Buchart-Horn Designs A Unique Aeration System To Support Fish At Inner Harbor

Buchart-Horn Designs A Unique Aeration
System To Support Fish At Inner Harbor

The new aeration
system at Inner Harbor.

Since it opened in the early 1970's, Baltimore's Inner Harbor has been pulling in visitors and inner-city planners like a magnet. The list of crowd-pleasing attractions was long at the start and has since gotten longer.

The scheme here cultivates the positive and eliminates the negative.

Ships, piers and all things nautical are displayed to delight us all, while the noisy, greasy machinery that once made things move has been removed or painted and frozen for display.

There have also been major improvements to water quality in this popular tourist harbor.

One project, funded by a state grant to the City of Baltimore, sought to enhance aquatic life within the Harbor where the Jones Falls channel joins the Patapsco River.

Through an on-call contract with the State of Maryland, using state grant funds awarded to the City of Baltimore's Department of Public Works, Buchart-Horn's engineers designed an aeration system that would serve to add oxygen and also destratify and agitate the water column in the Jones Falls channel between the Public Works Museum on Pier 7 and the Pier 6 Concert Pavilion and Columbus Research Center.

"From time to time, the tidal water would come in and form an anoxic layer on the bottom harmful to fish," said Buchart-Horn's Project Manager.

"The solution was to destratify the water in the problem area and add supplemental oxygen."

Buchart-Horn's design for remediation called for adding compressors in the Eastern Avenue Pumping Station to force air through underwater pipes to diffusers that mix air and water and raise the oxygen content in the water.

While diffusers have been used frequently on lakes and ponds, the Inner Harbor aerators utilized a unique design for a tidal application.

The aeration system is composed of PVC pipe, ductile iron pipe and ABS diffusers. It is anchored on the channel bottom on concrete platforms. The foundation platforms were precast on shore and lowered into position with a crane.

The bubbles from the aeration system that visitors might see as one more fountain-like attraction provide substantial environmental benefits. Oxygen levels in the channel have improved.

"It's exciting to see schools of herring in the area and it tells you the system helps," said Buchart-Horn's Project Manager.

According to Baltimore Public Works Director George G. Balog, "We know oxygen levels have improved as a result of the aerators. Employees at the Pumping Station tell us that the water is clearer and that the fish populations are increasing. We know it's working and we're happy with the results."