Except as otherwise required by the context, the following terms when used in this act shall be construed as follows:

1. "Agency" means the Adirondack park agency as created by chapter seven hundred and six of the laws of nineteen hundred seventy-one, and whose functions, powers and duties are provided for in article twenty-seven of the executive law.

2. "Commissioner" means the commissioner of environmental conservation, his successors in office and any agency which may succeed to the duties of such office.

3. "Development" means any activity which materially affects the existing condition, use or appearance of any land, structure or improvement including the actual or effective division or proposed division of land into lots, parcels or sites whether contiguous or not, for the purpose of sale, lease, license or any form of separate ownership or occupancy as part of a common scheme or plan, (including any grading, road construction, installation of utilities or other improvements or any other development preparatory or incidental to any such division) by any person or by any other person controlled by, under common control with or controlling such person or by any group of persons acting in concert as part of a common scheme or plan but shall not include the division of any land resulting from bona fide devise, inheritance, gift or the lease of land for hunting and fishing.

4. "Forest Management" means forestry practices, including harvesting of a forest woodland or plantation, the construction, alteration or maintenance of wood roads, skidways, landings and fences and related research and educational activities.

5. "Free flowing" means existing or flowing in natural condition without impoundment, diversion, straightening, riprapping, or other modification of the waterway, except for stream improvement structures for fisheries management purposes expressly authorized in section 15-2709 of this chapter.

6. "Improvement" means any change in or addition to land, including but not limited to grading, filling, excavating or adding banks, fences, dikes, ditches, pipelines, poles, electrical conduits, roads, streets, curbs, gutters, sidewalks, driveways, parking lots or spaces.

7. "Motor vehicle" means a device for transporting personnel or material, incorporating a motor or an engine of any type for propulsion and with wheels, tracks, skids, skis, air cushion or other contrivance for traveling on, or adjacent to land and water or through water.

8. "Person" means any individual, corporation, partnership, joint venture, association, organization, government or any agency or political subdivision thereof, or any other entity.

9. "River" means a flowing body of water or a section, portion or tributary thereof, including rivers, streams, creeks, runs, kills, rills, branches, or lakes. "River area" means the term river and the land area in its immediate environs as established by the commissioner or the agency, but not exceeding a width of one-half mile from each bank thereof.

10. "Road" means any highway, hard-surfaced road, improved or dirt road.

11. "Stream improvement structures for fishery management purposes" means structures and improvements, including but not limited to, fish barrier dams, fish passage structures, minor diking, cribbing, bank stabilization and stream deflectors and other structures or improvements designed solely for fishery management purposes which do not materially alter the natural character of the waterway.

12. "Structure" means any object constructed, installed or parked on land to facilitate land use, such as buildings, mobile homes, sheds, signs, tanks, outdoor lighting and any fixtures, additions and alterations thereto and trailers, travel trailers, campers, or tents constructed, installed, or parked on land for other than a temporary period or for a purpose other than transient occupancy and any fixtures, additions or alterations thereto.

13. "System" means the rivers designated as wild, scenic and recreational rivers in this part.