Within the zoning districts established by this chapter there exist lots, structures, uses of land and structures, and characteristics of use which were lawful before this chapter was passed or amended, but which are now prohibited, regulated, or restricted under the terms of this chapter, or shall be prohibited, regulated, or restricted under the terms of future amendment. In order to manage current and future nonconformities, it is the intent of this chapter to:

1.   Permit current nonconformities to continue until they are removed, but not to encourage their survival.

2.   Restrict any further nonconformities from being enlarged upon, expanded, or extended, or used as grounds for adding other structures or uses prohibited elsewhere in the same district.

3.   Consider legal, as of the date of adoption of this chapter, those structures which were nonconforming under the previous chapter, but which are now conforming under this chapter, and to allow such structures to be rebuilt, added to, or modified within the current terms and requirements of this chapter.

4.   Avoid undue hardship by deeming nothing in this chapter to require a change in the plans, construction, or designated use of any building on which actual construction was lawfully begun prior to the effective date of adoption or amendment of this chapter and upon which actual building construction has been carried on diligently. Actual construction is hereby defined to include the placing of construction materials in permanent position and fastened in a permanent manner.

5.   Deem as actual construction those projects where excavation or demolition or removal of an existing building has been substantially begun preparatory to rebuilding, provided that work shall be carried on diligently.