HKIE Veneree Club16 April 2014

Realizing Economic Value via Voluntary Work– A case Study of

Residential Seepage

By YL Choi 蔡宇略Hong Kong Former Senior Civil Servants

Associationand

Hong Kong Academy of Engineering Sciences

Engineering (in contrast to Military Engineering)

“the art of directing the great sources of power in nature for the use and convenience of man..”

---Economic Value

How Do Engineers Create Economic Value?

Provide new works to enable new activities. (Quantitative enhancement)

Improve existing methods of production or operation. (Quality ebhancement)

Design new types of works toopen up new types of activities. (Quantum jump)

Prerequisite of Realizing Economic Values

Investing in new infrastructure

Protection of intellectual property rights

Removing regulatory obstacles to innovation, new design or improvements

Willing acceptance of stake holders

What can Retired Engineers offer?

• Retirees = large, diversified knowledge & experience

• Fruitful engagement economic & social benefits through new design or improvement to current process

• Difficult to identify projects

• Ways & means of engaging retirees only beginning to develop (Active Aging)

Integrating Professionalism with Volunteerism

• Knowledge Identify deficiency of current practice Propose improvement Potential economic value

• Volunteerism No vested interest Public acceptance Realize economic value

• Case study—Investigation of water seepage in residential buildings

Changing Nature of Residential Seepage Problem

• Before 1970—Mainly rainwater infiltration,

• Since 1970—Leakage in water & drain pipes,

• Since 1980—Seepage under unauthorized bath/toilet,

• Since 1990—Seepage becoming significant among new buildings,

• Since 2000—Becoming wide spread.

Rapidly aggravating seepage problem

2005 2006 2007 2008 2009 2010 2011 20120

5000

10000

15000

20000

25000

30000

Cases received

Cases handled

Social & Economic Implications of Water Seepage Problem

• Adverse neighbor relation

• Leading to social segregation in housing

• Accelerate structural deterioration

• Leading to premature redevelopment of buildings

Current Practice of Investigation

• Joint Office (JO) of Buildings Department / Food Environmental Hygiene Department is vested with statutory power

• 2-stage dye tests—on drainage pipes, then on floor of bath/toilet

• Assessment criterion—visual for 1 month, test site taken as source if dye color is noted in seepage water.

Performance of Seepage Investigation by Current PracticeResults of Cases Investigated by JO up to

31/12/2012

Source identified 27,405 43%

Could not be identified 9,151 14%

Seepage ceased 27,234 43%

Total = 63,790

Source:Govt. Reply to LCQ8 of 20130320 Resolving water seepage problems

Inconsequential Effect of Administrative Improvement

• Ombudsman 2008 investigation report on JO performance—Management deficiency identified

• Staff increase of JO—2011-12 staff members: FEHD 219, BD 64 ; $35M.(Source: Reply to LegCo questions)

• Audit report 2011—In 8 recent cases, average period of inaction=44 months.

Engineering Deficiency of investigation practice is likely!

Complex Case comprising 3 seepage incidents over 8 years

• Same seepage sites.

• Seepage at 2nd Floor unit (2F): 2006-2009; 2010 January-July; 2013 January-date.

• Seepage was intermittently visible at 3rd Floor (3F) unit 2006-2013

• No sign of defect in 3F drainage, floor or wall.

• Dye tests show no leakage of pipes in 3F.

Soil Pipe Duct

Dye Test on Soil Pipe in 3F unit

Inconsistency of Dye Tests on Floor–Incident 1

• 2007 March dye test in 3A: dye noted in 2F 14 days after test. JO suspected 3F to be source according to current practice.

• Suspicion contrary to fact—3F toilet NOT used in 2007 March to June

• Retested in July 2009—NO dye noted

• Seepage dried up in September 2009.

Inconsistency of Dye Testson Floor –Incident 2

• 2010 March dye test in 3A: dye noted in 2F 10 days after test. JO alleged 3F again to be source according to current practice.

• New method showed water intruding 3F from ceiling.

• New test in June 2010—NO dye noted

• Seepage dried up in July 2010 in both units.

New Method of Finding Flow Path by Moisture Scanning

Location of Hole in DownpipeMarch 2014

Investigation of Incident 3

• Flow path identified by new method was confirmed by opening up inspection hole.

• Dye test on vertical common down-pipe confirmed leakage.

• Opening up of pipe duct located pipe leakage points precisely.

• Anomalous dye test result on floor drainage hole confirm diffusion causing false indication of dye test.

Deficiency of Dye Test--3 Levels

• Fundamental—Water tightness of test site alone is unrelated to seepage site.

• Secondary—Dye transport mechanisms > water flow

• Tertiary—Lack scientific basis of use of observable dye concentration or 1-month observation period as criteria.

Role of Professionalism in Identifying Defect of Current Practice

• Common sense 1—a dry surface cannot be seepage source. (Incident 1)

• General professional experience—Absence of visible defect indicates unlikely infiltration.

• Hydraulic expertise—Dye test result actually implies adequacy of waterproofing state. (Incidents 1 & 2)

Role of Knowledge in Improving Current Practice

• Common sense 2—Inconsistency of successive test results must indicate that certain key parameter is missing from the assessment criterion in current practice.

• Hydraulic expertise—Identifying flow path from moisture scanning results. Hence enable direct identification of source (Contrast with trial and error approach in current practice)

Economic Value of New Method

• Reduce investigation time and disturbance to residents

• Prevents steel oxidation & premature building deterioration

• Help avoid unnecessary redevelopment and indirectly help increase housing supply

Why New Method was not Discovered Earlier

• Lack of knowledge. The necessary experience is gained only over a long career.

• Economic value is not the concern of private practitioner.

• Property developers has no interest in improvement.

• JO did not recognize deficiency of current practice

• Public is ignorant.

Conclusion• Retirees possess a wide range of knowledge and

professional experience.

• Economic value of knowledge can be realized through application to improve current operational practice.

• Volunteerism provides the impetus to go through the long process and to overcome various resistances.

• It is in the public interest for Government to create an environment conducive to engage retirees in this new mode of voluntary work.

Thank you!

Y L Choi

16 April 2014