McKay Professor of Engineering and Applied Mathematics Myron B. Fiering '55, a world-renowned hydrologist, died Wednesday afternoon at Mt. Auburn Hospital after a sudden heart attack. He was 58.

Fiering, a tenured professor since 1969, studied water resources modeling and development.

He participated in many areas of the University outside of his scholarly work, from chairing the Faculty Athletic Committee to musical activities.

Dean of the Division of Applied Sciences Paul C. Martin '52 yesterday called Fiering "a very caring person with a good sense of humor and a light touch."

"Mike was a person who loved and was engaged in all aspects of this university in an amazing way," Martin said.

Fiering served as head tutor of both the Applied Math and Engineering Sciences departments. He was also involved in research with members of the Kennedy School of Government, Business School and Medical School teaching hospitals. He also served as a lifetime trustee of Beth Israel Hospital.

"He will be remembered as someone with a large number of interests, a diligent worker, and an excellent teacher," said McKay Professor of Environmental Engineering Joseph J. Harrington.

As a member of the Harvard Water Program, Fiering worked in the early 1960s on a study of waterlogging and salinity in the Indus River basin.

Consequently, he developed "a worldwide reputation in the area of water resources and water management" working for agencies such as the U.N. and the World Health Organization, Harrington said. Fiering was planning a January trip to Manila for the U.N.

Fiering was also involved in assisting physicians at Peter Bent Brigham and Mass General Hospitals to analyze optical methods of controlling fluid loss from burn patients.

More recently, Fiering had helped Rotch Professor of Atmospheric Science Michael B. MacElroy prepare a concentration in environmental sciences and public policy, currently under discussion by the Faculty Council.

McElroy said that Fiering's expertise on the flow of ground water and on statisticaltechniques were useful in critiquing proposalssubmitted to the council. Fiering was alsoplanning a new course he hoped would be integratedinto the new concentration.

McElroy called Fiering a "good friend" and"exceptional colleague."

"He was a colleague with a wonderful sense ofhumor and a generosity of spirit, who loved thisUniversity," McElroy said. "I was devastated."

Tawhid Ali '93, one of Fiering's researchassistants, described Fiering as a "mentor" whosesincere concern for undergraduates will be missed.

"He did care a lot about what undergraduateswere doing and what their future plans were," Alisaid.