All too often we hear stories about sewage spills and overflows, causing environmental damage and costing utilities and operators large fines. Sometimes the causes are catastrophic, like hurricanes. Unfortunately most of the time the reason is human performance and equipment malfunctions.

King County in Washington state recently had to pay a $361,000 fine for spilling 235 M gallons of sewage into the Puget sound. An investigation found the causes to be inadequate maintenance, reliability issues and lack of backup equipment. There was also a lack of employee training. Besides the fine, the county has to better monitor emergency bypasses, improve the reliability of equipment and upgrade alarm features in the plant control system.

A closer look reveals an inexpensive float switch was at the core of the issue. In the past this type of switch has repeatedly clogged, jammed and failed. To keep operations going, employees would bend the rod back in place instead of replacing it. All in all direct plant damage is $35M. This is the fourth environmental excursion since 2000, a cost which is not quantified, but large.

Another example is a recent 830,000 gallon sewage release into the Grand River in Ottawa County, Michigan, due to a power outage. Six months ago a broken 45 year old pipe caused a 2 M gallon spill at the same location. Replacement cost of the pipe is $5 M, funds are not available so the utility is patching and hoping for the best.

These are just two recent cases that would have benefited from doing a root cause audit. The methodology is similar to a root cause analysis, except of course it is done before any incident, and aims to find and fix the most impactful risks.

Steps in a root cause audit

Planning for and doing an audit typically follows the following pattern:

  1. Plan the audit, determine the process flow of problems that could turn into significant issues
  2. Perform the audit and record the findings
  3. Define the significant issues (similar to causal factors in a root cause analysis)
  4. Use the Root Cause Tree to analyze each significant issue
  5. Analyze any generic causes for each root cause
  6. Develop preventive fixes
  7. Get approvals, and implement the plan

When done, take a moment to recognize the people that helped, and do not forget to celebrate! To make things easier, it is worthwhile to learn from those that came before you!

We have long experience with investigations and corrective actions that work. A new book by Paradies, Unger & Janney “TapRooT® Root Cause Analysis for Audits and Proactive Performance Improvement” has practical check lists and advice on auditing and implementing corrective action. Read more and order your personal copy here: http://www.taproot.com/store/TapRooT-and-reg-for-Audits-Book-Set.html

Per Ohstrom is Vice President of Sales at System Improvements, Inc. #TapRooT_RCA