Bloede Dam

Bloede Dam 


 ​​After years of planning by the Patapsco River Restoration Partnership, Bloede Dam the first blockage on the Patapsco River was breached on September 11th! For the first time in over a hundred years, the Patapsco River is no longer flowing over the dam but around it. 

A full view of the historic 1906 slab and buttress dam was revealed as the water stopped flowing over it. A team from the Historic Buildings Survey and Historic American Engineering Record of the National Park Service arrived at the dam site to scan, measure, and photograph it. This information will provide comprehensive historical documentation of the Bloede Dam for the Library of Congress. In addition, the team will create a 3-D model for a new park visitor center.  

The breach created by an explosive blast is the first step in removing the physical structure. As the water, sand and gravel move out of the impounded area above the dam, the construction crew will begin to mechanically remove the concrete piece-by-piece over the next few weeks. Photos of the removal process will be posted on this web site as work progresses. The dam construction area in Patapsco State Park will remain closed to the public during this work.

We aren’t done yet! The restoration project still has plenty of work to do before the project is completed in 2019. The breach is one big step for the Patapsco River and one giant leap for aquatic resources and public safety.

View a story map of the Bloede Dam Project

This story map​ created by our partner, American Rivers, guides you through the history of the Bloede Dam, its relationship with the Patapsco River and its ultimate removal.


Daily photo uploaded from on-site Spartan GoCam. 

​View all of the pictures from the Bloede Dam Removal​.


  • Review bids - May 2016
  • Select contractor - September 2016
  • Mobilize Equipment - August 2017
  • Close Grist Mill Trail -  September 2017
  • Install river crossing -  September 2017
  • Clear wooded area - September/October 2017
  • Begin sewer line relocation - October 2017
  • Begin installing new sewer line - winter 2017 - spring 2018
  • Remove old sewer line - summer 2018
  • Remove Bloede dam - late summer/fall 2018
  • Construct overlook and rebuild Grist Mill Trail - fall/winter 2018
  • Plant new trees/vegetation - early 2019
  • Demobilize - spring 2019

Bloede Dam Project

Problem: The Bloede Dam is located within the Patapsco River State Park and was built in 1907. The dam is a public safety concern (deaths have occurred), an obstacle for fish passage, and it fragments river continuity and aquatic habitats.

Responsibility: Bloede dam is owned by the Maryland Department of Natural Resources.

Process: A feasibility study was commissioned to evaluate the dam's negative impact on the ecology of the Patapsco River and issues of public safety. After a thorough analysis and public input (2011-2012), the Department and project partners made the decision to move forward with the Bloede Dam removal with passive sediment management.

Goals of the Bloede project:

  1. Restore Fish and Aquatic Organism Passage
    The Patapsco River once supported large runs of shad, herring, and American eels, but the construction of dams has blocked these historic migrations. The fish ladders constructed in the 1990's have proven to be ineffective at passing fish – especially American eel.
  2. Improvement of Public Safety
    The Bloede dam is a significant public safety hazard, several deaths have occurred at or near the dam.
  3. Consider Historic, Cultural and Recreational Values
    The Bloede Dam was built in the early 1900’s and is part of the Patapsco’s rich history. It is also a major feature of the Patapsco Valley State Park. Similarly, herring, and shad were once abundant and a staple of settlers in the Patapsco Valley. The cultural significance of each of these will be commemorated as part of this project and recreational boating and fishing values promoted.

Our Vision

With the removal of all or most of Bloede Dam, the department envisions a restored Patapsco River System with a wide range of benefits and long-term cost savings. It is recognized that this decision is not without potential adverse impacts.

A significant historical structure in Patapsco Valley State Park will be lost, there will be short-term impacts to the ecology of the river, fishing and other recreational opportunities will be affected, and there will be temporary inconvenience to park visitors.

However, there will be long-term ecological benefits to the Patapsco River and the Chesapeake Bay, including:

  • Passage of anadromous fish and eels, thus achieving fish passage objectives
  • Improved recreational opportunities (fishing, canoeing, kayaking, tubing) and enhanced public safety (removal of drowning hazard and elimination of dam-related injuries)
  • Healthier populations of native fish species
  • Increased diversity of aquatic insects
  • Cooler, oxygen-rich waters that improve the fishery
  • Long-term cost savings related to ongoing maintenance and repair of the dam structure and an ineffective fish ladder
  • A more scenic and natural setting; the present dam aesthetics that some find attractive will be replaced over time with a rocky, more natural cascading river environment and setting

To address the loss of the cultural and historic aspects of the Bloede Dam, the project partners will be developing interpretive displays to be posted on location.   

The department invites you to continue to submit written comments on this project, please email:

Partners with: NOAA Logo American Rivers Logo