Condition where free oxygen is present

Algae Blooms
A growth of algae resulting from excessive nutrient (nitrogen or phosphorus) levels or other physical and chemical conditions that enabled algae to reproduce rapidly. The overgrowth of algae can form scums and mats, and reduce the amount of oxygen as they decay.

Condition where free oxygen is not present or is unavailable

Of, relating to, or resulting from the influence of human beings on nature

Geologic formations (rock, sand, or gravel) that are saturated and sufficiently permeable to yielding significant quantities of water

Reduce the force or amount or magnitude

Occurring at the bottom of the sea or lake (e.g. benthic organisms)

A measure of the amount of living matter per unit area or volume of habitat

Cluster System
A wastewater collection and treatment system where two or more facilities, but less that an entire community, is served

Cultural Eutrophication
The accelerated aging process of water bodies resulting from human sources of nutrients that stimulate the growth of aquatic plants and lead to the depletion of dissolved oxygen

They system of living organisms that interact with one another and their physical environment, functioning as an ecological unit

Treated or untreated wastewater from a treatment facility or unit that is discharged into the environment

A bay or a conformation resembling a bay. The terms embayment and estuary are used interchangeably in this guidance

Partially enclosed body of water that consists of fresh and saltwater where the tide meets the river’s current (see embayment)

A waterbody’s natural aging natural aging process due to enrichment in dissolved nutrients that stimulate the growth of aquatic plant life, usually resulting in the depletion of dissolved oxygen

Innovative/Alternative (IA) System
Advanced on-site wastewater treatment and disposal systems that provide additions or alternatives to one or more of the components of a conventional system while providing at least an equivalent degree of environmental and public health protection. I/A systems are becoming more widely used, particularly for cost-effective upgrades of failing systems on difficult sites that cannot accommodate a conventional system. I/A technologies also are used for enhanced treatment to reduce nitrogen sensitive areas

Invasive Species
Aggressive and spreading plants or animals that do not naturally occur in a specific area and whose introduction may cause economic or environmental harm

Massachusetts Clean Waters Act
MGL c.21, § 26-53, which prohibits the discharge of pollutants to waters of the Commonwealth without a permit, unless exempted by regulation

Massachusetts Estuaries Project

To take corrective action to eliminate pollution or reduce its impact

Component of fertilizer. Considered a broad indicator of the contamination of groundwater. The nitrogen species in marine systems that is most responsible for eutrophication

Nitrogen Cycle
Continuous cyclic progression of chemical reactions in which atmospheric nitrogen is compounded, dissolved in rain, deposited in the soil, assimilated and metabolized by bacteria and plants, and returned to the atmosphere by organic decomposition

Nitrogen Loading
The input of nitrogen to estuaries and embayments from natural and anthropogenic sources

Any substance required by plants and animals for normal growth and maintenance e.g. nitrogen and phosphorus

Point Source
Pollution from discernible, confined, and concrete conveyances, including but not limited to any pope, ditch, channel, tunnel, conduit, well discrete fissure, container, rolling rock, concentrated animal feeding operation, vessel or other floating craft from which pollutants are or may be discharged. This term does not include return flows from irrigation agriculture

The measure of the salt content of water

Mineral and organic material that settles from suspension in the water column

Septic Tank
A buried tank designed to receive and pretreat wastewater from individual homes by separating settleable and floatable solids from wastewater. A component of an on-site wastewater treatment and disposal system

Sequencing Batch Reactor (SBR)
Wastewater treatment technology in which aeration and clarification are carried out sequentially in the same tank

The water-carried human or animal wastes from residences, buildings, industrial establishments, or other places, together with such ground water infiltration and surface water as may be present

The University of Massachusetts School of Marine Science and Technology

Tidal Flushing
The exchange of water from an estuarine system to the waterbody into which it empties

Total Mazimum Daily Load (TMDLs)
The greatest amount of a pollutant that a waterbody can accept and still meet water quality standards for protecting public health and maintaining the designated beneficial uses of those waters for drinking, swimming, recreation and fishing

A measure of soil or organic particles that cloud the water and do not allow light rays to pass through

Water Column
The open-water environment, as distinct from the bed or shore that may be inhabited by marine or fresh water organisms

Wetlands Protection Act (WPA)
MGL c.131, §40. Under the provisons of the Act, no person may remove, fill, dredge, or alter certain resource areas without first filing a Notice of Intent and obtaining an Order of Conditions. The Act requires that the Order contain conditions to contribute to the following interests: protection of public and private surface and ground water supply, flood control, storm damage prevention, prevention of pollution, protection of fisheries, land containing and protection of wildlife habitat