Wilson Avenue - one of Chicago's Water Intake Crib Lights

The City of Chicago's originally pulled its water from the Chicago River, but with rapid growth around the river combined with the river serving as a convenient dumping place for the city’s waste, it was not long before the river became a virtual open sewer.

 

The Chicago River near the turn of the nineteenth century

In order to obtain fresh water, the city of Chicago began pumping water from the harbor. However, the waters near shore soon became too polluted to use, and in 1865 the City established a large timber crib out in Lake Michigan where water was collected and pulled through a hand-dug tunnel beneath the lake to a pumping station on shore. The structure was known as the Two Mile Intake Crib by virtue of its location two miles offshore. As can be seen in this contemporary lithograph, by virtue of its location in the lake, the structure was outfitted with a lantern and served as an aid to navigation both warning of its presence and guiding mariners into the harbor.

Lithograph of Chicago's Two Mile Crib

 As the great city of Chicago grew over the ensuing years, a number of additional water intake cribs and their connecting tunnels to shore were built off the harbor. One of these structures was known as the Wilson Avenue intake crib as a result of its tulle system connecting to a new pumping station at the foot of Wilson Avenue. Work on crib began in 1915 with the sinking of a steel caisson having a diameter of ninety feet. Built using square-hewn granite blocks, the superstructure served to protect a forty-foot diameter inner well chamber and as housing for the city employees who staffed the plant and tended the light that would be erected at the center of its roof. The photograph below shows work progressing on erecting the granite walls of the structure.

Construction underway on the Wilson Avenue water intake crib

All told, the Wilson Avenue Intake Crib supplied eight miles of water tunnels, which were hand-dug through the bedrock beneath Lake Michigan - a tremendous feat of engineering and back-breaking labor. This 1916 photograph shows the interior of one of these tunnels after completion.

Inside one of the Wilson Avenue Water Intake Crib tunnels

When they were approximately half way through the construction of the Wilson Avenue intake crib in Chicago, the Engineers found that the caisson had settled, causing the superstructure to be sitting a few degrees from horizontal. Holes were bored beneath the low side of the caisson and hydraulic cement was pumped into them, lifting the structure back to the correct orientation. This photograph taken in 1916 shows one of the engineers on a platform which was erected in the center of the superstructure, using a theodolite to ensure the top surface of the granite walls had been brought back to horizontal.

Engineer checking the structure for level

This photograph from a 1926 edition of Popular Science magazine was taken from a Water Department supply tug approaching the Wilson Avenue intake crib in winter.

The Wilson Avenue Intake Crib in wither

 Winter was a particularly difficult time for the crews stationed on Chicago's intake cribs, as they had to toil with picks and poles to prevent ice from building to the point that it clogged the main intake at the center of the well room within the structure, as seen in this 1926 photograph. When the temperature plummeted to sub zero levels, and ice formed thick and fast, small dynamite charges were used to break the ice to keep the water flowing. A dangerous, but necessary remedy in such a confined location.

Removing ice from the water intake

Crews at Chicago's intake cribs not only had to contend with their water department duties, but they also had to maintain the aid to navigation atop the center of the crib. Here we see one of the crew members cleaning the lantern glass atop the Wilson Avenue intake crib.

cleaning the lantern glass atop the Wilson Avenue intake crib.

 
In a manner similar to that adopted at offshore lighthouses, Chicago's water intake cribs were staffed by four to five man crews with one man on a week's shore leave every fourth or fifth week. Supplies and crews were transported to and from the cribs by Water Department tugs, as seen in this 1950 photograph from one of the tugs approaching the Wilson Avenue Crib.

A crew swap by Water Department tender at the Wilson Avenue Water Intake Crib

While working Chicago's water intake cribs could at times be a back-breaking job, the living conditions were good with fairly expansive quarters and all conveniences of the day. This photograph taken at the 68th Street Intake Crib shows the crew gathering for Thanksgiving dinner. From the manner of their dress, we can discern that their quarters were well heated, and their girth hints that they certainly were not short of food! Crews continued to man the intake cribs until the 1990's, when the decision was made to maintain them from shore.

Thanksgiving dinner at one of Chicago's Water Intake Cribs

This photograph of the Wilson Avenue water intake crib was taken in 2010 during our Southern Lake Michigan Excursion, and shows the wonderful vista city that would have tantalized the crib tenders when they were still assigned there. Since "9/11" the cribs intake are considered to be a target for terrorism, and there are sophisticated surveillance systems installed all around them along with numerous "Keep Off" signs posted. The good folks of Chicago see this cribs out in the lake, but precious little is known of them. In 2007, the Chicago Tribune approached the Water Department seeking permission to visit the cribs as part of their "Unauthorized" series in which they visit places around in the Metro area which are normally closed to public access. However, the cribs are considered so sensitive that their request was flatly denied. 

The keepers on Chicago's Intake Cribs had a tantalizing view of the city skyline

As can be seen in the photograph below from 2010. the glass has been removed from the lantern atop Chicago's Wilson Avenue water intake crib, and as is the case with most historic maritime structures, the structure now serves as a roost for a huge flock of cormorants and gulls. The structure still serves as an active aid to navigation and in 2010 was lighted by a Tideland Signal 300mm optic powered by city electricity supplied by a submarine cable.

The lantern atop Chicago's Wilson Avenue Intake Crib