Jonathan E. "Jon" Pettit, a Seattle-based managing principal of architect-engineer DLR Group, Omaha, and a 36-year industry veteran, died on Aug. 19 of cancer, the company announced on Sept. 3. He was 61. PETTITPettit led Seattle operations and provided strategic direction for DLR's growth into a regional design leader in the corporate, justice and education sectors, says the firm.He also was key in building its retail and workplace practice nationally and, in the 1980s, led the firm's acquisition of architect John Graham & Associates.DLR ranks at No. 101 on ENR's list of Top 500 Design Firms, with $116.3 million in
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.