To qualify for such protection, a nonconforming use must lawfully exist at the time the restriction is adopted and have continually existed since that time. Arsenault v. Keene, 104 N.H. 356, 358-59, 187 A.2d 60, 62 (1962). In keeping with the general policy of zoning law to carefully limit the extension and enlargement of nonconforming uses, we strictly construe provisions that permit the continuance of such uses.

The law is well established that a nonconforming use is permissible only where it legally exists at the date of the adoption of the zoning ordinance. Town of Derry v. Simonsen, 117 N.H. 1010, 1016, 380 A.2d 1101, 1105 (1977); Arsenault v. Keene, 104 N.H. 356, 358, 187 A.2d 60, 62 (1962). This rule of law is based on the principle that "`[p]rovisions which except existing uses are intended to favor uses which were both existing and lawful, not to aid users who have succeeded in evading previous restrictions.'"

[4-6] Nonconforming uses relate to conditions which exist prior to the time a zoning ordinance is passed. RSA 674:19; Arsenault v. Keene, 104 N.H. 356, 358-59, 187 A.2d 60, 62 (1962). A nonconforming use is a use in fact existing on the land at the time of adoption of the ordinance.

Dumais v. Somersworth, 101 N.H. 111, 115; Annot., 6 A.L.R.2d 960." Arsenault v. Keene, 104 N.H. 356, 357, 187 A.2d 60, 61 (1962). Though the cited authority relates to problems involving vested rights arising from the issuance of building permits as opposed to the creation of such rights by means of subdivision approval, the governing principles are substantially similar.

In the 1960s, the town rezoned the district to its present residential/agricultural status, and Siergiewicz lawfully continued to operate his enterprise as a nonconforming use. See Arsenault v. Keene, 104 N.H. 356, 358-59, 187 A.2d 60, 62 (1962). Though the parties dispute whether, at the time the district was rezoned, Siergiewicz maintained his business on both lots, the record clearly shows that the large barn on lot 43 comprised the bulk of his operations.

A controlling policy of zoning law is to carefully limit the extension and enlargement of nonconforming uses. Arsenault v. Keene, 104 N.H. 356, 359, 187 A.2d 60, 62 (1962); cf. Keene v. Blood, 101 N.H. 466, 469, 146 A.2d 262, 264 (1958) (provisions permitting change in nonconforming uses are strictly construed). In this area, the ultimate purpose of zoning regulations is to reduce nonconforming uses to conformity as quickly as possible.

See, e.g., Adams v. Bradshaw, 135 N.H. 7, 14, 599 A.2d 481, 486 (1991) ("a property owner has no vested right in a sewer connection" and at most acquires a license), cert. denied, ___ U.S. ___, 112 S.Ct. 1560 (1992); Vachon Son, Inc. v. Concord, 112 N.H. 107, 109-10, 289 A.2d 646, 648 (1972) (no vested rights in a zoning classification); Glick v. Town of Ossipee, 130 N.H. at 646, 547 A.2d at 233 (town road may be discontinued by a vote of the town). Consequently, estoppel would not normally be available to the plaintiffs here, see Arsenault v. Town of Keene, 104 N.H. 356, 187 A.2d 60 (1962) (no rights created by use which was illegally established); Parkview Associates v. City of New York, 71 N.Y.2d 274, 279, 519 N.E.2d 1372, 1373, 525 N.Y.S.2d 176, 176 ("estoppel is not available to preclude a governmental entity from discharging its statutory duties or to compel ratification of prior erroneous implementation in the issuance of an invalid building permit"), cert. denied and appeal dismissed, 488 U.S. 801 (1988), especially where the lack of estoppel would not result in the loss of the plaintiffs' property. Nevertheless, unlike Dumais v. Somersworth, where the facts of the situation were clear and easily discoverable, here a reasonably diligent inquiry would not have disclosed that Garland Road was a class VI highway.

In re John Kevin B., 129 N.H. 286, 288, 525 A.2d 281, 283 (1987) (quoting King v. Town of Lyme, 126 N.H. 279, 284, 490 A.2d 1369, 1372 (1985)); Theresa S. v. Sup't of YDC, 126 N.H. 53, 55, 489 A.2d 592, 593 (1985). All of the sections of a statute must be construed together, Blue Mountain Forest Ass'n v. Town of Croydon, 119 N.H. 202, 204, 400 A.2d 55, 57 (1979), and "not viewed separately in isolation," Arsenault v. Keene, 104 N.H. 356, 358, 187 A.2d 60, 62 (1962). [6, 7] Reading RSA 151-C:13, I(e) (Supp. 1987) in the context of RSA chapter 151-C leads to the conclusion that the aim of section (e) is to exempt from CON review an increase or conversion of a few beds in a residential facility that has either already received a CON for its larger operation or that is too small to be subject to the CON requirement.

[4-6] "[I]t is `the general policy of zoning to carefully limit the extension and enlargement of nonconforming uses.'" Wunderlich v. Town of Webster, 117 N.H. 283, 286, 371 A.2d 1177, 1179 (1977) (quoting Arsenault v. Keene, 104 N.H. 356, 359, 187 A.2d 60, 62 (1962)); see 6 P. ROHAN, ZONING AND LAND USE CONTROLS 41.03 [3][a] (1978). In discussing the need for communities to develop comprehensive or master plans as guidelines for local growth, we stated that "[t]owns may not refuse to confront the future by building a moat around themselves and pulling up the drawbridge."

Such an interpretation could create a flood of nonconforming uses in Derry and make a shambles of its zoning ordinance. The defendant primarily builds his case around a one sentence dictum in Arsenault v. Keene, 104 N.H. 356, 187 A.2d 60 (1962). In Arsenault, the plaintiffs, who had purchased their property in 1949, converted a two apartment residence into four apartments in violation of the then existing city of Keene zoning ordinance.