Rural Water - Quarter 4, 2008 - (Page 36)

The impact of being rid of the chocolate water in town has been significant. In fact, on one occasion when the town failed to have adequate aluminum sulfate on hand and the water returned to the chocolate variety for a day, there was quite a commotion in town. designers were faced with the unique problem of ﬁtting the plant components into a predetermined size and conﬁguration rather than simply designing a new structure to fulﬁ ll the design conﬁguration. The municipality of Marcala provided up to six laborers per day and transported all the materials to the site. During the worst of the rainy season, this required actually carrying the materials the last several hundred yards up the mountainside. Also, the municipality provided all the sand and gravel and the wood needed for concrete forms. IRWA provided the funds to purchase the remaining materials and for the project supervision and skilled labor. During the construction period Fred spent one to two weeks per month in Marcala to translate the students’ design into construction plans and to assist with location of locally available materials. Almost all of the materials were purchased in the local market except for a few ferrco adapters and hand-tight plugs, which were carried to Honduras. In January, the Cornell students visited the project to ﬁ nalize design details and to assist with construction. During this visit they also inaugurated construction of a new plant at Tamara Honduras that they had also designed dur36 • Fourth Quarter 2008 ing the previous semester. They visited the LA 34 and Ojojona treatment plants, which had been constructed as part of the Cornell-IRWA partnership. On this visit, the students determined that the sedimentation portion of the plant was near the low end of the recommended range and a decision was made shortly thereafter to add an additional sedimentation tank to increase the sedimentation time by 25 percent. This decision resulted in a month’s delay in construction completion and slight increase in cost. The total project cost was approximately $60,000, partially due to the additional sed tank but also the municipality decision to provide a high quality rooﬁ ng system for the entire plant. However, even with these cost increases, the cost of the plant was only around 12 percent of the projected cost of the mechanical plant that had been proposed by the consulting engineers. Construction of the plant neared completion in May, and Lupe and Fred traveled to Honduras to start it up. On May 20, the plant was started up with the raw water turbidity running in the mid 30’s ntu and the operators went through their ﬁ rst practical on the job training. Unfortunately for the operator working that ﬁ rst shift, a storm hit the area late that night and the turbidity jumped to over 700 ntu. By increasing the alum feed, the operator maintained control until early in the morning, and when Lupe and Fred arrived at the plant at around 6:00 a.m., the turbidity had moved through the sedimentation tanks but still not out to the system. Less than 24 hours into operations, the plant faced its ﬁ rst test of how to recover from an upset, and it was a pleasure to ﬁ nd that within one hour, it was properly operating again. To the surprise of the community, they had clean water even when Chiﬂador was roaring through the town dark brown. Over the ﬁ rst ﬁ ve months of operations, the Marcala treatment plant has continued to function well and has been removing 98-99 percent of the turbidity almost all the time. There have been numerous storm events with the turbidity hitting the 500 to 750 range, and on one occasion the operator recorded a spike of 1050. The operators are learning when to reduce the ﬂow or when to shut the plant down and by experience are learning to adjust the alum feed to compensate for the ﬂashy water. Their job is not easy, as they work 24-hour shifts every other day and without electricity at the plant must work with the light of a ﬂashlight. They have a manually operated single jar tester, which lets them get a quick look at the alum feed effectiveness and a portable turbidity meter. They also control the chlorine feed for the system by adjusting a drip feed tank. They are learning the proper scheme to ﬂush the sludge that drops out in the ﬂocculator and have established a routine to ﬂush the excess sludge blanket from the sedimentation tanks. The impact of being rid of the chocolate water in town has been signiﬁcant. In fact, on one occasion when the town failed to have adequate aluminum sulfate on hand and the water returned to the chocolate variety for a day, there was quite a commotion in town. A citizen’s panel has been meeting to discuss the formation of an independent water board to operate the system. Also Marcala has to face up to a major water loss problem that is resulting in much higher than expected chemical cost. After 50 years of “chocolate” water, Marcala now not only has clean water but recent bacteriological studies found the water free from contamination. For IRWA, the Marcala treatment plant has provided the solid evidence that the “let’s get it done common sense approach of rural water” that has worked in the U.S. is transferable to the developing world. The provision of technical assistance through our circuit rider program is having an impact across Central America, and the Marcala treatment plant is a reality because IRWA has been willing to take on tough problems as well as easy ones. While wealthy nations and international banks throw millions of dollars at problems of this type, IRWA has shown that small amounts of money when combined with knowledge and local skills and common sense are far more effective in providing sustainable practical solutions to even the toughest of problems.

Table of Contents Feed for the Digital Edition of Rural Water - Quarter 4, 2008

Rural Water - Quarter 4, 2008 Contents From the President Rural Water: Where are We Headed? The Future of Water in America Bank Collateral Controls in Nervous Times Bottle of Water or Billion Dollar Bully? Aqua Chocolate No Mas Why Even Small Water Systems Should Have Personnel Policy Manuals Safe Drinking Water Regulatory Update 2008 NRWA Industry Event Throwing My Loop Advertisers.com Index to Advertisers From the CEO

Rural Water - Quarter 4, 2008

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