Title: Milwaukee Metropolitan Sewerage District v. City of Milwaukee
Citation: 2005 WI 8
Docket Number: 2002AP002961
State: Wisconsin
Issuer: Wisconsin Supreme Court
Date: January 27, 2005

2005 WI 8 
 
 
 
SUPREME COURT OF WISCONSIN 
 
 
 
 
 
CASE NO.: 
02-2961 
COMPLETE TITLE: 
 
 
Milwaukee Metropolitan Sewerage District,  
          Plaintiff-Appellant, 
 
     v. 
 
City of Milwaukee,  
          Defendant-Respondent-Petitioner. 
 
 
 
 
REVIEW OF A DECISION OF THE COURT OF APPEALS 
2003 WI App 209 
Reported at:  267 Wis. 2d 688, 671 N.W.2d 346 
(Ct. App. 2003-Published) 
 
 
OPINION FILED: 
January 27, 2005 
SUBMITTED ON BRIEFS: 
        
ORAL ARGUMENT: 
September 10, 2004 
 
 
SOURCE OF APPEAL: 
 
 
COURT: 
Circuit   
 
COUNTY: 
Milwaukee   
 
JUDGE: 
Mel Flanagan   
 
 
 
JUSTICES: 
 
 
CONCURRED: 
PROSSER, J., concurs (opinion filed).   
 
DISSENTED: 
        
 
NOT PARTICIPATING:         
 
 
 
ATTORNEYS: 
 
For the defendant-respondent-petitioner there were briefs 
by Grant F. Langley, Susan E. Lappen, Rudolph M. Konrad, and 
Anne Berleman Kearney, Milwaukee, and oral argument by Rudolph 
M. Konrad. 
 
For the plaintiff-appellant there was a brief by Michael J. 
McCabe and James H. Petersen, Milwaukee, and oral argument by 
James H. Petersen. 
 
An amicus curiae brief was filed by Claire Silverman, 
Madison, on behalf of the League of Wisconsin Municipalities. 
 
2005 WI 8 
NOTICE 
This opinion is subject to further 
editing and modification.  The final 
version will appear in the bound 
volume of the official reports.   
No.  02-2961  
(L.C. No. 
00 CV 10373) 
STATE OF WISCONSIN  
 
 
   : 
IN SUPREME COURT 
 
 
Milwaukee Metropolitan Sewerage District,  
 
 
          Plaintiff-Appellant, 
 
     v. 
 
City of Milwaukee,  
 
          Defendant-Respondent-Petitioner. 
 
FILED 
 
JAN 27, 2005 
 
Cornelia G. Clark 
Clerk of Supreme Court 
 
 
 
 
 
REVIEW of a decision of the Court of Appeals.  Affirmed.   
 
 
¶1 
JON P. WILCOX, J.   The City of Milwaukee (the City) 
appeals from a published court of appeals decision, Milwaukee 
Metropolitan Sewerage District v. City of Milwaukee, 2003 WI App 
209, 267 Wis. 2d 688, 671 N.W.2d 346, reversing a Milwaukee 
County Circuit Court order, Mel Flanagan, Judge, that granted 
the City's motion for summary judgment.   
I. 
PROCEDURAL POSTURE 
¶2 
On December 13, 2000, Milwaukee Metropolitan Sewerage 
District (MMSD) filed a complaint in Milwaukee County Circuit 
Court to recover sums related to the repair and replacement of 
No. 
02-2961   
 
2 
 
its metropolitan interceptor sewer (MIS) at North 40th Street 
and West Bluemound Road in Milwaukee, which allegedly collapsed 
on December 9, 1999, due to the rupture and collapse of the 
City's nearby water main.   
¶3 
MMSD's complaint alleged both negligence and nuisance.  
The complaint averred, relative to the negligence claim, that 
the City "did not properly monitor the volume of water through 
the pipeline, did not properly inspect the pipeline, did not 
notice the unusual water flows in the vicinity, and did not 
properly repair/replace the City's water main in the vicinity of 
North 40th Street and West Bluemound Road."  With regard to the 
alleged nuisance, MMSD averred:  "The City has, upon information 
and belief, permitted a nuisance condition to exist, to wit:  
the existence of broken water main, which nuisance caused the 
collapse of the District's MIS."  MMSD also stated a cause of 
action for unjust enrichment, arising from its repair of the 
City's water main.   
¶4 
Following a stipulation of the parties, on May 8, 
2002, the circuit court dismissed MMSD's claim for unjust 
enrichment.  Shortly thereafter, the City filed a motion for 
summary judgment, seeking a dismissal of MMSD's remaining 
claims.  In its motion, the City argued:  1) It had no notice of 
any alleged defect regarding the water main; 2) It was not 
negligent because it did not breach any duty it owed to MMSD and 
did not cause MMSD's damages; 3) It was entitled to statutory 
immunity relative to both the nuisance and negligence claim; and 
4) There was no nuisance.  After briefing, a hearing was held on 
No. 
02-2961   
 
3 
 
the motion in which the circuit court ruled:  1) The City did 
not have notice regarding the alleged defective condition, and 
such lack of notice was a viable defense to both the negligence 
and nuisance claims; 2) The City was entitled to immunity from 
the 
negligence 
and 
nuisance 
claims 
based 
on 
Wis. Stat. § 893.80(4)(1999-2000)1 and related case law; and 3) 
MMSD's theory of res ipsa loquitur was not supported by the 
undisputed facts.  Thus, on September 19, 2002, the circuit 
court entered judgment in favor of the City, thereby dismissing 
MMSD's remaining claims.  Following a dispute concerning 
photocopying costs, the circuit court entered an amended 
judgment on October 22, 2002.  MMSD appealed both the judgment 
and amended judgment.   
¶5 
The court of appeals reversed the circuit court, 
concluding notice was not required to prevail on a claim of 
private 
nuisance. 
 
Milwaukee 
Metro. 
Sewerage 
Dist., 
267 
Wis. 2d 688, ¶¶14-16.  The court of appeals stated that MMSD was 
alleging that the City created a nuisance.  Id., ¶11.  The court 
of appeals also concluded that the City was not entitled to 
immunity from a nuisance suit based on Winchell v. City of 
Waukesha, 110 Wis. 101, 109, 85 N.W. 668 (1901), and several 
court of appeals decisions relying on Winchell.  Milwaukee 
Metro. Sewerage Dist., 267 Wis. 2d 688, ¶¶18-21.  The court of 
appeals also concluded that under Wis. Stat. § 893.80(4), "while 
                                                 
1 All subsequent references to the Wisconsin Statutes are to 
the 1999-2000 version unless otherwise noted.   
No. 
02-2961   
 
4 
 
a cause of action alleging negligence is immunized, a nuisance 
created by negligent conduct is not protected . . . ."  Id., 
¶22.  Also, the court of appeals rejected the City's argument 
that public policy should limit liability.  Id., ¶23.  Further, 
the court of appeals concluded that the circuit court's ruling 
regarding res ipsa loquitur was premature, although the court of 
appeals ultimately left it to the circuit court's discretion 
whether to give a jury instruction on the doctrine.  Id., ¶¶26-
28.  Finally, the court of appeals ruled that the circuit court 
erred in awarding photocopying costs to the City.  Id., ¶29.   
¶6 
For the reasons discussed below, we affirm the 
ultimate decision of the court of appeals that summary judgment 
should not have been granted, although we do so based on an 
entirely different rationale.  We hold that in order to 
establish a prima facie case for liability for a nuisance, there 
must be proof of the nuisance, proof of the underlying tortious 
conduct giving rise to the nuisance, and proof that the tortious 
conduct was the legal cause of the nuisance.  The alleged 
nuisance in this case is the City's interference with MMSD's 
property interest in its sewer.   
¶7 
We conclude that under the law governing liability for 
nuisance based on intentional conduct, the pleadings and record 
do not support any claim that the City intentionally created a 
nuisance.  We conclude that the only actionable tortious act 
giving rise to the nuisance in this case is the City's alleged 
negligence in failing to repair its leaky water main before it 
burst.  We reaffirm our existing case law that when a nuisance 
No. 
02-2961   
 
5 
 
is predicated on negligence, all the usual rules and defenses 
applicable to negligence claims apply.  Thus, when a nuisance is 
predicated on a negligent failure to act, there must be proof 
that the defendant's conduct constituted actionable negligence, 
including proof of notice, regardless of whether the alleged 
nuisance is public or private.  
¶8 
Moreover, 
we 
hold 
that 
under 
§ 893.80(4), 
and 
Wisconsin's immunity jurisprudence since Holytz v. City of 
Milwaukee, 17 Wis. 2d 26, 115 N.W.2d 618 (1962), a municipality 
may be immune from nuisance suits depending on the nature of the 
tortious acts giving rise to the nuisance.  A municipality is 
immune from suit for nuisance if the nuisance is predicated on 
negligent acts that are discretionary in nature.  A municipality 
does not enjoy immunity from suit for nuisance when the 
underlying tortious conduct is negligence and the negligence is 
comprised of acts performed pursuant to a ministerial duty.   
¶9 
Decisions 
concerning 
the 
adoption, 
design, 
and 
implementation of a public works system are discretionary, 
legislative decisions for which a municipality enjoys immunity.  
Thus, the City is immune from suit relating to its decisions 
regarding the adoption of a waterworks system, the selection of 
the specific type of pipe, the placement of the pipe in the 
ground, and the continued existence of such pipe.  In contrast, 
the City may be liable for its negligence in failing to repair 
the leaky water main.  However, since there exists a material 
issue of fact as to whether the City had notice of the leaking 
water main, we cannot determine whether the City was under a 
No. 
02-2961   
 
6 
 
ministerial duty to repair its water main prior to the break.  
Thus, we cannot determine whether the City is immune under 
§ 893.80(4) from liability predicated upon a negligent failure 
to repair the water main before it burst.   
¶10 Finally, viewing the summary judgment materials in a 
light most favorable to MMSD, we conclude that there are at 
least two disputed issues of material fact.  In addition to the 
disputed issue of fact regarding whether the City had notice of 
the leaking water main prior to the break, there exists a 
disputed issue of fact as to what caused MMSD's sewer to 
collapse.  Therefore, we affirm the decision of the court of 
appeals, reversing the circuit court's grant of summary judgment 
in favor of the City.   
II. FACTUAL BACKGROUND  
¶11 The following is a brief summary of the facts giving 
rise to the complaint.  Further facts will be set forth later in 
the opinion.  On December 9, 1999, at approximately 4:45 a.m., a 
City of Milwaukee Waterworks employee responded to a call that 
water was entering the basement of a home near 40th Street and 
Bluemound Road.  Shortly thereafter, City employees turned off 
two main gate valves in order to stop the flow of water.  A City 
employee testified that the water main break was severe and that 
it caused substantial damage to the roadway above the water 
main.  However, the water was not surfacing on the street.  It 
was later discovered that a 12-to-15 foot section of the water 
main had completely snapped off and fell into the MIS.  Another 
City employee testified that the MIS was sucking water and 
No. 
02-2961   
 
7 
 
debris down into it, creating a large sloping cone-shaped hole 
in the ground.  The broken water main was taken offline at 5:59 
a.m. on December 9, 1999, and, following the installation of a 
gate valve, service was restored at 9:33 p.m.   
¶12 The water main located at 40th and Bluemound was made 
of 8-inch diameter pit cast iron pipe, which was installed in 
1926.  The water main was buried approximately 12 feet into the 
ground.  The MIS, also known as the Menomonee Special Sewer, was 
constructed out of brick in the 1880s.  It was 60 inches in 
diameter and was located below the City's water main.  The MIS 
was buried approximately 23 feet into the ground and carried 
waste flowage from Miller Brewing Company.  The MIS was not 
originally built as a sanitary sewer; it was originally designed 
as a "flushing line" to carry river water.   
¶13 Mark Scheller, the Water Mains Design Engineer for the 
Milwaukee 
Waterworks, 
testified 
that 
the 
City 
operates 
approximately 1300 miles of pit cast iron pipe, the majority of 
which was laid before 1963.2  Pit cast iron was the industry 
                                                 
2 Mr. Scheller stated in his affidavit that the majority of 
water main breaks occur in cast iron pipe that was laid after 
World War II.  These mains were constructed from centrifugally 
cast iron pipe ("spun pipe"), and were installed between 1945 
and 1963.   
No. 
02-2961   
 
8 
 
standard prior to 1945.3  Since 1963, the City has utilized 
ductile iron pipe.  In addition, the City currently utilizes 
modern industry practices such as rubber mechanical joints, 
limestone backfill, and polyethylene wrap to reduce the risk of 
corrosion in the pipes.   
¶14 Mr. Scheller testified that the City does not have a 
systematic plan for replacing water mains.  Rather, water mains 
are replaced based on their break history, water quality, and 
other variables.  The City records and tracks data on water main 
breaks and maintains a searchable database of such information.  
The City is able to isolate a section of a main and rank it 
based on its break history.  The Waterworks Department replaces 
as many mains as it can, given the funds allocated to it every 
year.  Thus, when a water main breaks, the City replaces the 
break area and not the entire service line.  The estimated cost 
of replacing each mile of cast iron main is $1,000,000.  Given 
the City's 1300 miles of cast iron pipe, the cost to replace the 
entire system is estimated at $1,300,000,000.  Because of the 
high cost of replacing an entire water main, such mains are 
replaced only when they have suffered a sufficient number of 
breaks and attendant problems.  
                                                 
3 In his affidavit, Mr. Scheller relayed a brief history of 
the use of cast iron pipes.  Mr. Scheller stated that cast iron 
pipe was first installed in Germany in 1455 at the Dillenburg 
Castle. 
 
Apparently, 
Louis 
XIV 
of 
France 
ordered 
the 
construction of a 15-mile cast iron pipeline in France in 1664 
that is still in service today.  Several cities in the United 
States have cast iron water mains that have been in service for 
at least 150 years.   
No. 
02-2961   
 
9 
 
III. STANDARD OF REVIEW 
¶15 This court reviews a circuit court's grant of summary 
judgment independently, but we apply the same methodology as the 
circuit court.  Smaxwell v. Bayard, 2004 WI 101, ¶12, 274 
Wis. 2d 278, 
682 
N.W.2d 923. 
 
Pursuant 
to 
Wis. Stat. § 802.08(2), summary judgment "shall be rendered if 
the pleadings, depositions, answers to interrogatories, and 
admissions on file, together with the affidavits, if any, show 
that there is no genuine issue as to any material fact and that 
the moving party is entitled to a judgment as a matter of law."  
Thus, "[s]ummary judgment should not be granted, 'unless the 
facts presented conclusively show that the plaintiff's action 
has no merit and cannot be maintained.'"  Smaxwell, 274 
Wis. 2d 278, ¶12 (quoting Goelz v. City of Milwaukee, 10 
Wis. 2d 491, 495, 103 N.W.2d 551 (1960)).   
¶16 In addition, "[w]e view the summary judgment materials 
in the light most favorable to the nonmoving party."  Id.  If 
there is no dispute concerning the material facts, this court is 
presented solely with a question of law.  Id.  Whether there is 
a legal basis for a nuisance claim is a question of law subject 
to de novo review.  Stunkel v. Price Elec. Coop., 229 
Wis. 2d 664, 668, 559 N.W.2d 919 (Ct. App. 1999).   
IV. ANALYSIS 
¶17 The City argues that contrary to the court of appeals' 
decision, this case does not involve the creation of a nuisance.  
The City asserts that its water main was not a nuisance when 
installed and that an old water pipe does not constitute a 
No. 
02-2961   
 
10 
 
nuisance so long as the useful life of the pipe has not expired.  
The City explains that MMSD's claim is one for maintenance of a 
nuisance.  The City notes that in its complaint, MMSD alleged 
that the City "permitted a nuisance condition to exist."   
¶18 The City further argues that in order to succeed on a 
claim for maintenance of a nuisance, MMSD must prove causation 
and that it cannot do so given the record in this case.  In 
addition, the City asserts that the court of appeals incorrectly 
concluded that it was not entitled to raise a defense of notice.  
According to the City, notice is an essential part of a claim 
for maintenance of a nuisance.  The City notes that MMSD has 
stipulated that the City did not have actual notice of any leak 
or defect in its pipe.  Further, the City states that there is 
no evidence that it had constructive notice of such a condition.   
¶19 Moreover, the City argues that the court of appeals 
incorrectly concluded that it was not entitled to discretionary 
immunity under case law and § 893.80(4).  The City asserts that 
it is entitled to immunity for any decisions regarding the 
design and placement of the pipe.  In addition, it maintains 
that it has immunity for decisions relating to the repair and 
replacement of water mains because updating the water main 
system is a legislative act.  Finally, the City asserts that it 
should be relieved of any liability based on public policy 
grounds.   
¶20 In contrast, MMSD argues that the City intentionally 
created a nuisance by failing to inspect its water mains and 
adopting a system whereby it merely repairs obsolete pipes that 
No. 
02-2961   
 
11 
 
have a history of breaking.  MMSD argues that the City 
intentionally continues to use inferior quality water mains 
until they can no longer be repaired economically.  MMSD states 
that there is a material issue of fact as to causation.  MMSD 
also asserts that notice is not a prerequisite to liability when 
a nuisance claim involves the invasion of property interests.  
MMSD further maintains that negligence is not a prerequisite to 
liability in a private nuisance case because liability is based 
on the violation of an absolute duty.   
¶21 MMSD argues that even if notice were a prerequisite to 
liability, it has established a prima facie case for notice.  
MMSD asserts that the City once utilized a system of pressure 
testing water mains that it has since abandoned.  In addition, 
MMSD notes that the water main in question has a history of 
breaking, as it had previously ruptured in 1988 and 1989.  
Further, MMSD emphasizes that the record indicates that a 
construction project occurred in 1992-93 directly above the 
water main in question and that City documents indicate that due 
to some construction problems that may have damaged the water 
main, the City was to inspect the water main but never did so.   
¶22 Moreover, MMSD contends that by the 1970s the City was 
aware that the water main in question was constructed with 
inferior material and the City did nothing to alleviate the risk 
that the main might break.  MMSD also provides a number of 
statistics relating to the break rate of the City's water mains 
and the rate of water loss from the system and contends the City 
No. 
02-2961   
 
12 
 
was aware that a break was almost certain to occur unless it 
replaced its old cast iron pipes.   
¶23 Furthermore, MMSD argues that the court of appeals 
correctly determined that the City was not entitled to immunity 
under either the common law or § 893.80(4).  MMSD contends that 
the City had a ministerial duty to maintain its water mains so 
that they did not cause damage to other property.  MMSD argues 
that it is well-established law that municipal immunity does not 
extend to claims for nuisance.  Finally, MMSD argues that public 
policy supports holding the City liable for nuisances that 
invade the property interests of others. 
A. 
Nuisance Defined:  Private and Public Nuisance 
¶24 The first step in any nuisance analysis is to 
determine whether a nuisance actually exists.  Physicians Plus 
Ins. Corp. v. Midwest Mut. Ins. Co., 2002 WI 80, ¶27, 254 
Wis. 2d 77, 646 N.W.2d 777.  It has been said that "[t]here is 
perhaps no more impenetrable jungle in the entire law than that 
which surrounds the word 'nuisance.'  It has meant all things to 
all people, and has been applied indiscriminately to everything 
from an alarming advertisement to a cockroach baked in a pie."  
W. Page Keeton et al., Prosser and  Keeton on Torts § 86, at 616 
(5th ed. Lawyers ed. 1984)[hereinafter Prosser and  Keeton on 
Torts].  However, the term "nuisance" generally refers to the 
invasion of either an interest in the use and enjoyment of land 
or a common public right.  See id., § 86, at 618; Restatement 
(Second) of Torts, Introductory Note to §§ 821-49 (1977).  This 
court has defined a nuisance as follows:  "A nuisance is a 
No. 
02-2961   
 
13 
 
condition or activity which unduly interferes with the use of 
land or of a public place."  Physicians Plus, 254 Wis. 2d 77, 
¶21.   
¶25 At the outset, it is imperative to distinguish between 
a nuisance and liability for a nuisance, as it is possible to 
have a nuisance and yet no liability.  A nuisance is nothing 
more than a particular type of harm suffered; liability depends 
upon the existence of underlying tortious acts that cause the 
harm.  The Restatement (Second) of Torts illustrates this point:   
[F]or a nuisance to exist there must be harm to 
another or the invasion of an interest, but there need 
not be liability for it.  If the conduct of the 
defendant is not of a kind that subjects him to 
liability . . . the nuisance exists, but he is not 
liable for it.   
Restatement (Second) of Torts § 821A cmt. c (emphasis added).4  
                                                 
4 Wisconsin has explicitly adopted the definition of private 
nuisance found in the Restatement (Second) of Torts, § 821.  
Vogel v. Grant-Lafayette Elec. Coop., 201 Wis. 2d 416, 423, 548 
N.W.2d 829 (1996); Prah v. Maretti, 108 Wis. 2d 223, 231, 321 
N.W.2d 182 (1982).  Wisconsin's definition of public nuisance 
also comports with the Restatement (Second) of Torts § 821B.  
Physicians Plus Ins. Corp. v. Midwest Mut. Ins. Co., 2002 WI 80, 
¶21 n.15, 254 Wis. 2d 77, 646 N.W.2d 777.  In addition, 
Wisconsin has adopted the Restatement (Second) of Torts § 822.  
Vogel, 201 Wis. 2d at 428; CEW Mgmt. Corp. v. First Fed. Sav. & 
Loan Ass'n, 88 Wis. 2d 631, 633, 277 N.W.2d 766 (1979); Stunkel 
v. Price Elec. Coop., 229 Wis. 2d 664, 668, 599 N.W.2d 919 (Ct. 
App. 1999); Fortier v. Flambeau Plastics Co., 164 Wis. 2d 639, 
676, 476 N.W.2d 593 (Ct. App. 1991); Wis JI-Civil 1920 Comment 
(2004).  This court has also previously relied on other sections 
of the Restatement governing nuisances.  See, e.g., Vogel, 201 
Wis. 2d at 
423-32 
(applying 
Restatement 
(Second) 
of 
Torts 
§§ 825, 840).  
No. 
02-2961   
 
14 
 
¶26 Much of the confusion in nuisance law results from a 
"[f]ailure to recognize that . . . nuisance has reference to the 
interest invaded and not to the type of conduct that subjects 
the actor to liability."  Restatement (Second) of Torts § 822 
cmt. b.  Thus, a cause of action in nuisance is predicated upon 
a particular type of injurious consequence, not the wrongful 
behavior causing the harm.   Physicians Plus, 254 Wis. 2d 77, 
¶22 n.18.  While it is necessary to prove the underlying 
tortious conduct before liability may attach for a nuisance, it 
is incorrect to speak of nuisance "as itself a type of 
liability-forming conduct . . . ."  Restatement (Second) of 
Torts § 822 cmt. c.  As such, the first step in a nuisance 
analysis is proof of the particular harm that defines a 
nuisance——the interference with a private interest in the use 
and enjoyment of land or with a public right.  See Physicians 
Plus, 254 Wis. 2d 77, ¶¶27-28.  
¶27 Nuisances come in two varieties, public and private, 
which are distinguished by the nature of the interest invaded.  
"The essence of a private nuisance is an interference with the 
use and enjoyment of land."  Prosser and Keeton on Torts § 87, 
at 619.  See also Krueger v. Mitchell, 112 Wis. 2d 88, 103, 332 
N.W.2d 733 
(1983); 
Restatement 
(Second) 
of 
Torts 
§ 821D; 
Restatement (Second) of Torts § 822 cmt. c.  Since a private 
nuisance is "broadly defined to include any disturbance of the 
enjoyment of property[,]"  Prah v. Maretti, 108 Wis. 2d 223, 
232, 321 N.W.2d 182 (1982), an action to recover damages for a 
private nuisance may be brought by those who "have property 
No. 
02-2961   
 
15 
 
rights and privileges in respect to the use and enjoyment of the 
land affected," including possessors of the land and owners of 
easements.  Restatement (Second) of Torts § 821E.   
¶28 In contrast, "[a] public nuisance is a condition or 
activity which substantially or unduly interferes with the use 
of a public place or with the activities of an entire 
community."  Physicians Plus, 254 Wis. 2d 77, ¶21.  In other 
words, "[a] public nuisance is an unreasonable interference with 
a right common to the general public."  Restatement (Second) of 
Torts § 821B.  See also Prosser and Keeton on Torts § 86, at 618 
(accord).  Therefore, the interest involved in a public nuisance 
is broader than that in a private nuisance because "a public 
nuisance does not necessarily involve interference with use and 
enjoyment of land."  Restatement (Second) of Torts § 821B cmt. 
h. 
¶29 It should be stressed that the distinction between a 
private and public nuisance is "not the number of persons 
injured but the character of the injury and of the right 
impinged upon."  Costas v. City of Fond du Lac, 24 Wis. 2d 409, 
414, 129 N.W.2d 217 (1964)(emphasis added).  See also Physicians 
Plus, 254 Wis. 2d 77, ¶21; Schiro v. Oriental Realty Co., 272 
Wis. 537, 546, 76 N.W.2d 355 (1956).  "Conduct does not become a 
public nuisance merely because it interferes with the use and 
enjoyment of land by a large number of persons.  There must be 
some interference with a public right."  Restatement (Second) of 
Torts § 821B cmt. g.  Since the term public nuisance refers to a 
broader set of invasions than private nuisance, "[a] nuisance 
No. 
02-2961   
 
16 
 
may be both public and private in character. . . . A public 
nuisance which causes a particular injury to an individual 
different in kind and degree from that suffered by the public 
constitutes a private nuisance."  Costas, 24 Wis. 2d  at 413-14.  
See also Restatement (Second) of Torts § 821B cmt. h (accord). 
¶30 In sum, a nuisance exists if there is a condition or 
activity that unduly interferes with the private use and 
enjoyment of land or a public right.  If the interest invaded is 
the private use and enjoyment of land, then the nuisance is 
considered a private nuisance.  Conversely, if the condition or 
activity interferes with a public right or the use and enjoyment 
of public space, the nuisance is termed a public nuisance.  
Physicians Plus, 254 Wis. 2d 77, ¶21 n.14, ¶28; Schiro, 272 
Wis. at 546.  While there initially was some confusion over 
whether the nuisance in this case was public or private, this 
confusion was due to a typographical error in one of the briefs 
and the parties agreed at oral argument that the nuisance 
alleged here 
is a private 
nuisance, 
as 
it 
involves an 
interference with MMSD's property interest in its sewer.   
¶31 We emphasize that the alleged nuisance in this case is 
the invasion of MMSD's property interest in its sewer line.  The 
fact that the City's water main system as a whole may be 
comprised of older pipes, some of which have a history of 
leaking and breaking, is not germane to the issue of whether a 
nuisance exists in this case.  The actionable nuisance here is 
not the City's water main "system"; rather, the actionable 
nuisance is the City's interference with MMSD's sewer, which was 
No. 
02-2961   
 
17 
 
allegedly caused by a leaky water main located at 40th and 
Bluemound.  Having set forth the definition of nuisance and 
determined that this case involves a private nuisance, we next 
examine the elements necessary to hold an actor liable for a 
private nuisance.   
B. 
Elements of a Private Nuisance Claim 
¶32 The 
Restatement 
(Second) 
of 
Torts 
provides 
the 
following elements for liability for a private nuisance:  
One is subject to liability for a private nuisance if, 
but only if, his conduct is a legal cause of an 
invasion of another's interest in the private use and 
enjoyment of land, and the invasion is either  
(a) intentional and unreasonable, or 
(b) unintentional and otherwise actionable under the 
rules 
controlling 
liability 
for 
negligent . . . conduct . . . .    
Restatement (Second) of Torts § 822.5  See also Wis JI-Civil 
1920.  Therefore, after it is established that a nuisance 
exists, the next step in a nuisance analysis is determining 
whether there is any liability-forming conduct.  Proof of the 
underlying tortious conduct is an essential element in a 
nuisance analysis.  Stunkel, 229 Wis. 2d at 671 ("[W]e conclude 
that no claim for private nuisance may be made without the 
underlying prerequisite conduct being proved.").  As we stated 
in Physicians Plus:  "[L]iability is 'founded on the wrongful 
                                                 
5 The Restatement also allows for liability based upon the 
rules 
governing 
reckless 
conduct 
or 
abnormally 
dangerous 
conditions.  Restatement (Second) of Torts § 822.  Neither of 
these two types of conduct are present in the case at bar.   
No. 
02-2961   
 
18 
 
act 
in . . . creating 
or 
maintaining 
[the 
nuisance].'"  
Physicians Plus, 254 Wis. 2d 77, ¶27 (quoting Brown v. Milwaukee 
Terminal Ry. Co., 199 Wis. 575, 589, 227 N.W. 385 (1929)).   
¶33 Liability for a nuisance may be based upon either 
intentional 
or 
negligent 
conduct. 
 
Physicians 
Plus, 
254 
Wis. 2d 77, ¶20; Schiro, 272 Wis. at 546; Restatement (Second) 
of Torts § 822.  Much of the confusion in this case results from 
the parties' dispute over whether the City "created a nuisance" 
or "maintained a nuisance" and the differing standards of 
liability for each classification.  In Brown, 199 Wis. at 589, 
this court noted that one may be liable for nuisance for either 
creating or maintaining the nuisance.  In Brown, we stated that 
"[i]n those cases where the nuisance is created by the 
defendant, no question of negligence or want of ordinary care is 
involved."  Id. at 589.  As we explained in Brown, this rule 
applies in cases such as "a tannery or a slaughter-house in the 
midst of a residential area, where the mere act of using the 
plant creates the nuisance."  Id.  In these cases, liability 
"'does not rest on the degree of care used, for that presents a 
question of negligence, but on the degree of danger existing 
even with the best of care.'"  Id. (quoted source omitted).  In 
cases where the defendant is "engaged in intentional conduct 
that 
severely 
affect[s] 
the 
neighbor's 
peaceful 
use 
and 
enjoyment of their property[,]" Stunkel, 229 Wis. 2d at 670, 
"[a] finding of intentional but unreasonable conduct, even 
though lawful, is sufficient to meet the requirements of the 
Restatement under subsection (a)."  Id. 
No. 
02-2961   
 
19 
 
¶34 In contrast, Brown noted a "class of cases in which 
the acts or conduct of the defendant do not necessarily cause 
damage to others." Brown, 199 Wis. at 589.  Such cases involve 
changes to otherwise benign objects that develop over time and 
become harmful, through no fault of the owner of the object.  
Id. at 589-90.  In these cases, liability is predicated upon the 
defendant's failure to remove the harmful condition after he has 
notice of its existence.  Id. at 590. 
¶35 The Restatement (Second) of Torts § 824, while not 
using the terms "creating" or "maintaining," provides that an 
individual is liable for an "act" or "failure to act" that 
results in a nuisance.  Restatement (Second) of Torts § 824.  
Consistent with Brown, the Restatement (Second) of Torts 
provides that when liability is predicated on a "failure to 
act," there must be proof that the actor was "under a duty to 
take positive action to prevent or abate the interference with 
the public interest or the invasion of the private interest."  
Id.  Thus, liability for a nuisance is dependent upon the type 
of underlying tortious conduct that causes the nuisance, be it 
an act or failure to act in circumstances where there is a duty 
to act.  CEW Mgmt. Corp. v. First Fed. Sav. & Loan Ass'n, 88 
Wis. 2d 631, 634-36, 277 N.W.2d 766 (1979)("In any tort, the 
tortfeasor's liability follows from either his act or a failure 
to act when he has a duty to do so.").   
¶36 Therefore, labeling a case as one involving the 
"creation" of a nuisance or the "maintenance" of a nuisance 
before one has examined whether the tortious acts causing the 
No. 
02-2961   
 
20 
 
nuisance were negligent or intentional begs the question.  See 
Schiro, 272 Wis. at 546-47 (noting that liability for nuisance 
is 
determined 
by 
the 
rules 
governing 
liability 
for 
the 
underlying tortious conduct and not the label the plaintiff 
places on a cause of action).  As such, in order to determine 
whether one is liable for a nuisance, it must be determined 
whether there is any underlying liability-forming tortious 
conduct and whether such conduct is intentional or negligent.  
Only then may the case be classified as one involving the 
"creation of a nuisance" or the "maintenance of a nuisance."   
¶37 We now examine whether the City may be liable for the 
alleged nuisance based on the rules governing liability for 
either intentional or negligent conduct.6  An interference with 
another's interest in the use and enjoyment of land is deemed to 
be "intentional" if the actor "(a) acts for the purpose of 
causing 
it, 
or 
(b) 
knows 
that 
it 
is 
resulting 
or 
is 
substantially certain to result from his conduct."  Restatement 
(Second) of Torts § 825.7  Thus, a nuisance is based on 
intentional conduct when the defendant, through ill will or 
malice, intends to cause the interference or if the defendant, 
                                                 
6 In addition to its numerous arguments regarding the City's 
intentional conduct in its brief, Petr's Br. at 17-20, 23-24, at 
oral argument, counsel for MMSD specifically argued that should 
the case be remanded, it was free to proceed either on a theory 
of intentional or negligent nuisance.  Thus, it is necessary to 
address the prerequisites for liability for both an intentional 
nuisance and a negligence-based nuisance.    
7 This court has previously applied Restatement (Second) of 
Torts § 825.  Vogel, 201 Wis. 2d at 430-31.     
No. 
02-2961   
 
21 
 
without any desire to cause harm, nonetheless has knowledge that 
his 
otherwise 
legal 
enterprise 
is 
causing 
harm 
or 
is 
substantially certain to cause the invasion at issue.  Vogel v. 
Grant-Lafayette 
Elec. Coop., 
201 
Wis. 2d 416, 
430-31, 548 
N.W.2d 829 (1996).   
¶38 It is important to clarify that when a nuisance is 
alleged to fall under the second category of intentional 
conduct, the "knowledge" requirement refers to knowledge that 
the condition or activity is causing harm to another's interest 
in the use and enjoyment of land.  Vogel, 201 Wis. 2d at 431 
(noting that "the invasion under the Restatement must be in 
another's interest in the use and enjoyment of land, not merely 
an invasion in the land").  Thus, in Vogel, a case involving 
stray voltage alleged to have damaged a farmer's cows, this 
court stated that it was not sufficient that the defendant knew 
that some stray voltage invaded the farmer's land; rather, proof 
was required that the defendant knew that unreasonable levels of 
the stray voltage were causing harm to the plaintiff's cows.  
Id. at 432-33.   
¶39 Here, there is absolutely no evidence, nor does MMSD 
allege, that the City installed the water main in 1926 for the 
purpose of interfering with MMSD's use and enjoyment of its  
easement 
or 
with 
knowledge 
that 
such 
interference 
was 
substantially certain to occur.8  In addition, there is no 
                                                 
8 "It is the knowledge that the actor has at the time he 
acts or fails to act that determines whether the invasion 
resulting from his conduct is intentional or unintentional."  
Restatement (Second) of Torts § 825 cmt. c. 
No. 
02-2961   
 
22 
 
evidence that the City failed to inspect its pipes for the 
purposes of interfering with MMSD's sewer.  Also, because MMSD 
has conceded that the City had no actual knowledge of any leak 
at the point where MMSD's interceptor sewer was located, there 
is no evidence that the City was actually aware that MMSD's 
sewer was being damaged or was substantially certain to be 
damaged by it water main.  While we discuss the issue of 
constructive notice later in the opinion, for purposes of the 
present discussion, "[i]t is not enough to make an invasion 
intentional that the actor realizes or should realize that his 
conduct involves a serious risk or likelihood of causing the 
invasion."  Restatement (Second) of Torts § 825 cmt. c.  Rather, 
in order for an invasion to be intentional, the actor "must 
either act for the purpose of causing it or know that it is 
resulting or is substantially certain to result from his 
conduct."  Id.   
¶40 In 
sum, 
there 
is 
no 
evidence 
that 
the 
City 
intentionally created a nuisance——that is, an interference with 
MMSD's use and enjoyment of its sewer.  This is not a case where 
the nuisance condition is created by the very nature of the 
defendant's activities and operations, such as the case with a 
slaughterhouse or tannery.  Rather, the allegations in the 
present case are more analogous to the second class of cases 
identified in Brown and the Restatement's provisions regarding a 
failure to act.  Water mains are generally beneficial to 
property owners.  It is only when, over time, through the 
natural process of corrosion and the City's negligence in 
No. 
02-2961   
 
23 
 
repairing and maintaining its mains that the pipes leak, break, 
or otherwise create a condition that interferes with the private 
use and enjoyment of property.   
¶41 Indeed, the plaintiff's own complaint establishes that 
the allegations in this case involve the negligent failure of 
the City to act.  The complaint specifically alleges that "[t]he 
City  . . . permitted a nuisance condition to exist, to wit:  
the existence of [a] broken water main, which nuisance caused 
the collapse of the District's MIS." (Emphasis added.)  The 
initial act in laying the water main did not give rise to a 
cause of action; rather it is the City's alleged negligence in 
failing to act and repair a leak in the water main that 
ultimately damaged MMSD's sewer and gave rise to the cause of 
action.  See CEW Mgmt., 88 Wis. 2d at 635-36 (illustrating that 
defendant's actions did not give rise to a claim for nuisance 
until such conduct resulted in an interference with plaintiff's 
property).  Thus, the court of appeals erred in concluding that 
this case involved the intentional creation of a nuisance.  
¶42 Having determined that the nuisance in this case is 
premised on the City's alleged negligence in failing to repair 
its leaky water main——that is, failure to abate a nuisance——we 
turn now and examine the requisite elements for liability for a 
nuisance based on negligent conduct.  As noted supra, the 
failure to distinguish between a nuisance and the wrongful 
conduct necessary to establish liability for the nuisance has 
resulted in much confusion in the area of nuisance law.  In 
particular, there has been much confusion surrounding the 
No. 
02-2961   
 
24 
 
relationship between nuisance and negligence.  In Physicians 
Plus, this court noted the confusion regarding these two 
concepts and sought to clarify the relationship between the two.  
Physicians Plus, 254 Wis. 2d 77, ¶20.  
¶43 In Physicians Plus, we recognized that the concepts of 
negligence and nuisance overlap when a nuisance is predicated on 
negligent conduct, id., 254 Wis. 2d 77, ¶27, but nonetheless 
stressed that the two concepts are distinct:  "'The point is 
that nuisance is a result and negligence is a cause . . . .'"  
Id., ¶27 n.22 (quoting Culwell v. Abbott Constr. Co., 506 P.2d 
1191, 1196 (Kan. 1973)); See also CEW Mgmt., 88 Wis. 2d at 636.  
In other words, "nuisance has reference to the interest invaded 
and negligence to the conduct that subjects the actor to 
liability for the invasion."  Restatement (Second) of Torts 
§ 822 cmt. b.  As such, "a person may not recover damages from a 
private unintentional nuisance in the absence of underlying 
negligent . . . conduct . . . or 
activities." 
 
Stunkel, 
229 
Wis. 2d at 667.  See also Restatement (Second) of Torts § 822 
cmt. c. 
¶44 Therefore, an essential element of a private nuisance 
claim grounded in negligence is proof that the underlying 
conduct is "otherwise actionable under the rules controlling 
liability for negligent . . . conduct."  Restatement (Second) of 
Torts § 822.  See also Fortier v. Flambeau Plastics Co., 164 
Wis. 2d 639, 676, 476 N.W.2d 593 (Ct. App. 1991)(plaintiff's 
claim for private nuisance could proceed to the extent it was 
based on common-law negligence).  A corollary to this principle 
No. 
02-2961   
 
25 
 
is that when a nuisance is grounded solely on negligent acts, 
there is no need to separately analyze a cause of action for 
negligence and nuisance because the negligence is but the 
tortious conduct upon which liability for the result——the 
nuisance——depends.  Where an alleged nuisance is not based upon 
intentional conduct, "'[i]t necessarily follows that if there 
was no negligence there was no nuisance.'"  Lange v. Town of 
Norway, 77 Wis. 2d 313, 321, 253 N.W.2d 240 (1977)(quoting 
Raisanen v. City of Milwaukee, 35 Wis. 2d 504, 514-15, 151 
N.W.2d 129 (1967)).  Thus, when the plaintiff's complaint does 
not allege intentional conduct and negligence is not properly 
proved, the "'[p]laintiff add[s] nothing to the sufficiency of 
the complaint by his allegations of nuisance.'"  Id. (quoting 
Raisanen, 35 Wis. 2d at 514).  See also Bratonja v. City of 
Milwaukee, 3 Wis. 2d 120, 126-27, 87 N.W.2d 775 (1958)(ruling 
that where cause of action is predicated upon negligent conduct 
"the designation 'nuisance' is a mere label, adding nothing to 
the case asserted on the basis of negligence").9 
¶45 Since 
proof 
of 
negligence 
is 
essential 
to 
a 
negligence-based nuisance claim, our courts have repeatedly held 
that when a nuisance claim is predicated upon negligence, the 
usual defenses in a negligence action are applicable.  See, 
e.g., Vogel, 201 Wis. 2d at 425; Stunkel, 229 Wis. 2d at 669-70.  
In Physicians Plus, we noted that prior case law had established 
                                                 
9 Therefore, we reject MMSD's contention that it may proceed 
on a negligence theory even if it fails to establish liability 
for nuisance.   
No. 
02-2961   
 
26 
 
that when a nuisance is founded on negligent conduct, "'the 
defendant should be accorded the same defenses that would be 
available in any other action grounded upon negligence.'"  
Physicians Plus, 254 Wis. 2d 77, ¶25 (quoting Schiro, 272 
Wis. at 546).  Thus, we ruled that when a claim is made that the 
defendant 
negligently 
maintained 
a 
nuisance, 
notice 
and 
causation are required to establish liability.  Id., ¶20.10   
¶46 MMSD argues that notice is not required in an action 
for private nuisance and emphasizes that Physicians Plus was a 
public nuisance case.  However, since the principal difference 
between a public and private nuisance lies in the nature of the 
interest violated or affected by the wrongful conduct, the 
elements 
required 
to 
establish 
liability 
for 
either 
are 
virtually identical.  Id., ¶21 & n.14, ¶25 n.21 (explaining the 
difference between a public and private nuisance and noting the 
similarity in analyses for public and private nuisance); 
Restatement (Second) of Torts § 821B cmt. e (stating that 
liability for public nuisance is governed by the same rules 
applicable to liability for private nuisance).   
¶47 In addition, while Physicians Plus was indeed a public 
nuisance case, Physicians Plus specifically quoted our earlier 
                                                 
10 We reject MMSD's contention that notice is not required 
because liability for a nuisance is based on the violation of an 
absolute duty.  As correctly noted by the court of appeals in 
Stunkel, 229 Wis. 2d at 670, while some older cases suggest a 
strict liability analysis, these cases are all consistent with 
the 
Restatement's 
provisions 
regarding 
intentional 
and 
unreasonable conduct.   
No. 
02-2961   
 
27 
 
decision in Schiro, for the proposition that when a nuisance is 
premised on negligent conduct, the defendant is entitled to all 
the usual defenses to negligence.  Physicians Plus, 254 
Wis. 2d 77, ¶25.  Schiro itself involved a private nuisance.  
Schiro, 272 Wis. at 545.  Since all the underlying rules of 
negligence are applicable to a claim of nuisance based on 
negligence, Schiro, 272 Wis. at 546; Vogel, 201 Wis. 2d at 425; 
Stunkel, 229 Wis. 2d at 669; Restatement (Second) of Torts § 822 
& cmt. h, logically then, the prerequisites for liability should 
not vary depending upon whether the interest invaded by the 
defendant's negligent conduct is public or private.   
¶48 Here, MMSD alleges that the City was negligent in 
failing to repair the water main before it broke.  As discussed 
supra, in Brown we specifically stated that when liability for a 
nuisance is predicated upon a failure to act (failure to abate a 
nuisance), notice of the defective condition is a prerequisite 
to liability.  Brown, 199 Wis. at 589-90.  The Restatement 
(Second) of Torts § 824 provides that no liability for nuisance 
can attach based on a failure to act unless the actor was under 
a duty to act——that is, unless he has knowledge or notice of the 
nuisance condition.  Further, in Schiro, 272 Wis. at 546-47, we 
noted that when a nuisance is premised on negligent conduct, 
failing to allow the defendant the same defenses as he would 
have in a negligence action would render liability dependent on 
the label the plaintiff used on the pleading and not the 
defendant's underlying conduct.  We therefore conclude that 
notice is a necessary part of the plaintiff's proof in an action 
No. 
02-2961   
 
28 
 
for nuisance when liability is predicated upon the defendant's 
alleged negligent failure to act, regardless of whether the 
nature of the harm is public or private.   
¶49 In sum, in order to maintain an action for a private 
nuisance, there must be proof that there exists an invasion or 
interference with the private use and enjoyment of land, the 
defendant's conduct was the legal cause of the invasion, and the 
defendant's conduct is actionable under the rules relating to 
intentional or negligent conduct.  When liability for a nuisance 
is predicated upon negligent conduct, it is necessary to 
establish 
both 
the 
existence 
of 
a 
private 
nuisance——an 
interference with the private use and enjoyment of land——and 
that the conduct causing the harm is actionable under the rules 
governing liability for negligent conduct, including notice.   
C. 
Governmental Immunity  
¶50 Before addressing whether MMSD has established a prima 
facie case for a negligence-based nuisance, we must first 
consider the question of governmental immunity.11  MMSD argues 
that under the common law, a municipality is never immune from 
nuisance suits involving the invasion of a private interest in 
                                                 
11 Because we have concluded that the record does not 
support a claim of nuisance based on intentional conduct, we 
consider only whether the City is immune from liability for a 
negligence-based nuisance.  We do not consider whether immunity 
would apply to a claim of nuisance premised on conduct that 
would constitute an intentional tort.  But see, Lange v. Town of 
Norway, 77 Wis. 2d 313, 320-21, 253 N.W.2d 420 (1977); Salerno 
v. 
Racine, 
62 
Wis. 2d 243, 
245, 
214 
N.W.2d 446 
(1974); 
Envirologix Corp. v. City of Waukesha, 192 Wis. 2d 277, 288, 531 
N.W.2d 357 (Ct. App. 1995).   
No. 
02-2961   
 
29 
 
land, whereas the City argues that it enjoys immunity in this 
case under § 893.80(4) because all the acts complained of are 
legislative or quasi-legislative acts.  Both parties are 
incorrect.   
¶51 The starting point for an analysis of the common-law 
immunity of a governmental entity for nuisance is the much cited 
case of Winchell, 110 Wis. at 103-04, where the plaintiff, a 
riparian landowner, alleged the defendant had created a nuisance 
through the installation of a sewage system that defiled the 
waters adjoining her land.  The court held that the city was 
subject to the same liability as an individual would be, id. at 
110, stating, "legislative authority to install a sewer system 
carries no implication of authority to create or maintain a 
nuisance, and that it matters not whether such nuisance results 
from negligence or from the plan adopted."  Id. at 109.  
Numerous other older cases routinely found that governmental 
entities were liable in negligence or nuisance for damage caused 
by various public works.  See, e.g., Stockstad v. Town of 
Rutland, 8 Wis. 2d 528, 532-34, 99 N.W.2d 813 (1959); State 
Journal Printing Co. v. City of Madison, 148 Wis. 396, 397, 403-
04, 134 N.W. 909 (1912); Piper v. City of Madison, 140 Wis. 311, 
314-15, 122 N.W. 730 (1909).   
¶52 In these early cases, immunity questions were decided 
based on the rule that a governmental entity was generally 
immune from suits in tort unless it was deemed to be engaged in 
a 
"proprietary 
function" 
or 
the 
relation 
between 
the 
governmental entity and the plaintiff was not that of "governor 
No. 
02-2961   
 
30 
 
to governed."  See Holytz, 17 Wis. 2d at 32, 36.  In the 
landmark decision of Holytz, the court abandoned the older 
distinctions between proprietary and governmental functions in 
relation to government immunity.  Id. at 39.12  The court 
abrogated 
the 
general 
rule 
of 
governmental 
immunity 
for 
municipalities, stating:  "henceforward, so far as governmental 
responsibility for torts is concerned, the rule is liability——
the exception is immunity."  Id.  However, the court retained an 
immunity exception for the liability of a municipality for acts 
done "in the exercise of its legislative or judicial or quasi-
legislative or quasi-judicial functions."  Id. at 40.    
¶53 Following Holytz, the legislature enacted Wis. Stat. 
§ 331.43 (1963), which is currently codified as § 893.80(4).13  
We recognized in Lange, 77 Wis. 2d at 314-18, that this statute 
codified 
the 
holding 
in 
Holytz 
regarding 
immunity 
for 
legislative, judicial, quasi-legislative, and quasi-judicial 
acts.  Wisconsin Stat. § 893.80(4) provides:  
No suit may be brought against any . . . political 
corporation, governmental subdivision or any agency 
thereof for the intentional torts of its officers, 
                                                 
12 While several court of appeals decisions have relied on 
these earlier cases, in Holytz v. City of Milwaukee, 17 
Wis. 2d 26, 39, 115 N.W.2d 618 (1962), this court clearly 
rendered 
obsolete 
the 
logic 
upon 
which 
the 
immunity 
determinations in these cases were based.    
13 The legislature changed the statutory numbering to Wis. 
Stat. § 895.43 in 1965, and Wis. Stat. § 893.80 in 1979. See 
§ 2, ch. 66, Laws of 1965; § 29, ch. 323, Laws of 1979.  The 
pertinent language in the statute has remained unchanged 
throughout its renumbering.   
No. 
02-2961   
 
31 
 
officials, agents or employees nor may any suit be 
brought 
against 
such 
corporation, 
subdivision 
or 
agency . . . for 
acts 
done 
in 
the 
exercise 
of 
legislative, quasi-legislative, judicial or quasi-
judicial functions.   
¶54 We have recognized that § 839.80(4) "immunizes against 
liability for legislative, quasi-legislative, judicial, and 
quasi-judicial acts, which have been collectively interpreted to 
include any act that involves the exercise of discretion and 
judgment."  Lodl v. Progressive N. Ins. Co., 2002 WI 71, ¶21, 
253 Wis. 2d 323, 646 N.W.2d 314.  See also Envirologix Corp. v. 
City of Waukesha, 192 Wis. 2d 277, 288, 531 N.W.2d 357 (Ct. App. 
1995)("The terms 'legislative, quasi-legislative, judicial or 
quasi-judicial' 
are 
synonymous 
with 
the 
term 
'discretionary.'")(internal citation omitted).  In contrast, we 
have recognized that the second clause of § 893.80(4) affords no 
protection 
to 
a 
municipality 
for 
nondiscretionary 
or 
"ministerial" acts:   
A ministerial act, in contrast to an immune 
discretionary act, involves a duty that "is absolute, 
certain 
and 
imperative, 
involving 
merely 
the 
performance of a specific task when the law imposes, 
prescribes and defines the time, mode and occasion for 
its performance with such certainty that nothing 
remains for judgment or discretion."   
Willow Creek Ranch, L.L.C. v. Town of Shelby, 2000 WI 56, ¶27, 
235 Wis. 2d 409, 611 N.W.2d 693 (quoting C.L. v. Olson, 143 
Wis. 2d 701, 711-12, 422 N.W.2d 614 (1988)(quoting Lister v. Bd. 
of Regents, 72 Wis. 2d 282, 301, 240 N.W.2d 610 (1976))).   
No. 
02-2961   
 
32 
 
¶55 Following Holytz and the enactment of the immunity 
statute, this court decided Lange, 77 Wis. 2d at 314,14 where the 
plaintiff alleged that a town negligently maintained a dam and 
that the operation of the dam constituted a nuisance because it 
caused the waters of a nearby lake to back up and flood his 
lands.  Reviewing the circuit court's order dismissing the 
plaintiff's complaint, the court addressed the immunity statute 
and recognized that the statute was enacted by the legislature 
in response to the Holytz decision.  Id. at 317 n.3.  The court 
concluded that under the immunity statute, the town was immune 
from any liability predicated upon its acquisition of the 
existing dam or construction of a new dam because "these are 
clearly legislative functions under the statute."  Id. at 318.   
¶56 Reviewing several immunity cases decided since the 
passage of the statute, the court concluded that while the town 
enjoyed immunity in regard to "the size of the dam acquired and 
the capacity of its floodgate," immunity did not extend to 
claims arising from negligence in operating or maintaining the 
                                                 
14 Prior to Lange, this court decided Costas v. City of Fond 
du Lac, 24 Wis. 2d 409, 411, 129 N.W.2d 217 (1964), where the 
plaintiffs brought an action against a city to abate a private 
nuisance caused by gases emanating from the city's sewage 
disposal plant.  The court concluded that a city has no immunity 
for the "plan adopted" for a public works system.  Id. at 416.  
However, Costas is not controlling on this point, as its holding 
was based on Winchell v. City of Waukesha, 110 Wis. 101, 109, 85 
N.W. 668 (1901), which predated Holytz and the enactment of the 
immunity statute.  Notably, the court in Costas did not even 
mention the Holytz decision or the newly enacted immunity 
statute, Wis. Stat. § 331.43 (1963). 
 
No. 
02-2961   
 
33 
 
existing dam.  Id. at 318-20.  The court held that immunity 
"would not include a failure to maintain as to a condition of 
disrepair or defect or a failure to operate said floodgate."  
Id. at 320.  Finally, the court stated that if the nuisance was 
based upon negligence in operating and maintaining the dam, acts 
to which immunity did not apply, there was no need to separately 
analyze the nuisance question from the negligence question as 
"'nothing is added' by terming the required negligence to 'as 
such' constitute maintaining a public nuisance."  Id. at 321.   
¶57 In Allstate Insurance Co. v. Metropolitan Sewerage 
Commission, 80 Wis. 2d 10, 12, 258 N.W.2d 148 (1977), the 
plaintiffs' insureds were injured in an automobile accident 
resulting from a truck operated by the defendant that was 
discharging effluent into a sewer system and blocking traffic.  
The complaint alleged that the defendant was negligent in 
"designing and placing the manhole when it knew or should have 
known" that its use would block traffic and it failed to take 
precautions to prevent the blocking of traffic.  Id. at 14.  The 
dispostive issue on appeal was whether immunity barred any of 
the claims against the various defendants.  Id. at 14-15.  The 
court concluded that all the alleged acts or failures to act by 
the various municipal corporations "were either legislative or 
quasi-judicial and, as such, [were] immune under sec. 895.43, 
Stats."  Id. at 18. 
¶58 In so holding the court ruled that decisions in 
"planning and designing the system in question, including the 
placement of the manhole, were legislative acts.  Id. at 15.  
No. 
02-2961   
 
34 
 
The court stated that "[w]here, when and how to build sewer 
systems 
are 
legislative 
determinations 
imposed 
upon 
a 
governmental body."  Id. at 16.  (Emphasis added.)  Further, the 
governmental entity that approved the plans was acting in either 
a legislative or quasi-judicial capacity when approving such 
plans.  Id.  Moreover, the court ruled that so long as the 
manhole was placed at a location in compliance with the sewer 
plans, its placement was an act in compliance with a legislative 
act that was also subject to immunity.  Id.  The court ruled 
that these initial planning and implementation decisions were 
covered by immunity even though the "subsequent use of the 
manhole may have created a danger."  Id.15   
¶59 Therefore, it is clear that under the law since Holytz 
and the enactment of the immunity statute that a municipality 
may be liable for a nuisance founded upon negligent acts.  
                                                 
15 Therefore, the holdings in Allstate Insurance Co. v. 
Metropolitan 
Sewerage 
Commission, 
80 
Wis. 2d 10, 
15, 
258 
N.W.2d 148 (1977), and Lange, 77 Wis. 2d at 318, 321, based upon 
the predecessor to § 893.80(4), effectively overruled, sub 
silencio, the language in Costas, 24 Wis. 2d at 416, that a city 
has no immunity for the "plan adopted" for a public works 
system.  As noted supra, this language from Costas was based on 
law that predated Holytz and the immunity statute.  Conversely, 
both Lange and Allstate were post-Holytz decisions whose 
holdings were based on the express language in the immunity 
statute.   
No. 
02-2961   
 
35 
 
Lange, 77 Wis. 2d at 320.16  Whether immunity exists for nuisance 
founded on negligence depends upon the character of the 
negligent acts.  If the acts complained of are legislative, 
quasi-legislative, 
judicial, 
or 
quasi-judicial——that 
is 
discretionary——the municipality is protected by immunity under 
§ 893.80(4). 
 
Lodl, 
253 
Wis. 2d 323, 
¶21; 
Allstate, 
80 
Wis. 2d at 18; Lange, 77 Wis. 2d at 318.  Conversely, immunity 
does not apply if the negligence involves an act performed 
pursuant to a ministerial duty.  Willow Creek, 235 Wis. 2d 409, 
¶27; Allstate, 80 Wis. 2d at 16-17.  Thus, when analyzing claims 
of immunity under § 893.80(4) for nuisances, the proper inquiry 
is to examine the character of the underlying tortious acts.17  
                                                 
16 See also Chart v. Dvorak, 57 Wis. 2d 92, 100-01, 203 
N.W.2d 673 (1973)(ruling that once a governmental body makes a 
legislative or quasi-legislative decision to install a highway 
sign, it is under a duty to maintain such sign without 
negligence); Dusek v. Pierce County, 42 Wis. 2d 498, 505, 167 
N.W.2d 246 (1969)(noting that a municipality may be liable for 
failure to maintain highway signs after Holytz). 
17 Several court of appeals decisions, upon which the 
parties in this case rely, have applied the immunity statute to 
a variety of nuisance claims involving sanitary and storm sewers 
and have utilized conflicting rationales to reach results that 
are not entirely consistent.  See, e.g., Welch v. City of 
Appleton, 2003 WI App 133, 265 Wis. 2d 688, 666 N.W.2d 511; 
Anhalt v. Cities and Vills. Mut. Ins. Co., 2001 WI App 271, 249 
Wis. 2d 62, 637 N.W.2d 422; Menick v. City of Menasha, 200 
Wis. 2d 737, 547 N.W.2d 778 (Ct. App. 1996); Hillcrest Golf & 
Country Club v. City of Altoona, 135 Wis. 2d 431, 400 N.W.2d 493 
(Ct. App. 1986)[hereinafter Hillcrest].   
No. 
02-2961   
 
36 
 
Finally, when a nuisance is grounded solely upon negligent acts, 
there is no need to separately analyze the immunity question for 
both negligence and nuisance because liability for the nuisance 
cannot be established without proof of negligence.  Lange, 77 
Wis. 2d at 321 (citing Raisanen, 35 Wis. 2d at 514-15).18    
¶60 Applying these rules to the facts of the present case, 
it is clear that decisions regarding the adoption, design, and 
implementation of public works are discretionary, legislative or 
quasi-legislative acts subject to immunity.  Allstate, 80 
Wis. 2d at 15-17; Lange, 77 Wis. 2d at 317-18.  "Approval of the 
design and construction of a [public work] are generally 
                                                                                                                                                             
To the extent these decisions have created confusion in the 
area of municipal immunity for nuisances, such confusion is a 
result of three factors.  First, some decisions have continued 
to rely on immunity jurisprudence that predated Holytz and 
§ 893.80(4).  See, e.g., Hillcrest, 135 Wis. 2d at 438-41.  
Second, some decisions employ separate analyses for negligence 
and nuisances grounded in negligence.  See, e.g., Welch, 265 
Wis. 2d 688, ¶¶8-13.  Third, some decisions fail to stress that 
a municipality is liable for its negligent acts only if those 
acts are performed pursuant to a ministerial duty.  See, e.g., 
Anhalt, 249 Wis. 2d 62, ¶26. 
Focusing the immunity analysis on the character of the 
tortious acts underlying the nuisance is important for two 
reasons.  First, as discussed supra, liability for nuisance is 
itself dependent upon whether the underlying tortious conduct is 
actionable. 
 
Second, 
and 
more 
importantly, 
Wis. Stat. § 893.80(4) does not immunize municipalities for 
certain results; rather, immunity is provided for certain acts.    
18 Thus, the court of appeals in the instant case misstated 
the 
law 
when 
it 
concluded 
that 
§ 893.80(4) 
immunizes 
a 
municipality from a cause of action alleging negligence but not 
a nuisance claim that is based in negligence.  Milwaukee Metro. 
Sewerage Dist., 2003 WI App 209, ¶22, 267 Wis. 2d 688, 671 
N.W.2d 346.   
No. 
02-2961   
 
37 
 
discretionary 
acts . . . . 
Even 
if 
the 
system 
is 
poorly 
designed, 
a 
municipal 
government 
is 
immune 
for 
this 
discretionary act."  Welch v. City of Appleton, 2003 WI App 133, 
¶13, 265 Wis. 2d 688, 666 N.W.2d 511.  Therefore, the City is 
immune from suit relating to its decisions concerning the 
adoption of a waterworks system, the selection of the specific 
type of pipe, the placement of the pipe in the ground, and the 
continued existence of such pipe.  These are discretionary 
legislative decisions.19   
¶61 The only act for which the City may be potentially 
liable is its failure to repair the leaking water main.  As MMSD 
has not alleged that the City was negligent in failing to repair 
the main after it broke, the question then becomes whether the 
City was under a ministerial duty to repair the leaking main 
before it broke.  As noted supra, a duty is ministerial "only 
when it is absolute, certain and imperative, involving merely 
the performance of a specific task when the law imposes, 
prescribes and defines the time, mode and occasion for its 
performance with such certainty that nothing remains for 
judgment or discretion."  Lister, 72 Wis. 2d at 301. 
                                                 
19 As in Allstate, 80 Wis. 2d at 16 n.5, we express no 
opinion as to "whether municipal immunity attached to the 
planning 
function 
should 
persist 
in 
view 
of 
subsequent 
experience or changed conditions which demonstrate an actual and 
substantial danger."  That is, we do not determine whether a 
governmental entity has "a duty to review its legislative 
determination[s] 
after 
notice 
that 
a 
dangerous 
condition 
exists[.]"  Id.   
No. 
02-2961   
 
38 
 
¶62 Having reviewed the record, we determine that the 
facts of the present case are not sufficiently developed for us 
to determine whether the City was under a ministerial duty to 
repair the leaking main prior to its break on December 9, 1999.  
As will be discussed below, there is a material issue of fact as 
to whether the City had notice of the leaking water main prior 
to its break.  Since we cannot determine whether the City was on 
notice that its water main was leaking and could potentially 
interfere with the use and enjoyment of another's property, we 
cannot conclude whether its duty to repair the leaking main with 
reasonable care before it broke was "absolute, certain and 
imperative," Lister, 72 Wis. 2d at 301, or whether the City's 
decision 
not 
to 
repair 
the 
main 
before 
the 
break 
was 
discretionary.  As such, we cannot determine whether the City is 
entitled to governmental immunity under § 893.80(4) based on the 
record before us.  Thus, the circuit court must consider this 
issue on remand.   
D. 
Summary Judgment  
¶63 Having determined that the only actionable claim in 
this case is one for negligently failing to abate a nuisance, we 
lastly examine whether the circuit court properly granted 
summary judgment in this case.  As we previously discussed, in 
order to prevail on a claim of nuisance based on negligence, the 
plaintiff must prove the following elements:  1) The existence 
of a private nuisance——the interference with another's interest 
in the private use and enjoyment of land; 2) The defendant's 
conduct is the legal cause of the private nuisance; and 3) The 
No. 
02-2961   
 
39 
 
defendant's conduct is otherwise actionable under the rules 
governing liability for negligent conduct, including notice.  
Here, MMSD has established the first element——an interference 
with its interest in the use and enjoyment of its MIS line.  The 
parties contest whether there are any disputed issues of 
material fact relating to causation and notice of the leaky 
pipe.  We will discuss the causation issue first and then 
examine the notice issue.  
1. 
Causation 
¶64 With regard to causation, the court of appeals in 
Menick v. City of Menasha, 200 Wis. 2d 737, 747, 547 N.W.2d 778 
(Ct. App. 1996), correctly noted that a negligence-based 
nuisance requires proof of causation, which may require expert 
testimony if falling outside the realm of ordinary experience 
and comprehension.  Viewing the summary judgment materials in a 
light most favorable to MMSD, we believe that there is a genuine 
issue of material fact relating to causation.  There is clearly 
conflicting testimony in the record relating to the cause of the 
water main break and the MIS collapse.   
¶65 Throughout the course of this litigation, the parties 
have disputed whether the water main broke first causing the MIS 
to collapse or whether the MIS collapsed first, thereby causing 
the City's water main to fracture and break.  Prior to the 
incident in this case, MMSD had engaged the Rust/Harza firm to 
investigate the Central MIS system in order to evaluate its 
current condition and recommend improvements.  An employee of 
Rust/Harza who investigated the MIS collapse, Patrick Murray, 
No. 
02-2961   
 
40 
 
stated in his deposition that the MIS sewer "is in poor 
condition and susceptible to failure."  However, Mr. Murray 
later signed an affidavit retracting this part of his deposition 
testimony.  A MMSD employee, Larry Osieczonek, testified that he 
inspected the MIS the day of the water main break and observed 
water to be flowing normally through the MIS.  Timothy Bate, a 
MMSD engineer, stated that prior to the collapse, the MIS was 
functioning normally and that while it was old, MMSD had no 
information to suggest that the MIS was in any danger of 
collapse.   
¶66 During the course of its investigation of the MIS 
collapse, MMSD procured and examined soil samples from the break 
site.  MMSD also sent the broken portion of the water main to a 
lab for analysis.  Steven DeMuth, one of MMSD's named experts, 
inspected and tested the section of the broken pipe at a 
laboratory to determine if there were any fractures in the pipe 
and the age of any such fractures.  He testified that the pipe 
looked "in very good condition" for its age.  He found some 
graphite corrosion in the pipe but opined that the corrosion was 
relatively recent and "seemed very minor."  He also stated that 
he saw "no reason that this pipe would go in for replacement."  
In addition, he was unable to find any internal flaw in the 
piping materials.20   
                                                 
20 After analysis, the lab discarded the pipe.  Thus, the 
City did not have an opportunity to have its own experts examine 
the pipe.   
No. 
02-2961   
 
41 
 
¶67 Another MMSD expert, Steven Fradkin, a geologist, 
testified that there was no clear answer as to whether the MIS 
collapsed first causing the water main to break or whether the 
water main cracked first.  However, he testified that given the 
age of the MIS, it was likely that there had been movement of 
its bricks.  This testimony was contradicted by a Rust/Harza 
geotechnical engineer, Steven Hunt, who testified that the MIS 
was located in stable material and "wasn't at great risk of 
becoming unstable" due to soil breaching the brick.  In 
contrast, Mr. Hunt indicated that the soil surrounding the water 
main was corrosive.21   
¶68 Ronald Heuer, another MMSD expert who examined boring 
samples taken of the soil in the break area, testified that 
there was a "strong," "more than reasonable" likelihood that the 
MIS collapse was triggered by the water leakage from the City's 
water main.  However, when pressed he would not say his opinion 
was rendered "to a reasonable degree of scientific certainty."  
Yet, he stated that the soil under the water main was loose and 
that the downward movement of this soil eventually caused the 
break in the main.  
¶69 Similarly, Mr. Murray stated in his deposition that 
following an examination of the broken water main, "he could not 
state with certainty what caused either the MIS or water main to 
                                                 
21 Mr. Scheller stated in his affidavit that the City 
changed 
the 
material 
it 
used 
as 
fill 
during 
the 
main 
installation process to limestone in the 1970s to reduce the 
risk of water main corrosion.   
No. 
02-2961   
 
42 
 
fail."  However, he further noted that while both pipes were old 
and susceptible to failure, the "age of the water main fractures 
and the time of the collapse tends to point to the water main 
failing first."     
¶70 Douglas Chisholm, another MMSD expert, testified that 
the fracture in the pipe existed somewhere between .8 and 2.6 
years and that the pipe was leaking over this period of time.  
However, he could not state when the pipe actually broke.  Mr. 
Chisholm testified that the water main was subjected to some 
outside force that caused the breach in the water pipe.  When 
asked about the initial cause of the fracture, Mr. Chisholm 
stated that it was possible that the pipe was damaged as a 
result of a nearby construction program that took place sometime 
in 1992-93.22  Mr. Chisholm testified that old cast iron pipe is 
"enormously susceptible to outside force" and that it is 
important to monitor or replace old cast iron pipe; yet, he was 
aware of no evidence that the pipe began to crack when the 1993 
construction project took place.  Mr. Heuer testified that 
"[t]he disturbance related to that construction activity could 
be an explanation for why the water main was fractured." 
¶71 However, the City's water main design engineer, Mr. 
Scheller, stated in an affidavit that while the contractors on 
                                                 
22 This construction project related to renovation work done 
on the Wisconsin Avenue Bridge.  Apparently, during the 
construction project, a wall supporting a "duct package" 
collapsed 20 feet from the water main in question.  The 
contractors subsequently repaired the duct package by adding 
extra support to it.   
No. 
02-2961   
 
43 
 
the 1993 construction project experienced some problems near the 
location of the 8-inch water main, "there is no documentation 
whatsoever which establishes that the . . . construction project 
caused any damage to the 8 inch water main."  Mr. Scheller 
testified that "[t]here is no indication in any record that the 
collapse of the supporting wall caused any damage to the water 
main located in the area."  Mr. Scheller stated that since this 
construction project ended, "there have been no complaints, 
repairs, or any problems documented whatsoever, with reference 
to any water main" in the area in question.   
¶72 Viewing the summary judgment materials in a light most 
favorable to the nonmoving party, MMSD, we conclude that there 
exists a disputed issue of material fact relating to causation.  
In addition, the court of appeals' decision leaves open the 
possibility that the circuit court can issue an instruction on 
res ipsa loquitur.  Milwaukee Metro. Sewerage Dist., 267 
Wis. 2d 688, ¶26.   
2. 
Notice 
¶73 MMSD's complaint alleges that the City's failure to 
repair a leaky water main resulted in the collapse of their MIS.  
In order to survive summary judgment, there must be evidence in 
the record such that a reasonable jury could find that the City 
had notice of the leaky pipe and was therefore negligent in 
failing to repair it.  Notice of the nuisance condition may be 
either actual or constructive.  Physicians Plus, 254 Wis. 2d 77, 
¶29; Restatement (Second) of Torts § 839 (A possessor of land is 
liable for failing to abate a nuisance if he "knows or should 
No. 
02-2961   
 
44 
 
know of the condition and the nuisance.").23  In Walley v. 
Patake, 271 Wis. 530, 542-43, 74 N.W.2d 130 (1956), we stated 
that in an action for maintaining a nuisance, there must be 
proof that the condition causing the nuisance existed long 
enough that the defendant knew or should have known of the 
condition and could have remedied it within a reasonable amount 
of time.  MMSD has agreed that the City did not have actual 
notice of the leaky water main.  Thus, we must determine whether 
the summary judgment materials, viewed in a light most favorable 
to MMSD, would allow a reasonable fact-finder to conclude that 
the City had constructive notice——that is, should have known——of 
the leaky pipe.   
¶74 Generally, constructive notice "may arise from any 
observable condition existing over a period of time [that is] 
indicative that a leak has or is likely to occur."  C.T. 
Drechsler, Annotation, Liability of Water Distributor for Damage 
Caused by Water Escaping from Main, 20 A.L.R. 3d 1294, § 11 
(1968)[hereinafter Liability of Water Distributor].  See also 78 
Am. Jur. 2D Waterworks and Water Companies § 61 (2003)(accord).  
The constructive notice requirement is important in this context 
because a water main is a closed conduit buried several feet 
below the street that is not readily susceptible to inspection 
                                                 
23 However, the duty to abate "is not an absolute duty to 
prevent harm to others at all costs, but merely a duty to do 
what is practicable and reasonably under the circumstances."  
Restatement (Second) of Torts § 839 cmt. e.  In addition, the 
condition must be reasonably susceptible to being abated.  
Restatement (Second) of Torts § 839 cmt. f.   
No. 
02-2961   
 
45 
 
in the same manner as a sewer.  Republic Light & Furniture Co. 
v. City of Cincinnati, 127 N.E.2d 767, 772 (Ohio Ct. App. 1954).  
Another court has noted that if a city were under an absolute 
duty to constantly dig up its streets and examine its pipes 
without any notice of a problem, "[t]he expense of maintaining a 
system under those circumstances would be such as to make the 
cost of supplying water prohibitive."  Brown & Son, Inc. v. City 
of Grand Rapids, 251 N.W. 561, 562-63 (Mich. 1933).   
¶75 MMSD sets forth four arguments as to why constructive 
notice is present in this case.  First, MMSD argues that the 
main in question was leaking for up to two years before it 
ruptured and that the City should have learned of the leak 
during this time.  As noted, one of MMSD's experts testified 
that the fracture in the pipe existed somewhere between .8 and 
2.6 years and that the pipe was leaking over this period of 
time.  Mr. DeMuth concluded that the fractures in the pipe were 
recent, as they had probably existed for only a few weeks or 
months.  Mr. Heuer testified that the leakage from the water 
main was a gradual process and that while he could not quantify 
the rate at which water was escaping, he noted there were 
several fractures in the pipe that indicated water was probably 
leaking from the pipe for a number of years.   
¶76 The 
problem 
with 
MMSD's 
reliance 
on 
the 
above 
testimony is that while it establishes the length of time in 
which the water main was leaking, it does not establish that the 
City should have been aware of the leak.  Our cases have 
established 
that 
when 
a 
nuisance 
action 
is 
grounded 
in 
No. 
02-2961   
 
46 
 
negligence and there is no actual knowledge of the condition 
that interferes with the use and enjoyment of land, there must 
be proof demonstrating "the existence of the condition resulting 
in [the] alleged nuisance for a sufficient length of time so 
that the defendants knew or ought to have known of it, and could 
within a reasonable period have remedied it."  Walley, 271 Wis. 
at 543.  The Walley court further stated that there can be no 
liability for nuisance in these circumstances when there has not 
been a showing "that the condition had been maintained over an 
unreasonable period of time."  Id. at 542.  Stated differently, 
it must be shown that "the defendant failed to act under 
circumstances in which it had a duty to take positive action to 
prevent the invasion of the plaintiff's property."  CEW Mgmt., 
88 Wis. 2d at 636-67.24   
¶77 Mr. Heuer specifically testified that the leak was not 
visually identifiable until the main had completely ruptured. He 
stated that at the critical early stages of the main failure, 
there would have been no physical manifestation of the problem 
at street level:  "[T]he critical things started much earlier at 
a time when you can't see anything on the surface."  He 
testified that by the time any problem visually manifested 
itself on the surface, the collapse was in process and it would 
have been too late to do anything about it:  "By that stage, 
                                                 
24 See also Restatement (Second) of Torts § 839 cmt. i 
("What the possessor should know, therefore, depends first upon 
whether his land is in such condition that he, as a reasonable 
man, would be led to believe that it might be in a harmful 
condition and that an inspection of it was necessary.").   
No. 
02-2961   
 
47 
 
it's all over . . . . And there's nothing you can do now, just 
get out of the way and let it stabilize, and then you can go 
back and do something."25  There is no testimony that the City 
should have discovered the leaky pipe through the exercise of 
ordinary care solely because the leak existed for up to two 
years.    
¶78 MMSD's second argument is that the City should have 
conducted periodic inspections or tests of its water mains in 
the exercise of ordinary care and, had it done so, it would have 
discovered the condition of the leaky pipe.  MMSD argues that 
the City once employed a system of pressure testing its pipes 
and that it recently abandoned this system, electing to simply 
repair mains once they break.    
¶79 There are several flaws in MMSD's second argument.  
First, as noted above, the uncontroverted testimony from one of 
MMSD's experts establishes that there would have been no 
observable indications that the pipe was leaking until it broke.  
He stated that the leak would not have visually manifested 
itself until it was too late to inspect and correct the problem.  
While a City employee responding to the scene of the break 
                                                 
25 "[B]ecause a water distributor is not an insurer against 
liability resulting from defective mains, but is only liable for 
its negligence, no liability may attach for damage from a broken 
main if it is shown that, upon notice of the leak, the water 
distributor took all reasonable measures to locate the defect 
and repair it."  78 Am. Jur. 2D Waterworks and Water Companies 
§ 60.  See also C.T. Drechsler, Annotation, Liability of Water 
Distributor for Damage Caused by Water Escaping from Main, 20 
A.L.R. 3d 1294, § 10b (1968)(accord).   
No. 
02-2961   
 
48 
 
noticed a large depression in the road, there is no evidence 
that such condition exited before the water main burst.26  "Most 
courts agree that in the absence of some circumstances tending 
to indicate a defective condition, a water distributor is not 
actionably negligent by failing to regularly dig up and inspect 
buried water mains."  Liability of Water Distributor, 20 A.L.R. 
3d 1294, § 9.  See also 78 Am. Jur. 2D Waterworks and Water 
Companies § 60 ("In the absence of circumstances tending to 
indicate a probable deficiency, a water main distributor is not 
negligent in failing to conduct regular inspections of its 
mains.").  Rather, a waterworks operator's duty to inspect and 
repair arises "[a]fter notice of a leak likely to cause damage."  
Liability of Water Distributor, 20 A.L.R. 3d 1294, § 10 
(emphasis added).27  Thus, there must be proof of facts that 
would lead a reasonable waterworks operator to conclude that 
there was a harmful condition on its property that would, in the 
course of ordinary care, require an inspection.  Once such a 
condition is shown, the operator is charged with constructive 
notice of any nuisance condition that would have been discovered 
                                                 
26 Constructive notice giving rise to a duty to inspect and 
repair may be found when there is "[p]ersistent wetness and 
surface depressions in the ground over the main."  78 Am. Jur. 
2D Waterworks and Water Companies § 61.   
27 Those jurisdictions that do impose an absolute duty upon 
a waterworks operator to inspect buried pipes do so because they 
hold such operators strictly liable under nuisance law for any 
leaks in the system.  See, e.g., Lubin v. Iowa City, 131 
N.W.2d 765, 770 (Iowa 1964).  
No. 
02-2961   
 
49 
 
in the course of a reasonable investigation.  Restatement 
(Second) of Torts § 839 cmt. i.. 
¶80 The above discussion leads to the second deficiency in 
MMSD's argument, that is, there is an utter lack of testimony in 
the record concerning the appropriate standard of care for a 
waterworks operator and whether this standard includes periodic 
pressure testing.  Regarding constructive notice and the duty to 
inspect, in Kunz v. City of Wauwatosa, 6 Wis. 2d 652, 657, 95 
N.W.2d 760 (1959), we stated that when a cause of action is 
based on negligently maintaining a nuisance, "[i]n order to 
substantiate a claim of nuisance it must be shown that the 
dangerous condition existed long enough so that by the exercise 
of ordinary care the defendant should have discovered the danger 
and removed it before the accident."  There are simply no 
depositions, affidavits, or other testimony in the record that 
establish that the exercise of reasonable care for a waterworks 
operator includes periodic pressure testing of water mains.     
¶81 In addition, the City argues that such a system of 
pressure testing is not feasible.  The City states that its 
water mains are all pressurized and operate in a grid, such that 
there is pressure constantly in the system.  It contends that 
pressure 
testing 
is 
dangerous, 
undermines 
the 
structural 
integrity of pipes, and would require the loss of service to its 
customers.  MMSD has put forth no evidence as to whether other 
municipalities regularly pressure test their pipes, the cost of 
such testing, the dangers involved, whether such testing is 
commonplace, and whether such testing would require extended 
No. 
02-2961   
 
50 
 
loss of service to customers.  Such matters are obviously beyond 
lay comprehension such that expert testimony would be required 
to establish that periodic pressure testing is feasible and part 
of the exercise of ordinary care for a reasonable waterworks 
operator.  See Olfe v. Gordon, 93 Wis. 2d 173, 180-82, 286 
N.W.2d 573 (1980).   
¶82 Were there testimony that a reasonable waterworks 
operator 
would, 
through 
the 
exercise 
of 
ordinary 
care, 
periodically pressure test its mains and would discover leaks in 
the system through such pressure testing, we would agree that 
the City's failure to pressure test its mains combined with the 
length of existence of the leak in question could constitute 
constructive notice of the leaking main.  However, nothing 
approaching this type of testimony appears in the record.   
¶83 Further, there is simply no evidence in the record 
that the City ever regularly employed a system of pressure 
testing its pipes.  According to a journal article written in 
the 1970s, which was made part of the record, the City did, at 
one time, experiment with pressure testing of older water mains 
that were abandoned and no longer in service.  Raymond J. Kocol, 
Pressure Testing the Distribution System in Milwaukee, J. Am. 
Water Works Ass'n, July 1972, at 430.  This journal article 
discusses 
an 
experimental 
pressure 
testing 
procedure 
and 
recommends that the City adopt a regular pressure testing 
program 
in 
conjunction 
with 
a 
comprehensive 
water 
main 
replacement program.  Id. at 433.  The article also explains 
that the tests were performed on pipes that were no longer in 
No. 
02-2961   
 
51 
 
service and that some of the testing was performed after the 
pipes had been removed from the ground.  Id. at 430-31.  
However, there is no evidence in the record that would indicate 
that the City ever adopted such a program or that the testing 
described in the article was anything more than a one-time 
experiment.  Indeed, the article notes that pressure testing "is 
still in the developmental stage," and refers to the City's 
"limited experience" with pressure testing.  Id. at 430.  The 
article further describes the project as a "basic research 
project."  Id.28   
¶84 MMSD's third argument in relation to notice is that 
there were two previous breaks that occurred in the water main 
in question in 1988 and 1989.  MMSD asserts that these breaks 
put the City on constructive notice that there may have been a 
leak in the system, such that further inspection was required.  
A Water Distribution Manager for Milwaukee Waterworks, Laura 
Daniels, stated in an affidavit that from the time the water 
main was installed at 40th and Bluemound until the water main 
break in question, there were two previous breaks in the 
surrounding four-block area.  The first break occurred in 1988 
                                                 
28  MMSD also cites to the deposition of Dinah Gant as proof 
that the City once employed pressure testing but stopped in 
1996.  However, Ms. Gant never testified that the City once 
employed a system of pressure testing.  Rather, counsel for MMSD 
queried:  "it sounded to me like you said you used to do 
pressure testing."  Ms. Gant responded by stating that there had 
not been any pressure testing since she joined Milwaukee 
Waterworks in 1996.  Nowhere in the portion of Ms. Gant's 
deposition that is in the record does she state that the City 
employed a system of pressure testing and then abandoned it.   
No. 
02-2961   
 
52 
 
and was located on 40th street, approximately 630 feet south of 
Bluemound Road.  The second break occurred in 1989 and was 
located on 40th street, approximately 1000 feet south of 
Bluemound Road.  Both breaks were described as "minor in nature, 
and were repaired in the normal course of business."  Ms. 
Daniels further stated that there was no record of any previous 
complaints or repairs within 579 feet of the break at issue in 
this case.  The record contains no further testimony concerning 
these leaks.   
¶85 Again, MMSD's argument fails because there is simply 
no testimony concerning the standard of care for a waterworks 
operator.  Constructive notice may be established by the 
existence "of previous breaks in the main at or near the break 
complained of . . . providing that the number of previous breaks 
is more than that which would be expected."  78 Am. Jur. 2D 
Waterworks and Water Companies § 61 (emphasis added).  Whether 
two minor breaks in a water main, each over 600 feet from the 
eventual leak, would place a reasonable waterworks operator on 
notice that there was a leak somewhere else in the system is 
certainly beyond normal lay comprehension.  Restatement (Second) 
of Torts § 839 cmt. i ("The possessor has a duty to inspect his 
premises and learn about harmful conditions on his land only 
when the circumstances are such that a reasonable person in his 
position would realize that there might be harmful conditions 
upon it.").   
¶86 Also, the extent to which a reasonable waterworks 
operator would conduct inspections in such circumstances is a 
No. 
02-2961   
 
53 
 
matter requiring special knowledge.  For instance, after notice 
of a previous leak, assuming it was of the type that would lead 
a reasonable waterworks operator to conduct an inspection, would 
a reasonable inspection include digging up 50 feet of pipe, 100 
feet of pipe, or 500 feet of pipe?  In other words, even 
assuming MMSD could prove either the 1988 or 1989 break, or 
both, were sufficient to put the City on notice of a leak 
somewhere else in the system, there is still no evidence as to 
what would constitute a reasonable inspection.   
¶87 MMSD's final argument regarding constructive notice is 
that the City was aware that the 1992-93 construction project 
could have damaged its water main and therefore the City was 
under a duty to inspect its pipe.  Mr. Chisholm testified that 
the water main in question was susceptible to damage from this 
construction 
project 
and 
Mr. 
Heuer 
testified 
that 
the 
construction project could be an explanation for the leaky pipe.  
Apparently, City records indicate that the water mains in the 
area were supposed to have been inspected and tested following 
the construction project.  However, when asked about these 
records, Mr. Scheller testified that inspection and testing were 
never done.  
Assuming 
MMSD 
can 
prove that 
the 1992-93 
construction 
project 
damaged 
the 
water 
main 
and 
that 
a 
reasonable 
inspection 
after 
the 
construction 
project 
was 
completed would have revealed the defect in the pipe,29 we 
                                                 
29 Given Mr. Chisholm's testimony that the fracture in the 
water main existed from .8 to 2.6 years, there is a dispute over 
whether any defect would be observable immediately after the 
1993 construction project was completed.   
No. 
02-2961   
 
54 
 
believe there exists a disputed issue of material fact with 
regard to notice.30   
V. SUMMARY 
¶88 We hold that in order to establish a prima facie case 
for liability for a nuisance, there must be proof of the 
nuisance, proof of the underlying tortious conduct giving rise 
to the nuisance, and proof that the tortious conduct was the 
legal cause of the nuisance.  The alleged nuisance in this case 
is the City's interference with MMSD's property interest in its 
sewer.   
¶89 We conclude that under the law governing liability for 
nuisance based on intentional conduct, the pleadings and record 
do not support any claim that the City intentionally created a 
nuisance.  We conclude that the only actionable tortious act 
giving rise to the nuisance in this case is the City's alleged 
negligence in failing to repair its leaky water main before it 
burst.  We reaffirm our existing case law that when a nuisance 
is predicated on negligence, all the usual rules and defenses 
applicable to negligence claims apply.  Thus, when a nuisance is 
predicated on a negligent failure to act, there must be proof 
                                                 
30 The City also argues that we should deny liability based 
on public policy factors.  In Physicians Plus, 254 Wis. 2d 77, 
¶¶44, 49, we noted that liability could be denied in an 
appropriate nuisance case based on the traditional six public 
policy factors.  The City's one-page public policy argument does 
not identify which public policy factors support denying 
liability.  An appellate court need not consider arguments that 
are inadequately briefed.  State v. Pettit, 171 Wis. 2d 627, 
646-47, 492 N.W.2d 633 (Ct. App. 1992).  Thus, we do not address 
this argument.   
No. 
02-2961   
 
55 
 
that the defendant's conduct constituted actionable negligence, 
including proof of notice, regardless of whether the alleged 
nuisance is public or private.  
¶90 Moreover, 
we 
hold 
that 
under 
§ 893.80(4), 
and 
Wisconsin's immunity jurisprudence since Holytz, a municipality 
may be immune from nuisance suits depending on the nature of the 
tortious acts giving rise to the nuisance.  A municipality is 
immune from suit for nuisance if the nuisance is predicated on 
negligent acts that are discretionary in nature.  A municipality 
does not enjoy immunity from suit for nuisance when the 
underlying tortious conduct is negligence and the negligence is 
comprised of acts performed pursuant to a ministerial duty.   
¶91 Decisions 
concerning 
the 
adoption, 
design, 
and 
implementation of a public works system are discretionary, 
legislative decisions for which a municipality enjoys immunity.  
Thus, the City is immune from suit relating to its decisions 
regarding the adoption of a waterworks system, the selection of 
the specific type of pipe, the placement of the pipe in the 
ground, and the continued existence of such pipe.  In contrast, 
the City may be liable for its negligence in failing to repair 
the leaky water main.  However, since there exists a material 
issue of fact as to whether the City had notice of the leaking 
water main, we cannot determine whether the City was under a 
ministerial duty to repair its water main prior to the break.  
Thus, we cannot determine whether the City is immune under 
§ 893.80(4) from liability predicated upon a negligent failure 
to repair the water main before it burst.   
No. 
02-2961   
 
56 
 
¶92 Finally, viewing the summary judgment materials in a 
light most favorable to MMSD, we conclude that there are at 
least two disputed issues of material fact.  In addition to the 
disputed issue of fact regarding whether the City had notice of 
the leaking water main prior to the break, there exists a 
disputed issue of fact as to what caused MMSD's sewer to 
collapse.  Therefore, we affirm the decision of the court of 
appeals, reversing the circuit court's grant of summary judgment 
in favor of the City.   
By the Court.—The decision of the court of appeals is 
affirmed.   
 
No.  02-2961.dtp 
 
1 
 
 
¶93 DAVID T. PROSSER, J.   (concurring).  I agree with the 
court's decision to remand this case to the circuit court, as 
directed by the court of appeals.  Milwaukee Metropolitan 
Sewerage Dist. v. City of Milwaukee, 2003 WI App 209, ¶33, 267 
Wis. 2d 688, 671 N.W.2d 346.  I also agree with the court's 
comprehensive discussion of nuisance law.  My problems with the 
majority opinion are twofold. 
¶94 First, the court's discussion of governmental immunity 
reiterates several principles of law that, in my judgment, 
depart 
from 
the 
language 
and 
legislative 
intent 
of 
Wis. Stat. § 893.80(4).  My views on this subject are stated in 
Scott v. Savers Property and Casualty Insurance Co., 2003 WI 60, 
¶¶75-82, 
262 
Wis. 2d 127, 
663 
N.W.2d 715 
(Prosser, 
J., 
dissenting), and Willow Creek Ranch L.L.C. v. Town of Shelby, 
2000 WI 56, ¶¶59-172, 235 Wis. 2d 409, 611 N.W.2d 693 (Prosser, 
J., dissenting).  The court's present opinion not only firms up 
mistaken principles but also criticizes Costas v. City of Fond 
du Lac, 24 Wis. 2d 409, 129 N.W.2d 217 (1964), a case both filed 
and decided after Holytz v. City of Milwaukee, 17 Wis. 2d 26, 
115 N.W.2d 618 (1962), and after enactment of the predecessor to 
Wis. Stat. § 893.80(4).  See ch. 198, Laws of 1963 (effective 
July 27, 1963).  When the Holytz court abrogated the principle 
of governmental immunity in 1962, and saw its decision promptly 
codified by the Wisconsin legislature, it could not have 
imagined that a successor court would assert that it was 
No.  02-2961.dtp 
 
2 
 
actually expanding immunity to cover government activities 
previously determined not to be immune. 
¶95 Second, I have trouble reconciling the discussion in 
the section on summary judgment with the discussion in the 
section on governmental immunity.  The court acknowledges that 
"a municipality may be liable for a nuisance founded upon 
negligent acts."  Majority op., ¶59.  But then it states: "The 
only act for which the City may be potentially liable is its 
failure to repair the leaking water main."  Id., ¶61.  "The 
question [is] whether the City was under a ministerial duty to 
repair the leaking main before it broke," a duty "absolute, 
certain and imperative, involving merely the performance of a 
specific task when the law imposes, prescribes and defines the 
time, mode and occasion for its performance with such certainty 
that nothing remains for judgment or discretion."  Id. (quoting 
Lister v. Bd. of Regents, 72 Wis. 2d 282, 301, 240 N.W.2d 610 
(1976)).  As a practical matter, this formulation is so narrow 
that it appears to decide the case. 
¶96 Because of these concerns, I respectfully concur. 
 
 
No.  02-2961.dtp 
 
 
 
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