Steps in the civil litigation process

Professional engineers and other experts provide better services to civil litigation lawyers, the judge and the jury when they have some understanding of the civil litigation process.

Counsel, in particular, benefits when they retain an expert who is well informed about the process and their role in it.  Many experts are limited in this knowledge.  I know I was when I started practicing forensic engineering a number of years ago.

Expert witnesses play an important role in modern litigation (Ref. Stockwood, Q.C.).  The educational component of the contribution engineers provide to the civil litigation process is invaluable (Dunphy, Q.C.).  Experts fulfill this role better when they understand the process.

The purpose of this posting is to enlighten experts on the nature of the civil litigation process.  More detailed information can be had from David Stockwood’s easily read text, Civil Litigation, 5th edition.  Every expert should be given a copy of this text by retaining counsel.

Because of the sequential nature of the process, it is possible for an expert witness to start serving at almost any point during the process.  But, of course, beneficial to all concerned to be commissioned at the start of a lawsuit.  Joining the proceedings after they have begun requires the expert to “catch up” (ASCE Guidelines).  And risks counsel finding himself “out on a limb” with a weak case technically.

The following is what I’ve come to understand about the civil litigation process after a literature and internet search and conferring with acquaintances in law.  There is some comment in the following item on the role of professional engineers at different stages in civil litigation.  I added these comments to provide a little technical context.

The civil litigation process involves the following main steps:

  • Pre-Civil Litigation
  • Counsel’s First Meeting With Client
  • Pleadings (Notice of Claim, Statement of Claim, Statement of Defense, Affidavit of Documents)
  • Discovery
  • Alternate Dispute Resolution (ADR) (Negotiation, Mediation, Arbitration)
  • Settlement Conference
  • Trial Date Assignment Conference
  • Trial

1. Pre-Civil Litigation

This, in a sense, is the first step in the litigation process – trying to avoid a lawsuit.

All reasonable efforts are made at this stage to resolve a dispute with someone.  This would include talking with them and sending letters.  Counsel may be retained who would send letters as well.

If, in spite of the letters, the person who believes their property has been damaged, or believes they have been injured through negligence, if they still have not come to an agreement to resolve the conflict then the next step can be taken and a lawyer consulted and litigation possibly begun.

At this stage, professional engineers occasionally receive enquiring telephone calls in which a dispute is described and the engineer’s comments sought on the technical issues in the problem.

2. Counsel’s First Meeting With Client

The purpose of the lawyer and the client’s first meeting is so counsel can gather information to help him assess the merits of the case and decide if he should take it.  The lawyer will also be representing his firm to the client during the meeting.

In meeting with the client the lawyer obtains information from:

  • the client’s description of the problem and the damages the client believes he has incurred,
  • documents provided by the client,
  • knowledge of witnesses,
  • answers to questions raised by the lawyer, and
  • the lawyer’s past experience of similar matters.

One of several important considerations covered by the meeting and the lawyer’s review of the facts is the need for an expert on the case.  An expert can make or break a case (Stockwood, Q.C.) and if thought to be necessary should be chosen carefully and retained early – even if only briefly in the event counsel decides not to take the case.

If the technical issues are complex – and a professional engineer can certainly help determine these issues, their complexity, and an order of magnitude of investigative costs – the monetary claim for damages likely to be substantial, and the lawsuit quite lengthy then this will affect the client’s litigation costs.  The client’s ability to bear these costs is important information in counsel’s decision on whether or not to take the case.

If the lawyer does decide to take the case, the next four steps in the civil litigation process are collectively known as the Pleadings – the Notice of Claim, the Statement of Claim, the Statement of Defense, and the Affidavit of Documents..

3. Notice of Claim

Civil litigation officially begins with the lawyer preparing and filing a Notice of Claim, a document that introduces the litigation.  It describes the parties and the fact that the plaintiff is starting a legal action in court against a defendant or a group of defendants.  The Notice of Claim is typically attached to the Statement of Claim, the documents filed with the court, and then served on the defendants.

A professional engineer could have a particularly critical role at this stage in litigation.  The engineer could contribute to counsel’s assessment of the strength of a case and whether or not to actually begin a lawsuit by filing a Notice of Claim.

4. Statement of Claim

The Statement of Claim is more particular.  It is a document that further describes the parties and defines their relationship(s) with each other.  It is a listing of the facts both legal and technical.  In construction and engineering claims, the parties oftentimes have a formal contract.  In general negligence claims, the parties are often in proximity such that one owes the other a legal duty – to do or not do something.

Counsel sets out the disputed issues and the claims the wronged party, the plaintiff, is making against the defendant.  The claims would include, for example, the relief sought – what the plaintiff wants the court to award.  This can be very general, such as claiming damages, interest and costs, and does not usually state exact dollar figures.

The Statement of Claim is served on the defendant by the plaintiff, typically through a process server who is engaged to personally hand-deliver the document to the defendant.  The process server swears an affidavit that this was done.

5. Statement of Defense

The defendant’s lawyer prepares a Statement of Defense that replies to each claim and allegation made by the plaintiff.  The defendant may file counter-claims and also claims against third parties with the court.  The document sets out the legal and technical facts and the legal grounds that the defense is relying on in their reply to the plaintiff and in their claims and allegations against the plaintiff and third parties.

The role of a professional engineer retained by the defence at this stage would be similar to that of a professional engineer for the plaintiff:

Amendments to both the Statement of Claim and the Statement of Defence may be issued by the respective parties after their initial claims are made.

Once the last of the Statements of Claim and Defence and amendments have been filed – one for each party, the pleadings are said to be closed.

The parties involved in the dispute may now exchange informal letters to try and come to an agreement and settle their differences before proceeding with a number of other steps.  In a sense, the clock starts ticking at this point in the countdown to going to trial.

6. Affidavit of Documents

If the matter is not settled, the next step is disclosure of each party’s relevant documents.  This is done by means of an Affidavit of Documents that all parties prepare, swear, serve and file with the court.  A party must produce in its affidavit all documents and electronic information it has in its possession or control relevant to the matters in issue.

Note: Ideally, all forensic engineering investigations of the cause of the problem would be complete by this stage.  These would be the separate investigations commissioned by the different parties to the dispute.  Some would be quite simple like reviewing the work of other engineers.  Other investigations might be quite complex like determining the cause of the problem that initiated the claim for damages in the first place.  The resulting technical data would have provided the basis for well informed and well thought out pleadings.

7. Discovery

Discovery, in general, is a step in the civil litigation process whereby information is obtained from the opposing parties or other witnesses.

At the discovery stage all engineering investigation is complete, all evidence, engineering data, and testimony that any party may offer at trial is known and can be fully examined by all other parties.  The cause of the engineering failure, poor structural performance, or personal injury/fatal accident has been determined.

By reviewing the total body of evidence, the parties and their counsel are able to assess the strength of their respective positions if the action proceeds to trial.  This review and assessment is carried out in three ways:

  • Discoveries (ask questions)
  • Interrogatories (submit written questions)
  • Undertakings  (agree/undertake to provide information, data and physical evidence later)

Prior to discovery in some jurisdictions, questions can be asked of an expert in writing by opposing parties.  In Nova Scotia this is Rule 55 of the Civil Procedure Rules.  These questions are delivered through counsel to the expert and must be responded to within a stipulated period of time.  This procedure was developed to limit the discovery of experts.

Discoveries are oral question-and-answer sessions under oath where each party’s counsel poses detailed questions to the other party’s witness(s), including engineering experts, about the opinions and testimony they will offer at trial.  A discovery is formal and similar to trial except it is not held in a court before a judge.  The sessions are recorded by a court reporter who transcribes the proceedings which can be used later at trial.

Interrogatories are written questions from opposing parties to engineering experts by agreement which were not asked at discovery.  The questions must be answered within a prescribed period of time.

Undertakings are agreements by the engineering expert who is answering questions to provide answers later or copies of documents or other material.  This would be information that the engineer could not readily provide to the opposing party at the time.  The information may consist of paper documents, electronic data and physical evidence.  The engineer undertakes to provide the information within an agreed period of time.

8. Alternate Dispute Resolution (ADR)

ADR is a step that can be carried out at any stage in civil litigation – even before an action is filed.  It’s a way of resolving disputes without going to court.  In some areas, over 90% of lawsuits involving the built environment settle before going to trial.

Once an action is commenced, ADR can still occur at any point but is mainly used after document production and discoveries have taken place. At that point, each side is more fully aware of the other side’s case and has more information to assess the merits of the case, the strengths and weaknesses for both parties, and the likely outcome if proceeding through to trial. As such, ADR becomes relevant as the parties know better where each side stands.

There are different forms of ADR but the following are common and particularly relevant to civil litigation.

  • Negotiation
  • Mediation
  • Arbitration

An engineering expert’s services are generally the same regardless of the ADR method selected by the client.

In Negotiation, participation is voluntary and there is usually no third party who facilitates the process or suggests a solution.

If an individual or a firm has a disagreement with another they may get together to discuss the problem and reach a mutual agreement.  This way the parties can work out a solution that best meets the needs and interests of all parties.

In some cases individual parties may also prefer to hire a lawyer or a counselor who has the expertise to help a firm to negotiate or who can negotiate on behalf of the firm.

In Mediation, there is a trained, neutral third party, a mediator, who facilitates the resolution process (and may even suggest a solution) but does not impose a solution on the parties, unlike judges.  Mediation often leads to resolutions that are tailored to the needs of all parties.  The process is informal and completely confidential.  As a result parties may speak more openly than in court.

In Arbitration, participation is typically voluntary and there is a third party who, as a private judge, imposes a resolution.  At an arbitration hearing, a party to a dispute may have a representative speak on their behalf.

Arbitration may occur when parties have a dispute that they cannot resolve themselves and agree to refer the matter to arbitrators.  Arbitration can also occur because parties to contracts agree that any future dispute concerning an agreement will be resolved by arbitration.

Arbitrators are often people who are experts in a specific area of the law or a particular industry, for example, the professions, pharmacy and engineering.

The arbitrator makes a decision based on the facts, any contracts between the parties in dispute, and the applicable laws.  The arbitrator will explain how the decision was reached.

If the applicable law allows, parties can decide in advance whether the arbitrator’s decision will be final and binding or whether it can be submitted to a court for review if a party disagrees with the decision.

9. Settlement Conference

If ADR is not tried or is unsuccessful then lawyers for the parties meet and confer with a judge to decide if a settlement is possible with his assistance.  By this step in the civil litigation process the parties will be ready to go to trial.  They will have the documents that they will be relying on, reports from professional engineers and other experts, and information from discovery.

The lawyers, in advance of the Settlement Conference, send the judge a brief summary of their arguments and any relevant documents.

At the conference the judge will listen to the lawyers and try to achieve a settlement.  The judge will sometimes give an opinion on how they would decide the case if they heard it at trial.  However, the conference judge cannot force a settlement and would not officiate at the trial because of their role in the settlement conference.

10. Trial Date Assignment Conference

Once the discovery has taken place, any party can ask for a trial date.  This is done with a formal notice to the court for a Trial Date Assignment Conference.

These conferences are predicated on formal submissions by the parties setting out:

  • how many witnesses they will have,
  • how many of these witnesses are experts,
  • the issues,
  • the general subject matter to which each witness will speak,
  • how long the trial will take and,
  • whether the trial will be judge alone or judge and jury.

The lawyers for each party attend in front of a judge during the Date Assignment Conference or confer over the telephone.  The parties to the action do not usually take part in the conference.

At the conference, the court sets a number of applicable dates:

  • the date by which all discoveries are to be completed,
  • the date by which expert reports are to be circulated,
  • the finish date,
  • the date for the trial readiness conference and,
  • the date of the trial.

11. Trial

When lawsuits occasionally reach this stage, the role of the professional engineer at trial is similar to that during discovery.  However, while discovery testimony can focus on intricate detail, trial testimony generally addresses key issues and themes.

The procedure at trial consists of a number of question-and-answer sessions on the evidence and witness testimony, similar to those during discovery, followed by closing arguments or summations.  The judge may ask questions at any time during the trial.

At the end of the trial in civil litigation, a judge studies the evidence and testimony, makes findings and arrives at a decision.  Decisions typically are issued later by the judge rather than from the bench and are given in writing.


  1. The civil litigation process – an overview.  Heydary Hamilton, Ontario
  2. ASCE Guidelines for Failure Investigation 1989
  3. ASCE Guidelines for Forensic Engineering Practice 2003
  4. P.E.I. legal information, Going to Court: Civil Trial Procedure
  5. Community Legal Information Association of Prince Edward Island, Inc. ISBN 978-1-894267-51-9 2003
  6. Personal communication, 2011, Gavin Giles Q.C., McInnes Cooper, Halifax
  7. Personal communication, 2011, Michael Dunphy Q.C. and Ashley Dunn, Cox Palmer, Halifax
  8. Personal communication, 2011, Jean McKenna, Partner, Ritch Durnford, Halifax
  9. Walker, Janet, gen. ed., Civil Litigation, 6th edition, 2005, Emond Montgomery Publications Ltd., Toronto
  10. Stockwood, Q.C., David, Civil Litigation: A Practical Handbook, 5th edition, 2004, Thomson Carswell, Toronto
  11. Flowcharts summarizing the processes under the Rules of Civil Procedure, Ontario, January 1, 2010 (Google)




Civil procedure Rule 55 will improve expert’s reports and forensic engineering investigation

Expert’s reports can be written better and there are resources available to enable them to do this.  This need will be driven in part by civil procedure rules such as Rule 55 in Nova Scotia, Canada.  These rules require an objective presentation of opinion to the court and a statement of the certainty with which these opinions are held.

Rule 55 will promote better report writing and forensic engineering investigation

When I first prepared a report two years ago according to the requirements of Rule 55 I was struck by the potential for this rule to promote better expert report writing,  And, by extension, better, more thorough forensic engineering investigation.  You can’t write a good report unless you’ve carried out a good investigation.  The rule reduces reliance on discovery in the civil litigation process and increases reliance on experts’ reports, and, by inference, sets a high standard for the reports.

Reason for poorly written expert reports – but no excuses 

I have been troubled by the poor composition, unsupported statements, and leaps of faith in drawing conclusions – some that would scare a tightrope walker, that I’ve seen in some experts’ reports.  No surprise given that we engineers and scientists like to measure things, crunch numbers and analyse data.  We are not wordsmiths by nature.  But this doesn’t relieve us of the responsibility to communicate our findings in simple English and to do it effectively.

Not to fault the techncal expert too much.  We are not educated and trained to communicate with lay people.  We then practice for several decades communicating for the most part with other technical types – no simple English skills needed; jargon only spoken here.  Finally, we are retained in later years for our extensive technical knowledge and experience and presented as experts to the courts – only to find we can’t write and speak simple English to civil litigation lawyers, judges, and juries.

Nor is the civil litigation lawyer – the wordsmith in the process, relieved of a responsibility to confirm that the expert they retain can present their findings in well written, laymen’s terms.  That they can write so judges and juries can understand.  The role of the expert in the judicial system is to interpret and explain technical material.  One role of the lawyer is ensuring that he or she understands the report before it goes forward.  The lawyer is like a gate keeper.

Being technical is neither an excuse nor the justification for poor writing.  The inability to write well is a career-limiting short-coming (see Ref. 1) – and a potential embarrassment to lawyers, judges, and juries, not to mention the engineer and the scientist.

Source of experience leading to my views on the state of expert report writing

My experience leading to these views has been with engineering and legal firms ranging in size from sole practicioners to 50 to 75 staff.  Firms located in eastern and western Canada, and overseas in Australia, the U.K., and the Caribbean.

However, my colleague, Gary Bartlett, noted that he experienced a culture in much larger organizations – 200 staff, that encouraged and required good writing skills, and they achieved this (1).  Gary was an electrical engineer with the Canadian air force – air crew, for about 12 years then with the aerospace industry for at least another 25 years.  He still writes reports for the industry.

So, while there is a problem out there, the character and extent of it varies.  It behooves the lawyer in selecting an expert to learn a little something about where his expert is coming from.  I plan to publish an item in future on how to find an expert and what to look for.

Sources for expert report writers

CDs and books

I was prompted to write this item on receiving the latest edition of a newsletter from Expert Communications, Dallas, Texas, a few days ago.  This firm provides expert witness training tools and other services for experts.

The newsletter announced the availability of a CD on report writing entitled, Expert Report Writing: Effective and Defensible.  The CD is an hour-long teleseminar of a discussion between Rosalie Hamiliton of Expert Communications and Steven Babitsky, president of SEAK, Inc.  SEAK also provides services to experts.

Steven is formerly a trial attorney and a co-author of Writing and Defending Your Expert Report.  This book is one of the best I’ve read and studied on the subject.  Every expert should be given a copy by their retaining counsel.

Rosalie told me last Thursday that If you have Steven’s book you don’t need the CD, although they do complement one another to some extent.  But, she says – and I agree, that if you don’t have time to read a book – and many of us don’t these days – and actually like to get your education via oral and video presentations, then the CD will provide some insight into this important topic of report writing – and possibly contain a zinger from Steven Babitsky.

Critical thinking course

Talking about oral presentations, one of the most valuable experiences I’ve had in recent years, with respect to my practice in forensic engineerng investigation and the accompanying report writing, was to take a course in critical thinking.

This was an intensive, year-long, two, 1.5 hour lectures a week, course given by Professor Chris MacDonald at Saint Mary’s University in Halifax (Chris is now at Ryerson University in Toronto).  There was considerable emphasis in the course on looking critically at the basis of statements made to us and that we make; What’s the statement founded on?  What are you personally saying and basing your statement on?  These are critical questions for an expert to keep in mind when writing a report.

(You might be interested in Professor MacDonald’s blog on business ethics and behaviour at  He’s had it up for over six years – and it’s well written.  It’s been rated one of the most influencial business blogs a number of times since he put it up)

The importance of instruction in critical thinking can be gathered from the fact that hundreds of first year students at Saint Mary’s and other universities are required or encouraged to take this course.  The course was given by three different professors the year I took it.  My class had about 200 students.

Experts, regardless of how experienced, well known, and long in the tooth they might be would benefit from a course like this – and their expert reports would be better for it.

But, like reading books, not everyone can take time out to take courses at a university.  I’m beginning to think that sources like those at can help solve that problem.

This firm offers several hundred courses on DVD on a range of topics including critical thinking, reasoning, and writing.  The presentations are good and reasonably priced.  You receive a synopsis of the course with the DVD if you still want to do some reading.  A transcript of the lectures can also be purchased.  Some of the courses are interactive.  I have three of their courses on reasoning and writing.

Arguing and report writing

Gaining some understanding of Toulmin logic would also benefit those of us writing expert reports.  I see it as a practical logic as opposed to a formal logic.  Toulmin advocates – analogous with existing practice in law – a procedural rather than a formal notion of validity.  He outlines a way that assertions and opinions can be rationally justified.

His text, The Uses of Argument, is a hard read because of the terminology and style of writing in vogue in the U.K. in the 1950s when he first published his ideas.  But, fortunately, you can go on-line and view graphical representations of his ideas which I thought were quite good.  There are also courses and lectures on his methods in simple English.  The illustrations will remind experts in writing their reports of the importance of ensuring their statements are well founded.

There’s no shortage of sources on writing better expert reports

There’s no shortage of guidance and no excuse for not writing better expert reports.  This will come about driven by the high standards required by civil procedure rules like Rule 55 in Nova Scotia.  Rules like this will out the poor writers.


  1. Personal communication. Gary Bartlett, P.Eng., VP Engineering, (ret’d), IMP Aerospace, Halifax, Nova Scotia, Canada
  2. Expert Communications, Dallas, Texas
  3. SEAK, Inc., United States
  4. Toulmin, Stephen E., The uses of argument, updated edition, 2003, Cambridge

In the beginning there was civil engineering

In the beginning there was civil engineering.  Well, possibly shortly after military engineering.  And from civil engineering came forth other engineering disciplines.  And society saw that this was good.

Including, good for civil litigation lawyers and insurance claims managers – good in the wide selection of engineering expertise available to a forensic engineer investigating the cause of a client’s problem.

I’ve written this item to introduce you to some of the different engineering specialties.  These are listed below.  Lists can be boring so I’ve added a little history and my take on how some specialities got started.

Society has been “engineered” for 1,000s of years

Engineering has contributed to the development of society since the beginning of human existence.  Back when humans started to give up a nomadic way of life, settling down, and erecting more permanent shelters – structures, as in built-environment.  Civil engineering would have developed as the built environment developed.

I’m certain that military engineering evolved at the same time considering how difficult societies can be with one another.

Some literature indicates that the earliest practice of civil engineering may have begun between 4,000 and 2,000 BC in ancient Egypt and ancient Mesopotamia (ancient Iraq). Construction of the pyramids in Egypt (circa 2,700 – 2,500) might be considered the first instances of the construction of large structures.

Also, the manner in which the blocks in the pyramids were fitted together demonstrated an early appreciation of a very basic and important principle in geotechnical and foundation engineering. The beginning of geotechnical engineering?

The Romans developed civil structures throughout their empire (circa 2,700 BC – 410 AD) including aqueducts, insulae (a kind of urban apartment building), harbours, bridges, dams, and roads.

(I must confess, I don’t know what was happening in Asia and other parts of the world. For certain, the built environmennt and civil engineering were developing in areas other than in Europe)

The “first” civil engineer

The term, “civil engineering”, was coined in the 18th century to incorporate all things civil as opposed to military engineering.

The first self-proclaimed civil engineer was John Smeaton who constructed the Eddystone Lighthouse in Great Britain.  In 1771 he and some of his colleagues formed the Smeatonian Society of Civil Engineers.  In 1818 the Institution of Civil Engineers was formed in Great Britain essentially formally recognizing civil engineering as a profession (but, I’ve seen some information about the formation of a professional body in France somewhat earlier).

Evidence of the modern practice of civil engineering

Modern practice in civil engineering and its specialties can be seen today in the development of Dartmouth Crossing outside Halifax, Nova Scotia, Canada.

A natural environment has been turned into a built environment almost overnight. A built environment that includes:

  • Engineered single and multistory retail, residential (hotel), and service buildings,
  • Roads,
  • Small dams,
  • Small bridges,
  • Structural fills of soil and rock,
  • Deep rock cuts,
  • Storm water and domestic sewage collection and treatment systems,
  • Water supply and distribution systems, and,
  • Electrical power distribution systems.

Civil engineering takes place today on all levels of society. In the private sector, from individual home owners to international companies. In the public sector, from municipal governments to national governments.

Where did the different engineering disciplines come from?

Today there is a long list of specialized areas in civil engineering to serve and provide for the built environment.  They can all be called on in forensic engineering investigation to determine the cause of a failure in the built environment.

Where did these specialized engineering fields come from?  They developed as the needs of society developed.

Computer engineering, an easy example to understand, developed and came to be recognized as a field of study as computers developed in the last 50 to 60 years.

Another, fairly easy example, is structural engineering – for certain, developed if not named 1,000s of years ago, because structures had to be held up somehow.  Structural engineering provides for the support of structures.  There are no sky hooks.

There was technology before today’s technology-saturated age. Think industrial revolution, a time when technological development would have been as intense for the time as technological development is today.

It’s easy to understand mechanical engineering and electrical engineering splitting off from civil engineering during the industrial revolution and named as such.  Chemical engineering might not have been too far behind applying the principles of chemistry as this science developed.

Geotechnical engineering grew out of the science of soil mechanics, developed during the 1930s.  It was recognized then that everything in the built environment is supported on the ground, and that soil, rock and groundwater are construction materials that must be engineered properly.

Take a look at the following list of engineering specialties available to society and the forensic engineer to gain some appreciation of where we are today:

Some areas of civil engineering

  1. Structural engineering
  2. Foundation
  3. Geotechnical
  4. Construction
  5. Forensic
  6. Materials
  7. Mechanical
  8. Electrical
  9. Industrial
  10. Chemical
  11. Municipal
  12. Transportation
  13. Surveying
  14. Environmental
  15. Hydraulic
  16. Aeronautical
  17. Computer


  1. Encyclopedia Britannica
  2. Pears Cyclopaedia, 107 ed., 1998
  3. Blake, L. S., ed, Civil engineer’s reference book, 3rd ed, Buttherworks, 1975
  4. Chen, W. F., ed, The civil engineering handbook, CRC Press, 1995
  5. Wikipedia





Flying objects, injured people, and forensic engineering investigation

I read the report in yesterday’s Chronicle Herald about flying pieces of metal injuring four people on a popular ride in Yarmouth.

It occurs to me at this distance that this should be a fairly easy failure to investigate with a visual assessment by perhaps an experienced mechanical engineer.  For certain, to at least enable a tentative statement of cause.

This is because the surfaces from which the metal came loose are likely to be exposed to view.  And because there are likely to be other units (chairs?) in the ride apparatus that are identical with the metal still in place.  This would afford a before and after comparision of the in-place condition of the pieces of metal.  This type of comparision can yield good evidence.

(A failure in engineering occurs when something in the built environment doesn’t perform properly)

A visual assessment doesn’t sound very technical but it is always valuable and sometimes all that is necessary.  And it is an essential part of the main steps in the failure investigation process:

  • Acquisition of data
  • Analysis of data
  • Formulation of opinion

One time, I investigated the reason a piece of ice fell from a structure and struck and injured a person.  My investigation was based almost entirely on a visual assessment of the exposed surfaces of the structure.  I did this to some extent from a distance with binoculars and a camera with telescopic lens.

I also was able to compare the condition of the part of the structure involved with other unaffected parts of the structure and other structures in the area that were the same.

I analysed the data – largely taken from a visual assessment, formed my opinion, submitted my report, and, I understand, a dispute that had been ongoing for several years was resolved within a few months.

This situation with the falling ice seems very similar to the situation in Yarmouth with the flying pieces of metal.

At the very least, an initial hypothesis could be formed as to the cause of the problem based on a simple visual assessment.  This hypothesis could then be investigated by more detailed forensic engineering investigation, if this in fact is necessary.

The Nova Scotia Department of Labour are investigating and I’m certain we’ll know the answer soon enough.


American Society of Civil Engineers, Guidelines for Failure Investigation, 1989

The Chronice Herald, Thursday, August 2, 2012, page A6


Drought can cause property damage

In addition to the potentially low crop yield being reported in the local and national Canadian and U.S. press.

Reports from the Annapolis Valley in Nova Scotia, a prime agricultural area, note  the worst drought conditions in 10 years.  I spoke with one grower several weeks ago who incredulously noted that rain had not fallen on his crops in two months.  This in an area – eastern Canada, where a low pressure system goes through about every three or four days, often accompanied by rain.  We are fond of saying down here that the weather builds character.  I can just imagine what my grower is saying now, possibly unprintable.

Forensic engineers consider the effects of drought in some investigations.

Effects of drought

Foundations of buildings and civil engineering structures can settle or subside in drought conditions.  This can happen to both new and old structures.  This kind of settlement is in addition to that usually predicted by geotechnical engineers during foundation design.  That is, settlement due to the more normal loads on a structure – see the item published July 10, 2012 for comment describing more normal design loads.

(Geotechnical engineers investigate the physical properties of soils and rocks and advise design engineers of the effects of these properties on structures)

Foundation settlement due to drought is not usually considered in engineering design when assessing the loads on a structure in eastern Canada.  This is because this type of settlement is often slight.  Also because there is seldom a scarcity of rain in eastern Canada so we seldom experience drought conditions.

But, it should be considered elsewhere in Canada and the U.S.  And in the future down east considering the possible effects of global warming on climate change as suggested by some. And maybe during the present drought.

(Engineers think of loads as something than can affect a structure and most be provided for or accommodated in design.  There is certainly an argument for considering the effects of drought as a load on a structure even if dismissed quickly most of the timel)

Is this too esoteric a matter for engineers to be concerned with – the effects of drought on conventional structures in the built environment?  I don’t think so.

Let’s not be too quick to dismiss slight foundation settlement due to drought as insignificant.  It can be very significant to transformer foundations in substations and to the foundations of free standing, un-guyed towers and to wind turbines. (Substations are components of an electrical power distribution system)

These types of structures are quite sensitive to foundation settlement.  They are sensitive to a few millimetres settlement, like, less than 5 millimetres.  Whereas more conventional structures – such as many low-rise buildings, can tolerate in the order of 25 millimetres, and some structures somewhat more than this.

How drought causes foundation problems and damage

How can drought cause foundation settlement?  It’s quite easy and the reason will take you back to your high school physics class.

A drought causes the watertable to drop.  We all know about that – think dug wells going dry.  When the watertable drops the groundwater “drains” out of the soil above.  The soil is no longer submerged below the watertable.  The recently drained, relatively dry soil above the watertable – due to the drought, is now heavier.  Think back to your high school physics and the fact that the dry unit weight of a soil is heavier than the submerged unit weight.

Relatively dry soil will settle due to its (increased) weight, due to its increased “self weight”.  Foundations on soil that is settling or subsiding will also settle – go down with the subsiding soil.  And this can be caused by drought as we saw above.

For example, the gardeners amongst us have seen the soil in a recently planted container settle over a period of days.  This is due to the self weight of the soil causing compression or settlement within the soil.  The increased self weight of a soil that is suddenly above the watertable due to a drought will have the same effect – cause the soil to compress.

Another example is the depression across the road at the former location of a construction trench that has been filled in with soil.  A lot of this depression is due to compression within the soil due to its self weight.

The same engineering principle underlies these examples as does the effects of drought.

I can easily imagine drought causing significant settlement that is greater than slight settlement, particularly with recently designed and constructed structures in areas that have not experienced drought before.

The evidence for this lies in Mexico City.  The city has been settling for years, totalling several feet in some areas and causing much damage as you can imagine.  This settlement is due to a lowering of the watertable.  The watertable was lowered when water was pumped from wells in the city over many years.

Pumping is a different kind of assault on the watertable than drought.  But the soil doesn’t care what causes the watertable to drop and its self weight to increase.  When this occurs the soil is going to settle causing greater or lesser damage to any foundations above.

The drought occurring now can conceiveably cause foundation problems.  But a forensic engineer investigating a specific problem would need to look at factors like the sensitivity of the foundation to settlement, the magnitude of the drop in the watertable, the soil, and historical records of drought in an area.

An experienced geotechnical engineer in many parts of North America will consider the effects of drought on a structure.  They might see it as a load on a structure the effects of which – increased foundation settlement, must be provided for by a design engineer.

An experienced forensic engineer will consider the effects of drought when investigating the cause of the poor performance or complete collapse/failure of a structure.