Bid / Contract Award – Project owner’s notice to a bidding contractor of the acceptance of the submitted bid.
Biofiltration – The process of reducing pollutant concentrations in water by filtering the polluted water through biological materials.
Detention – The release of stormwater runoff from the site at a slower rate than it is collected by the stormwater facility system, the difference being held in temporary storage.
Embankment – A structure of earth, gravel, or similar material raised to form a pond bank or foundation for a road.
Green Remediation – the practice of considering all environmental effects of remedy implementation and incorporating options to minimize the environmental footprints of cleanup actions
Groundwater – Water in a saturated zone or stratum beneath the land surface or beneath a surface water body.
Infiltration – The downward movement of water from the land surface to the subsoil.
MTD – Manufactured Treatment Device (MTDs) are a subset of BMPs. These are treatment BMPs that are manufactured and sold by businesses as stand-alone treatment systems and don’t typically have available information on treatment capabilities like more generic BMPs such as swales and wet ponds.
Retention – The process of collecting and holding surface and stormwater runoff with no surface outflow.
Secchi Disk – The Secchi disk, as created in 1865 by Angelo Secchi, is a plain white, circular disk 30 cm in diameter used to measure water transparency or turbidity in bodies of water. The disc is mounted on a pole or line, and lowered slowly down in the water
Scope of Work – The division of work to be performed under a contract or subcontract in the completion of a project, typically broken out into specific tasks with deadlines.
Sedimentation – The depositing or formation of sediment.
Special Conditions – Provisions of a contract that are peculiar to the project under consideration and do not fall under the general conditions or supplementary conditions.
Subgrade – A layer soil used as the underlying base for a BMP.
 Western Washington Stormwater Manual
Glossary Lookup List