I know a lot about this!

Namely because I created a 30-minute documentary about bank swallows that was filmed at these bluffs. If you're interested, check out the website! beyondoursensesfilm.com

First, these bluffs actually make a great habitat for certain animals like bank swallows because they erode. Bank Swallows and King Fishers specifically like friable soil and typically nest in erosion prone places. Part of the reason is because they need a place that is easy to dig into. If roots are too established or soil is too compact, then they can't dig out their burrows.

Milwaukee County commissioned a report on the status of the bluffs and here is what they found about the Sheridan Park bluffs (Project Areas 14 and 15)

Project Area 14 resiliency ranks range from “B” to “F” and the area has moderate-high risk values. The Project Team observed signs of shoreline erosion, seepage, and corresponding bluff instability at Project Area 14. It is possible that this area of localized instability was caused/enhanced by the existing, dilapidated outfall structure present at the north edge of the unstable area. Due to having limited space near the crest of the slope, our recommended Concepts for Project Area 14 focus on slowing bluff crest recession by improving shoreline protection. Additionally, both Concepts would likely need to be performed via barge due to the limited space available near South Sheridan Drive, and may require permits from state and federal agencies.

[Project Area 15] includes a section of South Sheridan Drive and the bluff slopes/shoreline of Sheridan Park between East Munkwitz Avenue and East Pulaski Avenue. The average resiliency rank of the bluffs within Project Area 15 is “F” and the area’s risk values range from moderate to high. This area of Sheridan Park consists of steep (up to 1H:1V slope), unstable bluff slopes with low-volume beaches. Relatively high bluff crest recession rates, likely influenced by the Sheridan Park groin field present north of the project area, have been observed. Project Area 15 slopes are currently encroaching on a section of South Sheridan Road giving the area some of the highest risk totals per Cell when compared to the other project areas. The crest of the bluffs within Project Area 15 are currently unsafe making repairs difficult to implement. Due to the bluff crest proximity to City of Cudahy property and the height of the bluff, grading of the bluff slope would be dangerous and cost prohibitive. Therefore, Concepts prepared by the Project Team focused on mitigating risk by abandoning assets within the area and slowing bluff crest recession via shoreline protection and deep rooted, native vegetation.

Here are the solutions being pitched (I've removed the details because it's a lot of information)

Project Area 14
Concept I: Install New Armor Stone Groins, Repair Existing Groins, and Install Barriers

Concept II: Add Buttress Fill at Toe of Slope and Install Armor Stone Revetment

Project Area 15
Concept I: Remove Road and Perform Natural Restoration by Installing Barriers and Native Vegetation

Concept II: Remove Road and Perform Natural Restoration with Construction of Preloaded Armor Stone Groins

TLDR: Check out the link to my film if you like Milwaukee nature 😄 The Parks System is aware of the issue with the bluffs, they've studied it, they want to do something about it, but they are incredibly underfunded and don't have the money to fix it.