A Six Sigma Approach to Water Savings Gopal Buchade1 S.N. Teli2 Vivek Yakkundi3 G.V. Mulgund4 1
PG Student, Saraswati College of Engineering, Kharghar, Navi Mumbai, email:
[email protected] 2 Professor, Bharati Vidyapeeth College of Engineering, Navi Mumbai, email:
[email protected] 3 Principal, Lokmanya Tilak College of Engineering, Navi Mumbai, email:
[email protected] 4 Principal, St. John College of Engineering and Management, Palghar, email:
[email protected]
Abstract: Six Sigma has been considered a powerful tool that employs for continuous improvement in company and plants. The purpose of this paper is to explore the potential of a Six Sigma approach to reducing water losses through a combination of water efficiency and leak detection on a private distribution system. This incorporates methods developed in the water industry such as water loss reduction and water demand management. The paper demonstrates that large water savings could be made through adoption of a Six Sigma approach. The approach has the potential to be applied to a wide range of situations including sites with limited technology. This case study provides a useful source for Facilities Managers involved in the management of utilities to determine suitable water saving approaches and strategies for large estates with private water distribution networks. Six Sigma methodology used for reducing process variability and drive out waste within the processes using effective application of statistical tools like DMAIC and techniques. Although there is a wider acceptance of Six Sigma in many organizations today, in this paper application of Six Sigma for water savings. This involves how the Six Sigma methodology has been used, how Six Sigma tools and techniques have been applied and how the benefits have been generated. Private water supplies, Facilities management. Key words: Six Sigma, DMAIC, Variation Water loss, Water efficiency, Water management, Facilities management, Private water suppliers. I. INTRODUCTION Imagine yourself as a head of management of a company raise yourself, what's it that your organization produces using different processes are the requirements tested? There is an increasing global awareness that water scarcity is one of the emerging issues of this century (Morais and Teixeira de Almeida, 2007). The demand for this precious commodity is continuingly escalating through increased population and changes in precipitation patterns brought on by climate change (Bates et al.2008). Effective utilization of water through the reduction of wastage either within distribution (leaks) or at the point of use (water inefficiency) remains a key problem for both developing and developed countries throughout the world (Morais and Teixeira de Almeida, 2007). Leakage from water distribution systems has been a widely research topic due to the large percentage of losses encountered even on the smallest systems. Annually the global water sector processes 32 billion cubic meters of water that is lost through leaks (Kingdom et al., 2006) accounting for 9%-43% of the nation’s total production (Lai, 1991). In addition to the physical loss of water there are other
deleterious impacts relating to energy consumption, chemical consumption potential health and environmental risks (Colombo et al., 2009) with an associated total financial of cost of US$15.6 billion (Kingdom et al., 2006). One such issue is the energy consumption associated with treating and pumping leaked water (Colombo and Karney, 2002). This is thought to account for 5-10 billion kWh of power generated a year, in the states alone (AWWA, 2003). Water hygiene issues are also associated with burst or leaks through the intrusion of contaminated groundwater. Karim et al., (2003) demonstrated that a high percentage of soils and potentially harmful pathogenic organism such as coli forms (58% and 70% of water and soil samples respectively) and faucal coli forms (detected in 43% and 50% of the water and soil samples respectively). During low pressure events on a burst line it is possible for these contaminants to be drawn in to the system. To reduce the like of failure the utilization of frameworks to support improvement initiatives is deemed critical (Oakland and Tanner, 2007). One such framework is Six Sigma which has gained recognition as a quality improvement methodology within the manufacturing and service industries (Basu, 2004). It has been applied successfully to the utilities industry (Inozu et al., 2006; Pheng and Hui, 2004) and can be used to drive sustainability initiatives (Zhang and Awasthi, 2014; Banawi and Bilec, 2014; Cherrafi et al., 2016a; Cherrafi et al., 2016b). Although other frameworks, such as lean, have been proposed to improve sustainability performance it is believed that their integration has not assisted organizations achieve peak performance, unlike that of Six Sigma (Banawi and Bilec, 2014). Our conclusions are that Six sigma is just a remote second to Lean in terms of popularity. In one research, out of the 17 surveys examined, it was attainable to estimate the percentage of organizations implementing Six Sigma based on only eight studies. The goal of the project was to streamline and standardize the establishment and maintenance of costing and designing for all business activities. II. METHODOLOGY Six Sigma as an entire will perform primarily in 3 completely different mannerisms: As a metric, management system, and methodology. As a metric, Six Sigma is a scale of how sensible a company's quality is to have "Six Sigma" quality standard, an organization should only have 3.4 DPMO. As a management system, six sigma pulls within the ideas of six sigma into a company business strategy. As a methodology, Six Sigma is represented by the Six Sigma model (GooFreshan, 2012). Six Sigma methodologies are
applicable in each manufacturing and nonmanufacturing industries. Six Sigma is defined as follows: Define–To identifies the issues measure – Gather the proper knowledge to accurately assess a problem. Analysis – Use statistical tools to properly determine the root causes of a problem. Improve – Correct the problem (not the symptom) control–puta concept in place to make positive problems stay fixed and sustain the gains. III. CASE STUDY This case study shows how the Six Sigma methodology was used to reduce variability of the selected process. “Six Sigma is an organized, parallel-meso structure to reduce variation in the organizational processes by using improvement specialists, a structured method, and performance metrics with the aim of achieving strategic objectives” (Dreachslin, J. and Lee, P. (2007)). Using a data driven improvement methodology Six Sigma aims to identify and significantly reduce operational defects and variability to improve process performance. The Six Sigma methodology that was used to guide implementation was the five phase DMAIC cycle (define, measure, analysis, improve and control) (Bergman and Klefsjo, 2003) whereby the initial problem is defined prior to the utilization of various tools to measure, analysis and seek the root causes which can be removed and controlled to ensure performance. In this case study, the process problem which was being addressed was water loss and water inefficiencies. Six Sigma tools were used alongside standard water industry approaches to aid with the measurements and analysis.
and facilities). This identified that the main goal of reducing overall water consumption could be achieved through a combination of leak reduction techniques on the main distribution system and a water demand management approach within the facilities. V. MEASUREMENT In the measure phase, a measurement system analysis (MSA) is conducted which includes the Gauge Repeatability and Reproducibility (Gauge R&R) (Raisinghani, Ette, Pierce, Cannon and Dariply, 2005). The purpose of the Gauge R&R study is to ensure that the measurement system is statistically sound. Gauge repeatability and reproducibility studies determine how much of the observed process variation is due to the measurement system variation. TABLE II: Measurement techniques at various levels of the distribution system Consumption Baseline Main feed District metered area (DMA) analysis Distribution Distribution Leg 1 Leg 2 Water efficiency audits Faci Faci Faci lity lity2 lity3 1
Faci lity4
Distributi on Leg 3 Faci lity5
Facili ty6
IV. DEFINE The charter of the Six Sigma project was developed by the Water Services Manager. The business case was based on the fact that water demand was on the verge of exceeding supply across MPC, despite efforts to optimize water processes to maximize the inputs (Cairns et al., 2012). The situation had led to excessive chemical consumption, increased pumping costs and a twofold increase in operator overtime. Due to the age of the infrastructure, water demand was likely to be excessive as a result of large leaks and inefficient water fittings. Table I: SPIOC (Supplier, Input, Process, Output, and Customer) Supplier
Inputs
Process
Outputs
Water services
Portable water
Pumping of water Main feeddistr ibution facilities
Supplied water
Customer s MPC inhabitant s
The process improvement tool SIPOC; suppliers, inputs, process, outputs, and customers Table I was used to define the system to allow for better targeting of resources. The SIPOC revealed that the process of water delivery could be split into three distinct levels within the system (main feed, distribution
An array of measurement techniques was formulated to cover each of these separate areas and provide a holistic picture of water consumption, losses and inefficiencies, taking into account the limited technology onsite Table 2. The first stage of the measurement process involved determining the base line consumption figures for the site on a day-to-day basis. This included overall consumption for the site Table 2 and minimum night flow (MNF). MNF measurements provide a better indication of leakage on the system compared to daily readings since actual demand is at its lowest during night time (0100hrs-0300hrs) making the leakage component the highest percentage of flow (Morrison, 2004). The second stage of the measuring process involved the setting up and monitoring of District Metered Areas (DMAs). A DMA is specifically defined area of a distribution system in which the quantities of water entering and leaving the district can be metered. Flow monitoring (particularly MNF) can be used to calculate the level of leakage within a district providing an indication of levels of leakage within different areas and where resources should be focused (Morrison, 2004). Flow measurements from the final meters on the DMAs provided an indication of consumption within individual facilities and could be fed in to the final stage Water Efficiency Audit. The audit used a standardized form to determine if actual consumption was in line with expected
consumption based on staffing levels and fittings within the facility (Affinity Water, 2010). Analysis of night time readings supported this by providing an indication of leaks within individual facilities VI. ANALYSIS Analysis using process capability analysis, the DPMO level and sigma level of the fresh water consumption were known. Results from the DMA analysis illustrated that the high site consumption was the result of one particularly problematic distribution leg comprising 4 DMAs. DMA analysis of this leg Table III showed that 77.28% of the total water was lost to leakage, accounting for 23% of total consumption for the site. The worst areas were DMA 2 and DMA 4 which lost roughly 188m3and 24 m3 a day respectively. DMA 3 and 1 experienced comparatively lower calculated losses at 1 m3and 2 m3 respectively. Table III: DMA analysis figures (January 2016) Expected consumption (L) DMA 278,137 1 DMA 263,742 2 DMA 14,484 3 DMA 58,484 4
based off mean daily consumption Actual(L)
Losses(L)
Losses (%)
276,616
1,521
0.55
75,256
188,486
71.47
13,419
1,065
7.35
34,602
23,882
40.83
Total 214,954 77.28% In addition to the high percentage of water loss through leaks on this leg the water efficiency audits revealed that a number of metered facilities experienced excessive consumption Table IV totaling 10 a m3day between 2-3. In all cases, there was significant flow (up to 150 liters hour) during the periods of 0100-0300hrs. Water efficiency audits revealed that it was a faulty urinal flow control device at the facilities with meters 1, 37 and 40, whilst an external water leak was the cause of high water consumption at meter 6. Table IV: Water Efficiency Analysis (August 2016) Expected daily Consum ption (L) Meter 1 Meter 6 Meter 37 Meter 40
VII. IMPROVE The optimal solutions for reducing mean and variation are determined and confirmed in the improve phase. The gains from the improve phase are immediate and are corrective in nature. Specific problems identified during analysis are attended to in the improve phase. Corrective action was prioritized as per. Leaks were located using a combination of visual inspections of the lines, and valve pits in dry conditions and step analysis. Faulty urinal flow monitors were corrected, monitored and replaced if broken. In terms of DMA analysis Table V this lead to a 251m3reduction in consumption along the leg and a drop in the water losses from 77.28% to 17.01%. The greatest improvements were realized following work to DMA 2 and DMA 4. Table V: DMA analysis December 2016
DMA 1 DMA 2 DMA 3 DMA 4
Expected consumption (L) 28354 13481 6417 3867
Actual (L)
Losses (L)
Losses (%)
25432 11951 6180 3723 Total
2912 1559 229 154 4824
10.27 11.03 3.57 3.95 17.01
Following repairs to the main potable line, buildingwater efficiency was targeted. Night time meter readings revealed either leaks meter side of the building or inefficient water fittings the most common fault was with urinal control devices. These were adjusted where possible and replaced leading to large water efficiency savings within buildings Table VI. Table VI. Water Efficiency Analysis December 2016 Mean daily consumption End (L)
Meter 1 Meter 6 Meter 37 Meter 40
349 184 625 187
Water consumption per person per day(L) 11 23 19 17
Daily Water Saving (L) 4258 2926 2998 2618
Water consumptio n per person per day(L) 138
Potential Losses
1600
Mean daily consumpt ion (L) 4637
400
3125
87
2740
From the start of the trials in April 2016 there was a 39% decrease in mean monthly water consumption from 962m3/day to 584m3/day in July 2016 (Fig 4). Over the course of a year, this would have provided a saving of 137 million liters. A 39.3% reduction in annual consumption from 2016 compared to 2015 led to the lowest consumption figures on record and the internal water efficiency targets for 2020.
1600
3615
105
2021
VIII. CONTROL
500
2827
76
2730
3025
Minimum night flow was used as the main control measurement. Investigations were initiated in the instances where water consumption rose above 22.5m3/h in the form of further DMA analysis and water efficiency audits around MPC. Following the initial investigations which realized
issues with the urinal control systems water efficiency training was provided to cleaning staff. This proved a successful control measure which helped identify several faulty urinals and leaks.
IX. CONCLUSION This paper has following conclusion are mentioned below. • Six Sigma methodology can been successfully utilized to reduced water loss in a Private Water Supply Setting to meet environmental quality targets. • The underlying principals were successfully applied to both supply side (leakage) and demand side (water efficiency audits) to achieve a 39% reduction in annual consumption. • The adoption of a systematic approach to reducing water consumption can aid in providing an effective, low cost solution even on sites with limited technology. As water conservation begins to play a more influential role within organizations, industry will naturally have to adapt to support these new requirements. REFERENCES 1.
Alessandro Laureani, Lean Six Sigma in the service industry, Advanced topic in Applied Operations Mangement. 2. Ansari A., Diane Lockwood, Emil Thies, BatoulModarress, and Jessie Nino, Application of Six-Sigma in finance: a case study, Journal of Case Research in Business and Economics. 3. AWWA Water Loss Control Committee. (2003). Applying worldwide BMPs in water loss control Journal of AWWA, 95, 65-79. 4. Banawi, A., & Bilec, M.M. (2014). A Framework to Improve Construction Processes: Integrating Lean, Green and Six Sigma. International Journal of Construction Management,14,45-55. 5. Boyer, K. K. (1996). “An assessment of managerial commitment to lean production.” International Journal of Operation Management, 16 (9), pp. 48-59. 6. Gaikwad L.M., Sunnapwar Vivek, Teli S.N. (2016) “Adaption of TRIZ method for problem solving: a case study” International Journal of Six Sigma and Competitive Advantage,Vol. 10(2), pp 146 -155. 7. Buchade G.V., Teli S.N. (2017). “Review of Lean Six Sigma Implementation.”International Journal of Scientific Engineering and Research, Vol. 8 (3), pp. 234-240. 8. Buchade G. V., Teli S.N., Metri B. (2017), “Application of Six Sigma for Reduction of Fresh Water Consumption”, 11th International conference ISDSI, IIM Trichy. 9. Cairns, R., Sharp, E., Maher, K.,&Jefferson, B. (2012). Scope for potential energy savings in the flocculation process.Water and Environment Journal,26,319-323. 10. Colombo,A.F.,& Karney, B.W. (2002). Energy and costs of leaks: towards a comprehensive picture.Journal of Water Resources Planning and Management,128,441-450. 11. Dreachslin, J. and Lee, P. (2007), “Applying Six Sigma and DMAIC to diversity initiatives”, Journal of Healthcare Management. Vol.52 No. 6, pp. 361-367.
12. Elliot Boldt and Matthew Franchetti. “Total Sustainability Assessments for Manufacturing Operations Using the Lean Six Sigma Approach.”Science Journal of Environmental Engineering Research, ISSN:2276-7495, pp.201. 13. Gupta, R., Nair, A. G. R., & Ormsbee, L. (2016). Leakage as Pressure-Driven Demand in Design of Water Distribution Networks. Journal of Water Resources Planning and Management, 142, 1-14. 14. Henderson, K.M., and Evans, J.R. (2000). “Successful implementation of Six Sigma: Benchmarking: General electric company.” An International Journal, 7(4), pp.260–282. 15. Jadhav S. B., Jadhav G.P., Teli S.N. (2014) “Steel Industries and Six Sigma” International Journal of Scientific & Engineering Research, Vol. 5(12), pp. 53-60. 16. Kapur, K.C., andFeng, Q. (2005). “Integrated optimisation models and strategies for the improvement of the Six Sigma process.” International Journal of Six Sigma and Competitive Advantage, 1(2), pp 210–228. 17. Kaushik, P. and Khanduja, D. (2008), “DM make up water reduction in thermal power plants using Six Sigma DMAIC methodology”, Journal of Scientific and Industrial Research, Vol. 67 No. 1, pp. 36-42. 18. Teli S.N., Majali V.S., Bhushi U.M. (2013) “Assessment of Cost of Poor Quality Using Knowledge based System” International Journal of Engineering Research &Technology,Vol. 2(2), pp 1-10. 19. Teli S.N., Gaikwad L.M.,Majali V.S., Bhushi U.M. (2015)”An Application of Six Sigma to Reduce Supplier Quality Cost”,J. of The Institution of Engineers (India): Series C, Vol. 97(1), pp 93-107. 20. Teli S.N. Majali V.S. BhushiU.M., Gaikwad L.M., (2014)“Assessment of Supplier Quality Cost in Automobile Industry” Int. Journal of Quality Engineering and Technology, Vol.4(1), pp.1-20. 21. Teli S.N., V.S. Majali, U.M. Bhushi, V.G. Surange (2014) “Impact of Poor Quality Cost in Automobile Industry” Int. Journal of Quality Engineering and Technology,Vol.4(1) pp. 21- 41
