Lab on the River – Snapshots of the St. Anthony Falls Laboratory

The St. Anthony Falls Laboratory was built on the site of a former Minneapolis pumping station (building in foreground at right) that was shut down in the early 1900s after a typhoid epidemic.

Lorenz Straub with a scale model of the proposed St. Anthony Falls Laboratory. 1937.

1936 pre-construction photo of the lab site. The pumping station has been deconstructed.

1936 construction of SAFL’s supply channel that would divert up to 300 cfs (cubic feet per second) of river water from above St. Anthony Falls through SAFL’s experimental facilities. Courtesy of University of Minnesota Archives.

Laboratory construction in 1936 included excavation of approximately 30,000 lbs of limestone to expand the bottom floor where SAFL’s outflow channel takes diverted water back to the river below St. Anthony Falls.

A 1936 view to the bottom of the laboratory where the turbine of the former pumping station still resided at time of construction. To this day, the basement floor of the lab is referred to as “the turbine level.”

SAFL’s exterior walls were constructed using limestone quarried on site, 1936-37.

Workers building the exterior walls of the laboratory in 1937.

1937 construction of the model floor, SAFL’s largest modeling/experimental space with access to the adjacent supply channel (middle of photo). Note the NSP (Northern States Power) diversion canal to the north (left of picture).

Construction photo of SAFL in 1937, showing extensive timber framing and the outflow channel, used to send water back to the river after its use in the laboratory. Viewed from near the river’s edge.

Construction of SAFL’s volumetric tanks used for deep water research, the basement level used for experiments, and lower deck. The basement level was designed to flood when the river levels rose above a certain level. Notice the Stone Arch Bridge and St. Anthony Falls in the background.

Continued construction of the laboratory in 1937. The building is starting to take shape. The volumetric tanks in the foreground are partially complete, later to be used for research requiring greater water depths.

The original outflow channel that moves water from the laboratory back to the Mississippi River was constructed for the former Minneapolis pumping station in the 1880s. The pumping station was demolished to make way for the lab. Note that the pumping station turbine (center of photo) still remains.

The basement level of the laboratory is constructed over the top of the outflow channel where water exits the building and rejoins the Mississippi River below the falls.

The completed St. Anthony Falls Laboratory in 1938. Notice the volumetric tanks in the foreground, and the city behind the lab.

View of the St. Anthony Falls and flood bypass channel alongside the newly completed St. Anthony Falls Laboratory with the volumetric basins visible in the foreground.

For several years, SAFL hosted a 1:50 scale model of the Mississippi River on its model floor. The model included the stretch of river from the Hennepin Avenue Bridge just upstream of St. Anthony Falls to the Washington Ave Bridge about one mile downstream. The model was built to better understand the potential effects upper and lower dams and locks on the Upper Mississippi would have on navigational conditions.

Water sent down an experimental channel (called a flume) enters SAFL’s outflow channel, sending the water back to the river. This particular experiment explored the aeration behavior of water in an open channel.

Lorenz Straub standing on the volumetric tank facility. Notice the Stone Arch Bridge in the background.

St. Anthony Falls Laboratory on the Minneapolis riverfront in 1942. The landmarks of Minneapolis are evident, as well as SAFL’s intimate relationship with the river.

A view across the upper deck at SAFL showing the river itself from the perspective of the laboratory in 1942. Modern visitors to the lab will notice that the building has been expanded considerably since then.

The Minneapolis Chamber of Commerce held a meeting on SAFL’s shop floor in the early 1940s. This is the first floor above the basement level, and not designed to be flooded when the river rises.

Lorenz Straub works at his desk at SAFL. He served as the director until his death in 1963.

Aerial view of the Minneapolis waterfront in 1942. Notice SAFL at the upper center of the riverfront, downstream of the horseshoe dam and upstream of the Stone Arch Bridge. You can also see the Pillsbury A Mill on the upper bank.

Aerial shot of the laboratory showing its relationship to the Stone Arch Bridge and with water coming down the flood bypass channel just to the left of the laboratory building.

SAFL under the Stone Arch Bridge from the river itself in the 1940s. This iconic picture is beloved and has been used extensively by SAFL in publications and materials since.