On January 23, 1925, Philadelphia Electric Company awarded the construction contract for the dam to Stone & Webster of Boston,[1] who did the design.

[3] Some 5,000 workers flocked to this rural northeastern corner of Maryland, seeking to earn good pay as construction got underway.

[4] In addition to those working directly on the dam, large numbers relocated railroad tracks, paved new roads, and constructed steel towers to stretch the heavy transmission lines toward Philadelphia.

[citation needed] When Maryland Public Television aired its documentary, "Conowingo Dam: Power on the Susquehanna" for Chesapeake Bay Week in April 2016, the question came up about how many workers died performing their duties.

[5] While investigating the death of Hunter H. Bettis on November 26, 1927, Darlington Coroner Wiliam B. Selse commented in The Baltimore Sun that more than twenty men had lost their lives.

In an attempt to create a registry or census of job-related fatalities, death certificates, newspaper accounts, and funeral home books were examined.

During Hurricane Agnes, in June 1972, all 53 floodgates were opened, for only the second time, and explosives planted to blow a section of the weir, as the waters rose during the early morning hours of June 24 within 5 feet (1.52 m) of topping the dam (a record crest of 111.5 ft (34.0 m), 3 feet (0.91 m) above normal level for the entire 14-mile (23 km) long Conowingo Reservoir.)

The Susquehanna River saw water levels of over 26.25 feet (8.00 m), placing nearby cities, like Port Deposit, at risk of flooding like in 2011.

[15] The Coast Guard issued warnings for all vessels in the Chesapeake Bay regarding the fields of debris, floating and submerged, that had been released when the floodgates opened.

In low rainfall or drought conditions, balancing the desire to maintain the reservoir level with the water flow needs for the downstream ecology is one of the challenges faced by the dam operators.

Normally, the reservoirs above each dam trap sediment and nutrients that run off from the Susquehanna River watershed and prevent some of that from reaching the Chesapeake Bay.

A 1998 USGS study suggests that the reservoirs may reach capacity before 2020, and cease to reduce the nutrient and sediment load hitting the bay.

While the surrounding area is home to dozens of the eagles year-round, upwards of 200 more will migrate from places like New York and Canada, where lakes and rivers freeze over in the winter and limit fishing opportunities.

[19] Their numbers typically peak from November to January, with the eagles taking advantage of the dam's turbines stunning fish swimming downriver to make for easy hunting.