For the purposes of this chapter, the Township of Upper Uwchlan is hereby divided into the following classes of districts:

The location and boundaries of such districts shall be as shown on the map hereby made a part of this chapter, which map shall be designated the "Zoning Map of Upper Uwchlan Township." The said map, and all the notations, references, and other data shown hereon, shall be as much a part of this chapter as if fully described herein and shall be kept at the Township offices.

The boundaries between districts are, unless otherwise indicated, either the center lines of streets, lanes, watercourses and rights-of-way of power lines, pipe lines, and other public utilities. Where boundaries of a single district are indicated as including directly opposite sides of a street, lane, lake or watercourse, or right-of-way of a power line, pipe line, or other public utility, for any portion of its length, the district so indicated shall be construed to apply to the entire bed of such feature named lying within such portion of its length. Where uncertainty exists as to the location of any such boundary as shown on the Zoning Map, the following rules shall apply:

Where a lot is divided by a district boundary line, other than a boundary line of the Flood Hazard District, the uses permitted in the less restrictive district may extend into that portion of said lot in the more restrictive district to the nearest lot line, but in no case a greater distance than 50 feet, so long as full use is made of the less restricted area before extension into the more restricted area of the said lot; and provided, however, that the area and bulk regulations of the less restrictive district shall not be so extended, and further provided that in no case shall the uses permitted in an abutting district be extended for any distance into a Flood Hazard District.