higher elevation, particularly where the elevation of the source is not sufficient for gravity flow and/or where the use of gravity conveyance will result in excessive excavation and higher construction costs.

Rain Barrel: A container, placed under a downspout, which is used to collect rainfall running off a roof and store it for future use. (See Best Management Practice; Disconnection, Redirection, Infiltration Program (DRIP))

Rain Garden: A shallow depression of land that is planted with native wetland or wet prairie wildflowers and grasses. (See Best Management Practice; Disconnection, Redirection, Infiltration Program (DRIP))

Request for Final Determination Form: A form to request a reconsideration of SD1’s existing sanitary or stormwater service policies, including sanitary sewer leaks and winter factor adjustments, property classifications, storm water boundary disputes, and nonresidential ERU calculations. The Request for Final Determination form replaces the Request for Reduced Sewer Service (RRSS) form.

Residential User: Any contributor to SD1’s wastewater sewer system whose lot, parcel, real estate, or building is used for domestic dwelling purposes only.

Retention Basin: A constructed pond that is designed for temporary storage and slow release of storm water runoff generated from impervious surfaces. Also known as "wet ponds," retention basins typically maintain a permanent pool of water, even between storm events. (See Best Management Practice)

Riparian Zone: The forested or vegetated land along the banks of streams. These zones are important natural filters, protecting streams from excessive sedimentation, polluted surface runoff and erosion. (See Best Management Practice)

Sanitary Sewer Overflow (SSO): The intentional or intentional diversion of flow from a sanitary sewer collection system that occurs before the head works of a sewage treatment plant. SSOs include discharges to waters of the United States as well as diversions to public or private property and the environment that do not reach waters of the United States, such as basement flooding.

Sanitation: The treatment, cleaning and proper disposal of wastewater.

Sediment: Any solid particulate matter that can be transported by water flow. Types of sediment include loose soils, sand, minerals and hard parts of dead organisms. These sediments are carried to streams by storm water runoff and remain suspended in the water or settle to the bottom of the stream bed. Other pollutants such as phosphorus, pathogens and heavy metals are often attached to the soil particles and wind up in the water bodies with the sediment.

Separate Sanitary Sewer System: A wastewater collection system which conveys sanitary wastewater through a pipe system to a publicly owned treatment works.

Separate Storm Sewer System: A conveyance or system of conveyances, including but not limited to any street curbs and gutters, storm drains, pumping facilities and other drainage structures designed or used for collecting or conveying storm water.

Septic Tank System: An underground chamber made of concrete, fiberglass or plastic through which domestic wastewater flows for basic treatment. Common in areas with no connection to the public sewer system, the septic system decomposes waste material with the use of anaerobic bacteria.

Significant Industrial User (SIU): Industrial users of the public sewer system that have potential to adversely affect SD1 treatment plants, discharge a daily average of 25,000 gallons of processed wastewater, or contribute 5 percent or more of the average dry-weather hydraulic or organic capacity of an SD1 wastewater treatment facility.

Single Family Residential Development: A building containing one or two independent dwelling units, each of which is occupied by no more than one family, and 2) all condominiums and landominiums intended for sale to individual unit owners. 

Silt Fence: A temporary sediment barrier made of woven, synthetic filtration fabric supported by either wood or steel posts, designed to prevent the flow of sediment from leaving the desired site and entering streams or storm drainage systems by slowing storm water runoff and causing the sediment to be deposited at the silt fence boundary. (See Best Management Practice)

Sewage: See “Wastewater.”

Special Discharge: Also known as an unusual or one-time discharge, a special discharge is wastewater from an industrial user that does not fit into another category. All special discharges must be approved by SD1’s Industrial Pretreatment Department before they are released into the public sewer system.

Special Meter: A credit meter designed to measure the quantity of water not actually entering the wastewater treatment system from a nonresidential property. 

Splash McClean: Splash McClean is SD1’s fish mascot. Splash helps children understand how human behavior can affect fish and wildlife habitats. To learn more, visit Mascot Visits and Presentations. 

Storm Drain: Designed to drain excess rain and groundwater from paved streets, parking lots, sidewalks and roofs.

Storm Frequency: Statistical techniques can be used to estimate the probability of the occurrence of a given storm, and this is presented as storm frequency. For example, if the probability of a storm is determined to be once every two years, then the storm is said to be a "two-year storm." Please note, however, that multiple "two-year storms" can occur within a given year or even a given week - storm frequency is just a statistical probability.

Storm Water Fee: Fee paid by all customers within the storm water boundary to fund SD1’s storm water management program that keeps roadways safe and passable during wet weather events and protects local waterways from pollution.

Storm Water Management Program: The regional program administered by SD1 to operate and maintain the public storm water system to address local flooding and drainage issues and to implement the storm water quality management program to fulfill Phase II MS4 regulatory requirements.

Storm Water Quality Management Plan: The written plan that details the Storm Water Quality Management Program for a defined period of time. The plan is considered a single document, even though it actually consists of separate programs.

Storm Water Quality Management Program: A comprehensive program to manage the quality of storm water discharged from the municipal storm sewer system (MS4).

Storm Water: Any surface runoff or discharge consisting entirely of water from any form of natural precipitation and resulting from such precipitation (e.g. runoff resulting from rainfall or snow melt).

Surcharge: The charge industrial users must pay in addition to sanitary sewer service charges if their wastewater discharge into the sewer system exceeds the specifications for the normal strength sewage. (See Significant Industrial User (SIU); Categorical Industrial User (CIU)).

Swale: A low-lying, shallow channel with gently sloping slides to convey storm water. Swales can be natural or manmade.

System Capacity: the overall capacity of the sanitary or storm water system as determined periodically by the District in accordance with standard engineering calculations and regulations of the Kentucky Division of Water (KDOW).

Technical Assistance Program: Provides engineering and planning-level assistance (i.e. concept-level studies) to co-permittees when communities need help identifying problems and/or potential solutions to storm water-related issues. This program is not for detailed construction design, but merely for identifying planning-level solutions when a simple improvement or other solution is not apparent.

Tributary: A river or creek that flows into a larger stream or lake. Each tributary drains a different watershed, carrying runoff and snowmelt from that area. In SD1’s service area, the Licking River is just one example of an Ohio River tributary. (See Watershed)

Variable Rate: The charge for residential sanitary sewer customers who require wastewater treatment beyond the 2 hundred cubic feet included in the base rate. The variable rate is charged per each additional hundred cubic feet of wastewater treatment. (See Base Rate; Winter Factor)

Wastewater: Water that has been used in a home, business or as part of an industrial process. Typically the water that goes down the drain while showering, washing dishes or laundry, etc.

Watershed: An area of land where all water drains, or “sheds,” to the same stream, lake or other body of water.

Watershed Plan: A strategy and work plan for achieving the goals established in the Amended Consent Decree that provides assessment and management information for geographically defined watersheds in Northern Kentucky.

Winter Factor: SD1’s method for determining water usage for sanitary sewer billing. To ensure that outdoor activities such as washing your car or watering your lawn – which do not send water to SD1’s sewer system – are not included in sanitary sewer billing, SD1 works with local water districts to measure water usage during a 90-day period between November and April. A customer’s variable rate is then set in July for the next 12 months based on their winter usage during this 90-day period.