*499 OPINION
By the Court,
In this action, sounding both in inverse condemnation and in tort, the district court found that the County of Clark and the *500 Clark County Flood Control District (hereinafter collectively referred to as “the County”), had, by acting in conjunction with various private parties, 1 caused large amounts of water to be cast upon the property of the Powers, the Wallaces, and the Lowes. 2 The County appeals from the judgment awarding just compensation and damages. We affirm.
During the 1950’s and early 1960’s, respondents acquired Various properties in Clark County, and developed those lands for residential use. The land was desert terrain, sandy and porous, and sloped gently downhill in an easterly direction. An ephemeral stream or wash, one which flows only in direct response to precipitation in the immediate locality, traversed the Powers parcel. The land immediately west of the Powers and Lowe parcels was sufficiently porous to absorb and dissipate most rain waters. Heavy rains, however, would collect in the low, surrounding areas, and would follow the natural terrain, entering the Powers and Lowe properties at the approximate border between the two properties. Due to the gentle slope, these waters would flow, if at all, at a slow current, and would be naturally dissipated and absorbed. Flooding was rare. This ephemeral stream paralleled a much larger wash, the Flamingo Wash, which runs south of the instant parcels. Prior to 1967, the flow, if any, of rain, nuisance, and flood waters did not damage the respondents’ parcels, nor did it restrict the use and development of the land.
Commencing in 1967, the development of the lands west of respondents’ parcels resulted in the alteration, diversion, channeling, and acceleration of rain, nuisance, underground, and flood waters onto respondents’ properties. The County participated actively in the development of these lands, both by its own planning, design, engineering, and construction activities and by its adoption of the similar activities of various private developers as part of the County’s master plan for the drainage and flood control of the area.
As part of the County’s master plan, the land at the intersection of Desert Inn Road and Eastern Avenue was filled, leveled, graded, compacted, and paved. The County elevated Topaz Street, which divided the developed properties from the Lowe and Powers parcels, by four feet, and raised the land *501 west of Topaz Street to a new level. Leach lines and beds were constructed to collect and divert waters from a grocery store site, channeling those waters to a drainage pipe maintained by the County and from there to a sump hole at Desert Inn Road and Topaz Street, where the waters were collected in various culverts and discharged onto the Lowe and Powers parcels.
Similarly, Desert Inn Road and its curbs and gutters were designed specifically to divert and channel waters, which would normally have drained into the large Flamingo Wash, onto the Lowe and Powers parcels. In addition, the County entered, without permission, onto the Lowe property, and built, without authorization, a concrete and rock berm.
The cumulative effect of these activities was to increase and accelerate the flow of waters through the ephemeral stream, to divert waters normally draining into the Flamingo Wash into the ephemeral stream, and to alter and divert the natural course of the ephemeral stream; the waters — as increased, accelerated, and diverted — cascaded over the entire length of the Powers parcel. By 1975, and continuing through the early part of 1976, the Powers parcel was deluged by a constant flow of water. Subsequent to the installation of a large drainpipe in the early part of 1976, the property was subjected to temporary, but frequent and inevitable, flooding. Once the Powers and Lowe parcels would become saturated, the waters entered the Wallace parcel as well. The collecting waters interfered seriously with repondents’ use and enjoyment of their land, and became a breeding ground for stench, mosquitoes, and disease.
Respondents filed this suit in the district court, based upon theories of inverse condemnation, nuisance, and trespass, seeking to be made whole for these injuries. After receiving evidence and testimony throughout an eleven day trial, reviewing a quantity of topographical maps, and making an on-site inspection of the relevant properties, the trial court, employing the reasonable use rule as applied to the drainage of surface waters, concluded that the County had unreasonably injured respondents’ lands; the court made an appropriate award of damages based on the nuisance and trespass claims. In addition, the court found that the County had taken the Powers parcel in its entirety: the property no longer had a practical use other than as a flood channel. 3 The court awarded just compensation. The court found as well that .247 acres of the Lowe *502 parcel, used by the County to construct a concrete berm, had been taken, and awarded just compensation. This appeal followed.
On appeal, the County advances two arguments requiring discussion: (1) the district court erred both in its adoption and application of the reasonable use rule; and (2) the County should be immune from liability for damages caused by what it terms “urbanization”. These, and the County’s remaining contentions, are without merit.
1. In adjudicating the competing rights and interests of respondent landowners and the County with regard to the drainage of surface waters, the district court, in the instant case, employed the reasonable use rule.
See
Armstrong v. Francis Corporation,
The question of which law to apply to the drainage of surface waters in this context, which entails a judgment concerning the proper allocation of costs incident to the
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transformation of rural or semi-rural areas into urban and suburban communities, is one of first impression in this state. Our prior cases, however, have enunciated three central principles: one, the law of water rights must be flexible, taking notice of the varying needs of various localities, Reno S. Works v. Stevenson,
The law concerning the drainage of surface waters must necessarily take into account a variety of factors: the nature of the land, soil, and terrain; the types of surface waters involved; the availability of natural drainways; the feasibility of artificial drainage systems; the uses to which the land has been and will be put; the benefit and the harm produced by the drainage; and a host of environmental and social concerns.
See generally
V Clark,
Waters and Water Rights,
§ 450.3
etseq.
(1972&Supp. 1978). The reasonable use rule allows for the careful consideration of each of these public and private concerns; growth and urbanization are not unduly restricted, but merely tempered with elements of order, planning and reasonableness. Butler v. Bruno,
We find as well that the economic costs incident to the expulsion of surface waters in the transformation of rural and semi-rural areas into urban and suburban communities should not be borne solely by adjoining landowners.
Armstrong,
Finally, we cannot agree with the County that the reasonable use rule is fatally unpredictable. Our review of the case law and literature reveals that the natural flow rule does not provide more predictable results than the reasonable use rule.
See Butler,
For the above reasons, we hold that the district court correctly adopted the reasonable use rule in adjudicating the competing rights of respondent landowners and the County with regard to the drainage of surface waters.
Applying the reasonable use rule to the instant case, the district court carefully considered all relevant factors. The court found that the County had not taken reasonable care to avoid the substantial injuries to respondents’ property, that the gravity of the harm caused by the drainage outweighed the benefits conferred by it, that the County could have avoided the harm by improving and complementing the natural system of drainage, and that the County could have utilized a pre-existing, alternative system of drainage, the Flamingo Wash, to avoid much of the injury. The County’s argument that these findings are not- supported by substantial evidence simply because the record contains conflicting evidence is not well taken. Tavel v. Olsson,
2. The County argues, relying on Baldwin v. City of Overland Park,
The district court found, and the record supports, that the injuries to respondents’ properties were caused by the County’s unreasonable acts, and not merely by the intangible and irresistible forces of urbanization. The County does not offer any reason why its actions in the instant case, found to be unreasonable by the district court, should be treated any differently
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than other examples of tortious conduct on the part of a governmental entity.
See
NRS 41.031(1);
compare
Crucil v. Carson City,
The County further argues, for the first time on appeal, that its actions in the instant case were discretionary, within the meaning of NRS 41.032(2), and therefore do not subject it to liability. This defense was neither pleaded nor raised below, and is not therefore properly before this Court. Hennessey v. Price,
Since the district court applied the correct rule of law, and its findings are supported by substantial evidence, the judgment is affirmed in all respects.
Notes
The respondents settled their dispute with these private parties, various land developers, prior to trial. The parties have stipulated that any judgment against the County shall be offset by a pro rata allocation of the settlement. The propriety of the settlement is not before this Court.
Additional party plaintiffs, the Rodrigueses, were awarded damages by the district court, but subsequent to trial, settled their dispute with the County. That aspect of the judgment is therefore no longer before this Court.
It has long been established that a taking occurs “where real estate is actually invaded by superinduced additions of water ... so as to effectually destroy or impair its usefulness,” Pumpelly v. Green Bay Company,
