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Glossary beginning with I

terms for which definitions are available


weakening, damage, or instability, such as the effects caused by pollution


incapable of being penetrated, such as a surface that does not absorb water


development that occurs on smaller parcels that remains undeveloped but is within or in very close proximity to urban or densely developed areas; usually relies on existing infrastructure and does not require an extension of water, sewer, or other public utilities


movement of surface water into the soil, where it is absorbed by plant roots, evaporated into the atmosphere, or percolated downward to recharge groundwater


the basic system of utilities and services needed to support a society; structures such as culverts, pipes, bridges, dams, and flood control measures can cause instability of streams and affect aquatic habitats


the upstream end of any structure through which water may flow


unable to pass into solution


animals, such as insects and crustaceans, that lack backbones (vertebrae)


Ingetrated Watershed Management Plan