Bloede Dam

Bloede Dam 

​Current Progress

The Bloede Dam Removal project has been delayed about 14 days due to the May flood event. The storm damage is currently being assessed. The dam breach is now scheduled for the first week in September. Due to the continuing work on the project and to ensure public safety, the Howard County side of of the Patapsco River from Ilchester Road to just past the current dam site will be closed starting August 1st. Please plan your outings to the Park accordingly.

Bloede Dam 

Looking Forward:
Construction crews will be working on the upstream thrust blocks and completing the work on the Sewer By-Pass System. Engineers will continue preparations for the dam demolition.

**Due to inclement weather or other unforeseen circumstances construction times and dates  could change during the course of the project.  All updates and changes can be found on our website.

Why Remove Bloede Dam?

  • Improve public safety (human deaths & injuries have taken place at the dam)
  • Complement upstream restoration work (Union & Simkins dam removal)
  • Improve fish passage (ladder has been unsuccessful & expensive to maintain)
  • Improve stream connectivity for fish and aquatic organisms

​Current Progress - Bloede Dam Removal Project

Daily photo uploaded from on-site Spartan GoCam. 

The Department of Natural Resources and its partners plan to begin the removal of the Bloede Dam in summer/fall 2017. The first phase of the project will involve the relocation of the 42" main sewer line which runs through the dam. This will result in the closure of a portion of the Grist Mill Trail for approximately 18-20 months. This initial phase will also require the removal of approximately 7 acres of trees in the vicinity of the dam and Grist Mill Trail. A Forest Conservation Plan has been developed to ensure successful reforestation (more details to come). Once the relocation of the sewer line is complete, work to remove the actual dam structure will begin in the fall of 2018. During all phases of the project, visitors should expect to see and hear increased truck activity between Illchester Bridge and Bloede Dam.

Materials presented at the Open House can be downloaded by clicking the link below:
Bloede Dam Removal Open House on January 29 (13MB sized file)
Bloede Dam Public Comments Response 2015

To date, the Department of Natural Resources and it's partners have completed the following tasks.:

  • Received permits
  • Selected the contractor
  • Put project out for bid
  • Completed 99% design plans
  • The department held an open house on January 29th 2015 to present the 60% design plans and inform the public of important topics which could impact them.
  • Posted responses to comments received at the open house.
  • Estimated sediment volumes using MD Geological Service seismic survey data and soil borings.
  • Analyzed sediment cores for physical properties and pollutants.
  • Met with permitting agencies to discuss the Bloede Dam removal options.
  • Met with Baltimore and Howard County Department of Public Works to discuss options for minimizing impacts to the sewer line.

Looking ahead, the department and it's partners will work on the following tasks:

  • Mobilize Equipment
  • Close portion of Grist Mill Trail
  • Install Office Trailer
  • Install Erosion and Sediment Control measures
  • Install River Crossing
  • Clear wooded area behind the dam between Grist Mill Trail and the River
  • ​Begin installing new sewer line​

​​Tentative timeline:
  • 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 a cultural and historic resource, a portion of the dam structure will be retained on the Howard County side with the placement of appropriate interpretive displays on location and possibly another interpretative display on the Baltimore County side.

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

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