[82 Ariz. 350] Harold R. Neubauer, City Atty., Gerald B. Hirsch and A. Alan Hanshaw, Asst. City Attys., Tucson, for appellant.
McCarty & Chandler, Tucson, for appellees.
Conner & Jones, Tucson, amicus curiae.
This is an action in damages for the negligent construction and maintenance of a culvert. It involves the same arroyo which has twice heretofore been before this court. City of Tucson v. O'Rielly Motor Co., 64 Ariz. 240, 168 P.2d 245; City of Tucson v. Apache Motors, 74 Ariz. 98, 245 P.2d 255, 260. Plaintiffs, appellees herein, after an extensive jury trial, recovered a judgment and the City of Tucson appeals.
Prior to 1925 there existed a natural arroyo running through the City of Tucson. Thereafter the city constructed a system of culverts which conducted underground the water flowing within the channel and covered over or filled in the arroyo. It is uncontradicted that the culverts were not of sufficient size to carry all of the water which from time to time drained off the watershed so that on occasions, in the years 1933, 1935, 1937, 1939, 1940, 1943, 1948 and 1953, they filled to capacity and the overflow spread out and ran down across the adjoining lands.
Since City of Tucson v. O'Rielly Motor Co., supra, it has been settled in this jurisdiction that if a municipal corporation constructs a culvert, it will be liable in damages for its inadequacy to carry away waters ordinarily coming into it, both the natural and normal flow and such abnormal and excessive flow as may reasonably be anticipated. In the following case of City of Tucson v. Apache Motors, we said that the city '* * * was required under the law to build culverts of sufficient size to adequately carry away all water accustomed to flow, or which may reasonably be anticipated to flow down such arroyo as a result of rains upon the watershed which it drained. * * *' The foregoing cases stated the principles of law relative to a determination of the issues then before the court, but in view of the issues presented in this controversy, we feel that it is necessary to enlarge somewhat on our previous views.
Ordinarily a municipal corporation has no duty to keep a stream flowing in a safe condition or to protect private property from overflow, but if it assumes to act, it is liable to the same extent as any other volunteer. It must act without negligence. Since the city has acted by covering over the arroyo and by providing culverts to carry underground the water which would be contained within the stream, its duty is to provide adequate culverts for that purpose, City of Tucson v. Apache Motors, supra. By diverting the waters underground through culverts, it has attempted [82 Ariz. 351] to contain whatever water is capable of being carried within the channel, both the natural and normal flow and such of the abnormal and excessive flow as might be reasonably anticipated at the time the culverts were installed, and is liable for damages proximately resulting from a failure to observe its duty in this regard.
Inherent in the view herein expressed are certain obvious limitations to the city's liability. We have heretofore defined flood waters as being those waters which escape from a watercourse in great volume and flow over adjoining lands in no regular channel, Southern Pacific Co. v. Proebstel, 61 Ariz. 412, 150 P.2d 81. Since the city, by covering over the arroyo and providing culverts has only attempted to control the flow of waters within the arroyo, it has assumed no responsibility for water which naturally leaves the channel and, therefore, is not liable for the damages caused by flood waters. The city's immunity from liability for damages caused by flood waters is absolute unless some other act or acts of the city caused or contributed to the overflow.
Moreover, the city is not liable for damages caused by the failure to handle water within the channel discharged into the arroyo by third persons in such increased volume as could not be reasonably anticipated at the time of the construction of the culverts. A prima facie case is established by those showing damages by water overflowing from the arroyo caused by the inadequacy of the culverts. In order for the city to escape liability the burden
is then on it to prove that the proximate cause of the overflow is the unanticipatable act or acts of third persons increasing the volume of water within the arroyo beyond the capacity of the culverts.
The city has questioned the refusal of the trial court to give a requested instruction which, in effect, told the jury that it was not liable for any damages occurring by reason of increased quantity of surface water draining into the arroyo because of artificial developments in areas outside the city and over which the city had no jurisdiction or control. We cannot examine into the claimed non-responsibility of the city under the peculiar circumstances of this case, since the city has failed to comply with Rule 51(a), Rules of Civil Procedure, 16 A.R.S., Section 21-1019 A.C.A.1939, requiring that exception be taken to the refusal to give requested instructions.
The city's first assignment of error relates to the failure of the trial court to direct a verdict in its favor because plaintiffs' damage was not proximately caused by the inadequacy of the culvert to carry away all the water capable of passing within the bed and banks of the arroyo. The evidence does not sustain the city's position on this point. A store building was erected [82 Ariz. 352] on Lots 9 and 10 of Block 44 in the City of Tucson. This building is eighty feet long and seventeen feet wide and fronts on Park Avenue to the west. The building is not within the channel of the arroyo, but its northeast corner abuts on the south bank. Plaintiffs were, on July 14, 1953, at the time of flooding complained of, tenants in this building. The arroyo itself drains generally from the east to the west and angles slightly in a northerly direction. At a point where the building touches the bank it is approximately ten feet deep, twenty to twenty-five feet wide at the bottom, with sloping banks at an angle of approximately forty-five degrees. The land immediately adjacent to the arroyo rises gradually from the banks both to the north and the south. The culvert starts on the east side of Park Avenue and runs westerly a distance of one-quarter of a mile. Across Park Avenue to the west, there has been constructed a service station. Seemingly the land there has been so filled that it is now at least one foot higher than the curb line of Park Avenue. The Murphey building is approximately level with the curb line and one foot above the top of the headwall of the culvert which, in turn, is approximately two feet above the top of the intake.
All the witnesses agree that on July 14, 1953, commencing at about the hour of 5:00 P.M. the following sequence of events occurred: That the culvert first filled with water to its capacity and then the water, unable to escape through the culvert, backed up, forming a pond, and finally escaped over the top of the headwall; that the water further ponded on Park Avenue until it reached a level at which it could ultimately escape to the west.
While many of the following facts are disputed, there is evidence from which the jury could have found facts favorable to plaintiffs, as follows: That the capacity of the culvert was 2,700 cubic feet per second; that the capacity of the arroyo at the intake of the culvert was 3,920 cubic feet per second; that the peak flow down the arroyo four blocks immediately to the east was 3,140 feet per second. From this the jury could have inferred not only that the arroyo was capable of draining and containing all the surface water which emptied into it prior to its entrance into the culvert, but that the culvert was incapable of carrying the water draining within the arroyo at the point of intake.
The city argues that the proximate cause of the plaintiffs' damages was not the inadequacy of the culverts, but the additional fact that the service station across Park Avenue, being higher than the headwall of the culvert, formed a barricade which caused the water to pond upon the plaintiffs' property. We cannot agree with this argument. The negligence of the city is constant from day to day and moment to moment from the time of the establishment[82 Ariz. 353]
of the inadequate culverts, and its duty to provide adequate culverts is a continuing one to be exercised with due regard to the conditions affecting the flow of water to be accommodated. The efficient cause of the plaintiffs' damage is the city's original negligence. At most, the service station across the street forming a further barricade to the water was a concurring cause for ...