Concepts familiar from grade-school algebra have broad ramifications in computer science.
Former Governor William Weld made a big splash when he jumped into the Charles River to prove its cleanliness, dazzling the public with his willingness to chance the taint of polluted water.
In Varanasi, India, 60,000 people take a daily "holy dip" in a 7-kilometer stretch of the Ganges River said to be a thousand times as polluted as the Charles at its worst -- and they do so without fanfare. For that multitude, the Ganges, often called Mother Ganga, represents divinity, and one droplet of its water is said to wash away the sins of many lifetimes.
In addition to being the eighth generation head of a temple, Dr. V.B. Mishra is an hydrologist and professor of civil engineering at Banaras Hindu University. He was at MIT on Wednesday, Nov. 18 to discuss a problem close to his home and his heart: pollution in the Ganges. His talk, "Cleaning the Ganges River: An Engineering Problem with Spiritual Dimensions," was sponsored by the Department of Urban Studies and Planning (DUSP).
"The river is goddess, the river is Mother. We cannot live without her in our lives," said Dr. Mishra, head priest or mahant of the Sankat Mochan Temple, which stands on the banks of the Ganges River in the city of Varanasi -- better known to Westerners by its colonial name of Banaras.
The Ganges is said to originate in a cave high in the Himalayas, and to have been blessed for centuries by the saints who have bathed in her waters. "The Ganges is a focal point in a city of many gods. It is where our philosophies converge," Dr. Mishra said.
"My scientific training says that something is not good about the river, and I know the consequences [of inaction]. At the same time, I take my holy dip in the river every morning. And I want, until the last day of my life, to be able to take that dip in the river," he said, explaining to the audience in Rm E25-111 that his dual perspectives on the Ganges's pollution problem -- religious and scientific -- have created a schism that "I carry in my personality with me."
The mahant put that schism to good use in 1982 when he founded the Sankat Mochan Foundation to launch a Clean the Ganges campaign to rid the river of its primarily biological contaminants, most of which come from raw sewage pumped directly into the river. A lesser amount of the pollution derives from bathers and the soaps they use. Still other contaminants come from animal carcasses and the remains of partially cremated human bodies sent floating down the Ganges.
The campaign soon gained wide popularity and the Indian government took up the banner. Since then, millions of dollars have been spent and some high-tech equipment installed: two treatment plants with sewage pumps and an electric crematorium were built near Varanasi. But today the Ganges is still extremely polluted.
"Without diagnosing the disease, the medicine was prescribed," said Professor Mishra. The heavy monsoon rains flood the sewage pumps, making them virtually inoperable five months a year. Similarly, electrical power in the country of nearly a billion people -- the world's largest democracy -- is unreliable, and for about five hours a day the pumps and crematorium are without it.
But there is hope. The foundation has proposed a different, low-tech solution that calls for large oxidation ponds to replace the two sewage treatment plants. The group's proposal has gained the approval of the people of Varanasi and is being championed by three international Friends of the Ganges groups in Australia, Sweden and the United States. However, an unwillingness on the part of the Indian government and some other vested interests is preventing the plan from moving forward, Professor Mishra said.
Following his talk and the screening of a video about the project, Paul Levy, an adjunct professor in DUSP and former head of the Massachusetts Water Resource Authority who directed the 10-year project to clean up the Charles River, explained why he believes the problem will be solved.
"First, there are millions of people living along the river who suffer from the effect of pollution. People are literally dying every day from cholera and other waterborne diseases," he said. "Second, the river is an important religious symbol, and its cleanliness holds tremendous spiritual meaning for hundreds of millions of people. Third, it's important for the image of the country of India to be seen as solving such an im-portant environmental issue." Professor Levy, who is currently dean of administration at Harvard Medical School, is a member of the advisory committee of the US Friends of the Ganges.
He became involved with the Ganges problem in 1992, when he was invited to Varanasi for a USAID-sponsored seminar on the topic. At last week's talk, Professor Mishra gave him a scarf to show gratitude for his efforts.
"The scarf is a lovely reminder of my personal connection to the people of Varanasi and the effort to clean the river," Professor Levy said afterward. "But more importantly, it symbolizes the connection that people throughout the world have to the overall values inherent in environmental protection."
On another note of connectivity, Fran Peavey, president and founder of the San Francisco-based Friends of the Ganges, reminded the audience that there is reason for everyone to care about the river. "When you turn on your tap, that water may have once been in the Ganges. There is no new water; it just gets recycled."
A version of this article appeared in MIT Tech Talk on December 9, 1998.