PN-23-14 NAB-2021-61285-M49 (HO DPW/South Meadow Ct./Pond & Stream Restoration)

Published March 23, 2023
Expiration date: 4/22/2023

                 Public Notice
U.S. Army Corps              In Reply to Application Number
of Engineers                    NAB-2021-61285-M49 (HO DPW/South Meadow Ct./Pond
                                            & Stream Restoration)

Baltimore District
PN-23-14                          Comment Period: March 23, 2023 to April 22, 2023                                      

This District has received an application for a Department of the Army permit pursuant to Section 404 of the Clean Water Act (33 USC 1344), as described below:


                              Mr. Charles Dammers, P.E.
                              Howard County DPW
                              9801 Broken Land Parkway
                              Columbia, Maryland 21046


The two stormwater management ponds are located on an unnamed tributary to the Little Patuxent River in Centennial Park, east of the terminus of South Meadow Court in Ellicott City, Howard County, Maryland. (39.246014, -76.858812).


The purpose of the project is to improve water quality treatment and public safety in the Little Patuxent watershed by decommissioning a failed stormwater management pond, retrofitting a sediment basin to comply with MD Code 378 safety standards, replacing a sewer line, and restoring two reaches of stream.


The project site consists of two in-line stormwater management facilities: one a stormwater management pond directly east of the cul-de-sac of South Meadow Court, and one sediment basin just north of Centennial Lake. The stormwater management pond outfalls to an ephemeral stream, which confluences with a perennial stream before entering a sediment basin that discharges to Centennial Lake. Both stormwater facilities are degraded in existing conditions and do not comply with MD Code 378 safety standards. Erosion has undermined the inflow and outfall points of the stormwater management pond and is encroaching upon an adjacent sewer line. The project proposes to decommission the stormwater management pond and construct a natural stream alignment through its footprint. Two new 30-inch reinforced concrete pipe storm drains will be constructed to convey flow from the decommissioned pond to the receiving tributary. The sewer line will be relocated to cross under the stream at a stable location with several feet of overhead cover. The project proposes to retrofit the downstream sediment basin to provide additional water quality treatment volume and improve embankment stability. The proposed work will excavate the basin to a lower elevation, expand the footprint of the basin, install a forebay, and reconstruct the facility embankment with a clay core, cutoff trench, and filter diaphragm. The basin will be constructed with a 20-foot by 10-foot riser structure and weir structure connected to a 72-inch reinforced concrete principal spillway pipe, which will discharge flow to a constructed plunge pool before entering Centennial Lake.

In addition to the stormwater work, the project proposes to restore the two streams entering the sediment basin to reduce erosion and create a stable tie-in to the new pond forebay. On the ephemeral tributary, the restoration proposes to raise the existing stream bed elevation and install cobble bed material, boulder sills, and log vanes. On the perennial tributary, the restoration proposes to grade streambanks to create a floodplain bench area and install an alternating sequence of riffles and pools in the stream. The project will grade depressional areas within the floodplain bench to create wetlands and will furnish the floodplain with woody debris.

The stormwater retrofits and stream restoration will permanently impact 490 linear feet (25,087 square feet) of perennial stream, 359 linear feet (1,223 square feet) of ephemeral stream, and 31 square feet of forested nontidal wetlands. Construction access and dewatering will temporarily impact 11 linear feet (1,368 square feet) of perennial stream and 22 square feet of forested nontidal wetlands.



Stream Impact (lf)

Stream Impact (sq. ft.)

Forested Wetland Impact (sq. ft.)


(Section 10/404/408)

Permanent impacts associated with stormwater retrofits and stream restoration

490 (perennial)

359 (ephemeral)

25, 087 (perennial)

1,223 (ephemeral)



Section 404

Temporary impacts associated with construction access and dewatering

11 (perennial)

1,368 (perennial)


Section 404


The United States Army Corps of Engineers, as the lead federal agency, is responsible for all coordination pursuant to applicable federal authorities.


Avoidance and minimization:

As part of the planning process for the South Meadow Court Pond Retrofit and Stream Restoration project, steps were taken to ensure avoidance and minimization of impacts to aquatic resources to the maximum extent practicable based on the existing site conditions. The two stormwater facilities were constructed in the 1980s and do not provide sufficient water quality treatment for current runoff volumes. Additionally, neither facility is currently in compliance with MD Code 378 safety standards. The outfall tributary for the stormwater management pond has eroded and features an approximately 8-foot deep headcut at the end section of the pond riser. Continued erosion could damage the outfall structure and lead to a potential pond breach. The embankment of the sediment basin has deteriorated and has required maintenance in recent years. Additionally, frequent overtopping of the basin has caused erosion between the outfall channel and Centennial Lake. The project is designed to improve the long-term stability of the basin and to reduce sediment discharges to Centennial Lake and the Little Patuxent River.

The project will construct a natural stream system within the footprint of the decommissioned pond. Stream restoration work is limited to two reaches of stream that are degraded in existing conditions. Geomorphic assessments performed on the two inflow tributaries classified bank erosion hazard index and near bank stress scores as ‘Very High’ and estimated that in-stream erosion is contributing 18 and 45 tons of sediment per year, respectively. Further lateral erosion could damage an adjacent sewer line and pollute Centennial Lake. The stream restoration will result in overall functional uplift by increasing stream–floodplain access, reducing erosion, improving instream habitat, and creating new riparian wetland areas. The restoration has been designed to avoid impacts to specimen trees, and all disturbed riparian areas will be replanted with native trees and shrubs.


This project will be evaluated pursuant to Corps Regulatory Program Regulations (33 CFR Parts 320-332). The decision whether to issue a permit will be based on an evaluation of the probable impacts, including cumulative impacts of the proposed activity on the public interest. That decision will reflect the national concern for both protection and utilization of important resources. The benefit, which reasonable may be expected to accrue from the proposal, must be balanced against its reasonably foreseeable detriments. All factors, which may be relevant to the proposal will be considered, including the cumulative effects thereof; among those are conservation, economic, aesthetics, general environmental concerns, wetlands, cultural values, fish and wildlife values, flood hazards, flood plain values, land use, navigation, shoreline erosion and accretion, recreation, water supply and conservation, water quality, energy needs, safety, food and fiber production, mineral needs, and consideration of property ownership and in general, the needs and welfare of the people. The evaluation of the impact of this project will also include application of the Clean Water Act Section 404(b)(1) Guidelines promulgated by the Administrator, United States Environmental Protection Agency.


A preliminary review of this application indicates that the proposed work is not likely to adversely affect federally listed rare, threatened, or endangered species or their critical habitat, pursuant to Section 7 of the Endangered Species Act, as amended. As the evaluation of this application continues, additional information may become available which could modify this preliminary determination.


The Magnuson-Stevens Fishery Conservation and Management Act, as amended by the Sustainable Fisheries Act of 1996 (Public Law 04-267), requires all federal agencies to consult with the National Marine Fisheries Service on all actions, or proposed actions, permitted, funded, or undertaken by the agency that may adversely affect Essential Fish Habitat (EFH), including species of concern, life cycle habitat, or Habitat Areas of Particular Concern. The Baltimore District has made a preliminary determination that the project is not within EFH. The Baltimore District has made a preliminary determination that mitigative measures are not required to minimize adverse effects on EFH at this time. This determination may be modified if additional information indicates otherwise.


Pursuant to Section 106 of the National Historic Preservation Act of 1966 and applicable guidance, the Corps has reviewed the latest published version of the National Register of Historic Places and initially determined that no registered properties listed as eligible for inclusion, therein, are located at the site of the proposed work. The Corps has made the preliminary determination that the proposed project would have no adverse effect on historic properties. The Corps final eligibility and effect determination will be based on coordination with the State Historic Preservation Office as appropriate and required, and with full consideration given to the proposed undertaking’s potential direct and indirect effects on historic properties within the Corps’ identified permit area.


Section 106 of the National Historic Preservation Act also requires federal agencies to consult with federally recognized American Indian tribes that attach religious and cultural significance to historic properties that may be affected by the agency’s undertaking. Corps Tribal Consultation Policy mandates an open, timely, meaningful, collaborative, and effective deliberative communication process that emphasizes trust, respect, and shared responsibility. The policy further emphasizes that, to the extent practicable and permitted by law, consultation works toward mutual consensus and begins at the earliest planning stages before decisions are made and actions taken. The Corps final eligibility and effect determination will be based on coordination with interested tribes, in accordance with the Corps current tribal standard operating procedures as appropriate and required, and with full consideration given to the proposed undertaking’s potential direct and indirect effects on tribal resources.


All Section 408 proposals will be coordinated internally at the United States Army Corps of Engineers. The Section 408 decision will be issued along with the Section 404 and/or Section 10 decision. Please see the following link for more information regarding Section 408:


The applicant is required to obtain a water quality certification in accordance with Section 401 of the Clean Water Act.


The Corps of Engineers is soliciting comments from the public; federal, state, and local agencies and officials; Indian Tribes; and other interested parties in order to consider and evaluate the impacts of this proposed activity. Any comments received will be considered by the Corps of Engineers to determine whether to issue, modify, condition, or deny a permit for this proposal. To make this decision, comments are used to assess impacts on endangered species, historic properties, water quality, general environmental effects, and the other public interest factors listed above. Comments are used in the preparation of an Environmental Assessment and/or an Environmental Impact Statement pursuant to the National Environmental Policy Act. Comments provided will become part of the public record for this action and are subject to release to the public through the Freedom of Information Act. Comments are also used to determine the need for a public hearing and to determine the overall public interest of the proposed activity.

Written comments concerning the work described above related to the factors listed above or other pertinent factors must be received by the United States Army Corps of Engineers, Baltimore District within the comment period specified above through postal mail at the address below or electronic submission to the project manager email address below. Written comments should reference the Application Number


Any person who has an interest which may be adversely affected by the issuance of this permit may request a public hearing. The request, which must be in writing, must be received within the comment period as specified above to receive consideration. Also, it must clearly set forth the interest which may be adversely affected by this activity and the manner in which the interest may be adversely affected. The public hearing request may be submitted by electronic mail or mailed to the following address:

Matt Hynson
U.S. Army Corps of Engineers, Baltimore District
Regulatory Branch
2 Hopkins Plaza
Baltimore, Maryland 21201

It is requested that you communicate this information concerning the proposed work to any persons known by you to be interested, who did not receive a copy of this notice.

General information regarding the Corps’ permitting process can be found on our website at This public notice has been prepared in accordance with Corps implementing regulations at 33 CFR 325.3. If you have any questions concerning this specific project or would like to request a paper copy of this public notice, please contact Matt Hynson at or (410) 689-9532. This public notice is issued by the Chief, Regulatory Branch.