Lower Monocacy Watershed Implementation Plan

October 2014

Prepared for:

Montgomery County Department of Environmental Protection 255 Rockville Pike, Suite 120 Rockville, MD 20850

Prepared by:

Lower Monocacy Watershed Implementation Plan

Lower Monocacy Watershed Implementation Plan

Table of Contents

Acronyms List ...... 2 1 Goals and Existing Conditions ...... 3 1.1 Introduction to the Implementation Plan and Watershed Goals ...... 3 1.2 Existing Conditions in the Lower Monocacy Watershed ...... 5 1.3 Problems Facing the Lower Monocacy Watershed ...... 10 1.4 Existing Pollutant Loads and Impervious Surfaces ...... 13 2 Inventory of Provisional Restoration Candidates ...... 16 2.1 Types of Restoration Practices ...... 16 2.2 Inventory of Previously Identified Projects ...... 17 3 Evaluation of the Restoration Strategies to Meet MS4 Permit and TMDL Requirement ..... 19 3.1 Pollutant Load Tracking ...... 19 3.2 Desktop Review of BMP Coverage ...... 19 3.3 Summary of Watershed Treatment Model Scenarios ...... 20 3.4 Preliminary Results of the Sediment, Bacteria and Phosphorus Load Reduction Analysis ...... 30 3.5 Trash Reduction and Nitrogen Load Tracking ...... 36 3.6 Impervious Cover Tracking ...... 37 4 Action Inventory Implementation Schedule ...... 39 4.1 Lower Monocacy Watershed Implementation Schedule ...... 39 5 References ...... 41 Appendix A List of High Priority Projects

Notes to Reader: 1. Throughout this Plan there are text boxes such as this that focus on public outreach and stewardship elements to consider for the Plan. In addition, there are references to Practice Sheets which have been developed that are general strategies that apply countywide but will require some customization on a watershed basis to reflect certain stakeholder demographics and priorities. These practice sheets are included as an appendix to the Countywide Coordinated Implementation Strategy. 2. Environmental Site Design (ESD) is defined within the 2010 Maryland Stormwater Design Manual as the use of small-scale stormwater management practices, nonstructural techniques, and better site planning to mimic natural hydrologic cycling of rainwater and minimize the impact of land development on water resources. The application of the term is focused on new and redevelopment projects, and does not explicitly address or consider retrofit applications where site constraints such as drainage area, utilities, and urban soil quality are significant factors. This watershed implementation plan uses the term ESD in a more flexible manner to include structural practices such as bioretention, vegetated filters, and infiltration that provide distributed runoff management using filtering, infiltration, and vegetative uptake processes to treat the water quality volume to the maximum extent practicable. These practices are also thought of as Low Impact Development (LID) practices.

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Acronyms List MNCPPC – Maryland National Capital Parks and Planning Commission

BMPs – best management practices MPN – most probable number

CBP – Chesapeake Bay Program MPR – maximum practicable reductions

DA – drainage area MS4 – municipal separate storm sewer

system DEP – Department of Environmental

Protection NPDES – National Pollutant Discharge

Elimination System DF – discount factor

RR – runoff reduction DU – dwelling unit

SCD – Soil Conservation District EPA – Environmental Protection Agency

SPA – Special Protection Area ESD – environmental site design

TFPI – Trash Free Potomac Watershed GIS – geographic information systems Initiative

HOA – homeowners association TMDLs – total maximum daily loads

IA – impervious area TN – total nitrogen

IC – impervious cover TP – total phosphorus

LDR – low density residential TSS – total suspended solids

LID – low impact development USACE – Army Corps of Engineers

MDE – Maryland Department of the WLAs – waste load allocations Environment

WQPC – water quality protection charge MEP – maximum extent practicable

WRAP- Watershed Restoration Action Plan MDP – Maryland Department of Planning

WTM – watershed treatment model

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1 Goals and Existing Conditions

1.1 Introduction to the Implementation Plan and Watershed Goals

This Implementation Plan for Lower Monocacy Outreach and Stewardship Strategy provides updated information from the document The primary messages for delivery in submitted to MDE in February 2011. The Plan was this watershed will pertain to activities developed in order to quantitatively demonstrate the County is undertaking to reduce compliance with the County’s National Pollutant runoff, control sediment and erosion, Discharge Elimination System (NPDES) Municipal reduce bacterial loads, reduce phosphorus loads, and manage trash Separate Storm Sewer System (MS4) Permit. The and litter. Plan must meet the MS4 Permit’s three major requirements:

• Assigned wasteload allocations (WLAs) for EPA-approved Total Maximum Daily Loads (TMDLs) • Watershed restoration via runoff management and impervious cover treatment • Trash and litter management to meet the commitments of the Potomac River Watershed Trash Treaty

The Plan outlines a comprehensive roadmap for watershed restoration that targets runoff, pollutants, and trash and litter management- including information pertinent to effectively include stakeholders in watershed restoration. The County MS4 permit area in the Lower Monocacy covers less than 10% of the total watershed area. The Plan focuses on the restoration effort within this MS4 Permit area. Areas not covered under the County's MS4 Permit include areas with rural zoning and federal and state properties, state roads, and municipalities that have separate MS4 permits. The County MS4 Permit area has approximately 10% impervious cover within the Lower Monocacy watershed.

This revised version reflects TMDLs approved since 2011 and results of more detailed desktop and field evaluations during 2013 to identify potential restoration practices. EPA approved the Lower Monocacy Sediment TMDL in March 2009, the Bacteria TMDL in December 2009 and the Phosphorus TMDL in May 2013. In addition, there are updates for the pollutant load reductions associated with the revised inventory of restoration practices. As of July 2014, the County had not begun any restoration projects within the Lower Monocacy watershed.

Total Maximum Daily Loads (TMDLs) Sediment Reduction The EPA approved the Lower Monocacy TMDL for sediment in March 2009. This Plan addresses and documents sediment loading to the Lower Monocacy from the MS4 permit area of Montgomery County. It also tracks potential reduction of sediment loads through application of various watershed restoration practices. This Plan focuses on achieving the maximum practicable reductions as recommended by the state in the TMDL document. The results shown in this Plan indicate that an 80% reduction in baseline sediment load might be achieved through the maximum extent possible strategies presented. A sediment load reduction of 60.8% is required to meet the TMDL WLA. MDE indicated that the required reduction should be implemented in an iterative process that first addresses those sources with the largest impacts

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to water quality and risks to aquatic health, with consideration given to the ease of implementation and cost of implementation. Through the use of state and federal funding mechanisms and best management practices (BMPs), there is reasonable assurance that this TMDL can be implemented.

Bacterial Reduction The EPA approved Lower Monocacy TMDL for bacteria in December 2009. This Plan includes a detailed analysis for bacteria based on a calibrated fecal coliform load reduction potential associated with a full range of strategies within the Watershed Treatment Model. The Lower Monocacy bacteria TMDL is for E. Coli., and thus we have directly compared the fecal coliform results for E. Coli. The results shown in this Plan provide a general indication of the relative reduction and indicate that a 44% reduction for bacteria might be achieved through the maximum extent possible strategies presented. However, due to a high wildlife load of bacteria indicated by the model, the strategies shown do not meet bacterial load reduction of 85.4% required to meet the TMDL.

Nutrient Reduction A TMDL for phosphorus was approved for the Lower Monocacy watershed in May 2013. According to the MDE, the Lower Monocacy River phosphorus TMDL is expected to be implemented as part of a staged process recently developed by Maryland. This staged process is designed to achieve both the nutrient reductions needed within the Lower Monocacy watershed and to meet target loads consistent with the Chesapeake Bay TMDL, established by EPA in 2010 (US EPA, 2010) and scheduled for full implementation by 2025. The phosphorus load reduction results shown in this Plan indicate a 38% reduction in baseline load might be achieved through the maximum extent possible strategies presented. A phosphorus load reduction of 30% is required to meet the TMDL WLA.

Runoff Management and Impervious Cover Treatment During the five-year permit cycle, the County must add stormwater management for an additional 20% of impervious cover within the County’s MS4 permit area that is not currently managed to the maximum extent practicable (MEP). The baseline year for determining the 20% goal is 2009. There are currently 157 acres of impervious cover within the County MS4 area, 22 acres of which are treated to the MEP. Full implementation of projects identified through this implementation plan can provide control for all of the remaining 135 acres of untreated impervious cover currently not treated to the MEP. Note that the majority of these acres could be provided by alternative restoration practices such as riparian buffer reforestation, stream restoration, and street sweeping projects.

Trash and Litter Management The third major permit element is that of trash and litter management to meet the commitments in the Potomac River Watershed Trash Treaty. The County must identify trash and litter reduction measures that are being implemented towards the goal of a Trash Free Potomac. This Plan also documents trash loading from the watershed and proposed methods for mitigation.

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1.2 Existing Conditions in the Lower Monocacy Watershed

Introduction to the Lower Monocacy Watershed The Lower Monocacy River watershed is located Outreach and Stewardship Strategy in western Montgomery County. Four Ways of reaching watershed subwatersheds drain nearly 30 square miles of residents: The number of farms and agricultural businesses in the land in a southwesterly direction from the watershed leads one to the logical Damascus area towards Frederick County and assumption that there are a significant into the Monocacy River: Little Bennett Creek, number of watershed residents who Bennett Creek, Furnace Branch, and Fahrney will most likely respond to e- newsletters. Branch. Land use in this part of the County consists primarily of agriculture interspersed with many large tracts of forest. Some of the highest quality streams in the County are found here, and these serve as reference streams for the County's stream monitoring program. Other areas show evidence of having been impacted by past agricultural land use, reflected by bank instability and sedimentation problems. Stream- related improvements are taking place primarily in areas where forested buffers and best land use management practices have been implemented. A basic profile of the watershed is provided in Table 1, a map depicting existing conditions is presented in Figure 1, and a map depicting resources conditions is presented in Figure 2.

Table 1: Lower Monocacy Watershed Profile

Metric Acres Percent of Watershed Watershed Drainage Area 19,575 100% Impervious Cover 538 3% Watershed Area Subject to MS4 Permit1 1,647 8% Impervious Cover Subject to MS4 Permit1 157 10% Pervious Cover (e.g., forest, turf, meadow, farm fields)1 1,489 90% 1 Excluded areas include rural zoning, all MNCPPC lands, Federal and State property, and Federal and State roads. Forest Cover data derived from 2008 Forest Data.

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Most of the Little Bennett subwatershed is protected by County parkland, and supports a Outreach and Stewardship Strategy cold water, wild brown trout population in its Coordination among County Agencies: headwater tributaries to the north and east of Outreach and Stewardship activities Route 355. However, the naturally flashy and should be targeted to build on current low base flow nature of Little Bennett has outreach being conducted by other produced habitat and flow problems which limit county agencies such as the Soil Conservation District (SCD) and Natural it as a cold water fishery. Resources Conservation Service (NRCS) to reach the agricultural land owners. The headwaters of Bennett Creek begin near Damascus. Land use within the Bennett Creek Outreach and Stewardship Strategy Avoiding Duplication of Effort: watershed is predominantly agriculture and has To save resources and ensure consistent many large forested tracts. The underlying messaging, outreach and stewardship geology influences the streams hydrology and activities in this watershed should contributes to a naturally "flashy" stream with complement any that were previously low base flows. Despite this, it still supports a developed in the “Maryland Phase II WIP Strategies: Frederick” (MDE, 2012) and thriving cool water fish community. Much of being implemented by Frederick County Bennett Creek is within the County's Agricultural in their portions of this watershed. Preserve, where development is limited in general to large lot residential at 25 acre lots or larger.

Furnace Branch headwaters begin in western Montgomery County near Barnesville and Comus. Much of the drainage is in protected status as it is within the Monocacy Natural Resources Area or the Stronghold Sugarloaf Mountain property. Fahrney Branch starts west of Damascus near Kemptown. Much of Fahrney Branch is in the Agricultural Preserve. Fahrney Branch joins Bennett Creek in Frederick County.

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Figure 1: Existing Conditions and BMP Locations for the Lower Monocacy watershed

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Figure 2: Stream Resource Conditions for the Lower Monocacy watershed

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Watershed Land Use The MS4 Permit area covers land Outreach and Stewardship Strategy Demographic Snapshot uses in the watershed are The Watershed is dominated by single family homes displayed in Table 2. Rural and with the majority of residents’ ages between 18 and 65 forest land use is the dominant years old. In this area, outreach and education activities land use in the watershed, should be focused on these landowners.

covering about 51% of the Outreach and Stewardship Strategy watershed. This is followed by Potential Partners residential at 37% and roadway at The strength of the agricultural community in this over 5%. watershed makes it likely that the Montgomery Soil Conservation District (SCD) has an in-place communication network. The County could partner with the SCD for dissemination of outreach and education information.

Table 2: County MS4 Permit Area Land Uses in the Lower Monocacy watershed

Watershed Percent of Total Maryland Department of Planning 2002 Land Use/Land Cover Acres (%) Low Density Residential (<1 du/acre) 465 28.3% Medium Density Residential (1-4 du/acre) 143 8.7% High Density Residential (>4 du/acre) 4 0.2% Commercial 47 2.8% Industrial 17 1.0% Municipal/Institutional- Intensive1 19 1.2% Municipal/Institutional- Extensive2 18 1.1% Roadway3 86 5.3% Rural4 314 19.2% Forest5 527 32.1% Total Watershed6 1,647 100% 1 Institutional land use (churches, schools, municipal buildings) 2 Open Urban Land and Bare Rock land use (parks, cemeteries, and golf courses) 3 Combined County and private roads (excludes Federal and State roads) 4 Orchards, Vineyards, Horticulture, Feeding Operations, Cropland, Pasture, and Agricultural Buildings land use 5 From 2002 Land Use Data 6 NOTE: MDP 2002 Land Use data does not cover the entire watershed boundary

Existing Stormwater Best Management Practices (BMPs) The County currently has 65 structural stormwater BMPs within the Lower Monocacy MS4 Permit area, each capturing drainage areas that vary from several acres to less than an acre. The current inventory of County BMPs was categorized according to design era and historic performance criteria. Performance metrics were used to group the BMPs into the five categories as shown in Table 3. Currently, just over 22% of the impervious cover in the watershed is treated by a range of BMPs. More information on BMP classification and performance codes is presented in the Guidance Document, Appendix B.

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Table 3: Existing Stormwater Management for the Lower Monocacy watershed

Acres of Impervious Cover (IC) Treatment BMP Performance Code1 Count Drainage Total IC in Area Treated Drainage Area (4) Environmental Site Design (ESD) BMPs 5 18.9 0.9 (3) Effective BMPs 8 104.2 18.1 (2) Under-performing BMPs 7 44.9 3.9 (1) Non-performing BMPs 6 34.3 9.4 (0) Pretreatment and Unknown2 39 12.6 2.8 Total 65 211.6 35.1 1For drainage areas with more than one BMP, the maximum performance code was taken after deleting pretreatment BMPs (Code 0). 2Drainage area not associated with a specific BMP type

1.3 Problems Facing the Lower Monocacy Watershed

Biological and Habitat Conditions The County conducts stream biological monitoring every year resulting in the entire County being Outreach and Stewardship Strategy Potential Partners completed every five years. The most recent Assuming the high quality of the countywide, five-year monitoring cycle was streams in this watershed has led completed in 2010. In 2009, 13 tributaries in the to minimal watershed Lower Monocacy watershed were sampled for organization activity in the benthic invertebrates, fish species, and habitat in watershed, it would be useful to order to assess the stream conditions. These encourage establishment of a tributaries included Bennett Creek, Furnace watershed organization base in Branch, Fahrney Branch, and nine tributaries to this watershed for the purpose of Little Bennett Creek. Results of the survey are in future partnership planning. The County should work with Table 4, summarized by both stream miles and countywide groups such as the drainage area. The survey data can be used to Izaak Walton League (Damascus classify both instream conditions and overall chapter), Audubon Naturalist water quality from the watershed. Therefore, the Society, and Potomac Riverkeeper stream miles summary can be interpreted as an to assist with outreach and indicator of the current instream resource education activities. conditions. The drainage area summary can be used to indicate the condition of water quality draining from the watershed.

Currently, the majority of the stream resource conditions in Lower Monocacy were assessed as ‘Good’, with a few ‘Excellent’ streams. The high quality streams found in the Lower Monocacy watershed included Furnace Branch, Sopers Branch, Dark Branch, and Middle Little Bennett Creek. The Lower Monocacy received no ‘Poor’ or ‘Fair’ ratings, which in general can be attributed to the low urban development density in the watershed.

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Table 4: Lower Monocacy Stream Resource Condition Survey Results by Stream Miles and Drainage Area

Resource Condition Length (miles) % Area (Acres) % Excellent 3.6 5% 37,338 32% Good 70.7 90% 80,722 68% Fair 0.0 0% 0 0% Poor 0.0 0% 0 0% Not Accessed 3.6 5% 198 0.1% Total 77.9 100% 118,258 100%

Water Quality and Trash Issues As part of its environmental enforcement program, the County tracks citizen complaints regarding water quality and solid waste dumping. Table 5 summarizes the number and type of citizen complaints recorded for the Lower Monocacy during the ten year cycle from 2004 to 2014. Only nine cases were reported. Table 6 includes the same complaint locations summarized by general zoning type. The complaints recorded were in residential and commercial land uses. These locations were given ‘hotspot’ identification in the pollutant loading model, discussed further in Section 3.

Table 5: Recorded Water Quality Complaints1 in the Lower Monocacy watershed

Number by Water Quality Complaint Type Total Stormwater- Surface Overflows Surface Water- Assistance # of Pollutant Water- Petroleum Requested cases Discharge Chemical Product Discoloration/ in Water Unknown 9 2 1 1 2 3 1 From CaseBase_March2014.shp

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Table 6: Water Quality Complaint by Zoning1 in the Lower Monocacy watershed

General Zoning Type2 Acres Total # of Properties Residential 3.6 3 Commercial 0.0 0 Industrial 0.0 0 Unzoned 59.3 6 1 From CaseBase_March2014.shp 2 From County PROPERTIES.shp

Solid waste trash dumping sites were also logged by the County to identify trash Outreach and Stewardship Strategy hotspots, similar to the water quality Education Project: complaint database. The results of the To reduce trash hot spots, stakeholder outreach is recommended in partnership monitoring are limited to cases of illegal with HOAs, County recycling offices and dumping in the watershed. Table 7 athletic organizations. Educating includes a summary of the complaint watershed residents on the importance of database by complaint type. There were 16 proper trash can maintenance, keeping playing fields clean, and dumpster total complaints. Table 8 identifies the maintenance is recommended for success. general zoning type at the site of the Implementation details are in the Practice complaint. Two of the complaints were Sheet entitled Anti-littering Outreach and recorded as residential dumping and one as Stewardship Campaign. public land (industrial zoning type).

Table 7: Solid Waste Trash Dumping Sites1 in the Lower Monocacy watershed

Number per Solid Waste Type Total Farm Residential Public Dumpster # of Land Land cases 16 4 3 8 1 1 From CaseBase_March2014.shp

Table 8: Solid Waste Trash Dumping Sites by Zoning1 in the Lower Monocacy watershed

General Zoning Type2 Acres Total # of Properties Residential 2.9 1 Commercial 0.3 1 Unzoned 42.4 7 1 From CaseBase_March2014.shp 2 From County PROPERTIES.shp

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1.4 Existing Pollutant Loads and Impervious Surfaces

Sediment Loads EPA approved the “Total Maximum Daily Load of Sediment in the Lower Monocacy River Watershed, Frederick, Carroll, and Montgomery Counties, Maryland” Final Report in March 2009. This document establishes a TMDL for sediment for the Montgomery County MS4 Permit area within the Lower Monocacy watershed. The baseline load and wasteload allocation (WLA) for the MS4 Permit area are displayed in Table 9. It is important to note that the Lower Monocacy stormwater WLA was distributed based on the proportion of 2000 Maryland Department of Planning (MDP) developed land use classification of impervious and pervious areas within the total applicable 2000 Chesapeake Bay Program urban land use (MDE, 2010a). The resulting land use distribution differed significantly from the 2002 MDP land use model used for the Countywide Coordinated Implementation Strategy (CCIS). The difference became an important factor in establishing a baseline load, predicting sediment load reduction, and tracking progress toward meeting the TMDL. For the purpose of modeling pollution reduction strategies, it was necessary to establish a rough calibration between the 2002 MDP land use loads and the MDE generated WLAs for the Lower Monocacy.

Table 9: TMDL Baseline Loading Estimates for Lower Monocacy watershed and Comparison Values from MDE

Target Montgomery Baseline Montgomery Montgomery TMDL Parameter Issue Date County WLA % County MS4 load County MS4 Reduction load Sediment 2009 172.2 tons/yr 60.8% 67.5 Bacteria 2009 67,452 Billion MPN/yr 85.4% 9,848 Phosphorus 2013 1,872 lbs/yr 30% 1,305

Bacterial Loads MDE prepared the “Total Maximum Daily Load of Fecal Bacteria for the Lower Monocacy River Basin in Carroll, Frederick, and Montgomery Counties, Maryland” Final Report in September 2009. This document establishes a TMDL for the Montgomery County MS4 Permit area within the Lower Monocacy watershed. The baseline load and wasteload allocation (WLA) for the MS4 Permit area are displayed in Table 9. The Lower Monocacy bacteria TMDL is for E. Coli. Because this Implementation Plan analysis of the Lower Monocacy was presented for fecal coliform as a default capability of the Watershed Treatment Model, these fecal coliform results were directly compared to E. Coli. The correlation between the WTM and MDE baseline load was within 11%.

Nutrient Loads MDE prepared the “Total Maximum Daily Load of Phosphorus in the Lower Monocacy River Watershed in Frederick, Carroll, and Montgomery Counties, Maryland” Final Report in August 2012. This document establishes a TMDL for the Montgomery County MS4 Permit area within the Lower Monocacy watershed. The baseline load and wasteload allocation (WLA) for the MS4 Permit area are displayed in Table 9. This TMDL is in conjunction with the nutrient WLAs for the Bay-wide nutrient TMDL established in 2011. This Plan estimates the load reductions from a baseline condition for phosphorus, which was calibrated with the MDE baseline load.

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Impervious Surfaces Impervious cover in the watershed, as derived from County GIS, is summarized in Table 10. Transportation-related surfaces (roads) account for the largest percentage of impervious cover in the watershed at 55%. 16.2% of roads are designated as Low Density Residential, which are typically an open section road and easily retrofit using ESD stormwater best management practices. The rooftops of single family homes account for the second largest impervious surface at just over 19.5%.

Table 10: MS4 Permit Area Impervious Cover

Impervious Cover Type Impervious Acres Watershed (%) 1. Roads a. Low Density Residential1 25.5 16.2% b. Other2 61.0 38.8% 2. Parking Lot a. County Small Lots (<1 acre) 3 1.0 0.6% b. County Large Lots (>=1 acre) 3 1.5 1.0% c. Private 24.5 15.6% 3. Roofs a. County4 2.0 1.3% b. Single Family Homes5 30.7 19.5% c. Other 9.2 5.8% 4. Sidewalks6 0.7 0.4% 5. Other a. Schools7 2.8 1.8% b. Recreational8 1.3 0.8% Total Impervious Acres from GIS9 157.3 100% 1All roads in RE2 or R200 property zoning. 2Includes County and private roads. 3Parking lots located in County-owned parcels, derived using County_pnts from the County’s PROPERTY geodatabase. 4Buildings located in County-owned parcels, derived using County_pnts from the County’s PROPERTY geodatabase. 5Buildings located on single family home parcels, derived using MDP_pnts from the County’s PROPERTY geodatabase and selecting only single-family dwelling types. 6Sidewalks in jurisdiction. Does not include all residential sidewalks or driveways. 7Impervious cover located in public school parcels, derived using pubsch points from the County’s LOCATIONS geodatabase. Some overlap with other impervious. 8 Impervious cover identified as Recreational in geodatabase. Some overlap with other impervious. 9 Sum of all GIS impervious. Excludes overlaps in schools and recreational.

Existing Trash Loads The Potomac River Watershed Trash Treaty outlines the agreement between local and state elected officials to commit to a Trash Free Potomac. The agreement includes three major commitments:

• Support and implement regional strategies aimed at reducing trash and increasing recycling;

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• Increase education and awareness of the trash issue throughout the Potomac watershed; and • Reconvene annually to discuss and evaluate measures and actions addressing trash reduction.

In general, trash reduction strategies fall into four categories: (1) Structural; (2) Educational; (3) Municipal; and (4) Enforcement. Structural stormwater BMPs are generally assigned 95% removal credit for trash from the contributing drainage area. BMPs, while not specifically designed to capture trash, are also not very good at passing trash, and debris is prone to build up in forebays, around plants and interior elements, and around the outlet structures.

In addition to trash removal by structural stormwater BMPs, programmatic practices from the other three categories (i.e., educational, municipal, and enforcement) provide trash prevention and control. These programmatic practices are specially aimed at reducing trash inputs to roads and streams, including educationally focused programs such as reduce, reuse and recycle campaigns; dumpster management and storm drain marking; and programs tied to operations such as littering and illegal dumping enforcement; stream cleanups; and street sweeping. These programmatic practices are further explored in the countywide strategy.

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2 Inventory of Provisional Restoration Candidates

2.1 Types of Restoration Practices

Table 11 summarizes the 11 groups of watershed restoration practices evaluated for the Lower Monocacy watershed. The first four groups of restoration practices involve various forms of ESD. All restoration practices differ in the mode and manner by which they will be delivered in the watershed (capital budgets, operating budgets, regulation, etc.). Multiple delivery mechanisms are needed to implement enough watershed restoration practices to meet the stringent watershed treatment and pollutant reduction targets set forth in the County’s MS4 permit, the TMDL and the Potomac River Watershed Trash Treaty.

Table 11: Restoration Practices to be Evaluated in Watershed Implementation Plans

Description of Practice Application in the Lower Monocacy Watershed ESD Practices New ESD Retrofit Practices - These include small scale ESD practices Public ESD applied to County- owned or privately owned buildings, streets and Retrofits parking lots and rights of way. Examples include rainwater harvesting, green roofs, upland reforestation, soil compost amendments, rooftop disconnection, “green street” retrofits, and converting swales to dry swales. ESD Upgrades - This category includes retrofit ESD practices within Code 1 and 2 BMP existing publicly-owned or privately-owned stormwater infrastructure, so Upgrades that their hydrologic and pollutant reduction performance is upgraded. (see WTM 3.0) Impervious Cover Reduction - This category involves cases where un- Not applicable needed impervious cover is removed, soils amended and vegetation restored primarily on County schools, streets and parking lots Voluntary LID Implementation - ESD practices that are installed as a result Private ESD of County education and incentive programs. Retrofits Programmatic and Operational Practices MS4 Programmatic Practices – This category deals with reduced Lawn Care pollutants that can be attributed and quantified through MS4 stormwater Education and Pet education (e.g., lawn care), pollution prevention improvements at Waste Education municipal hotspots, and better housekeeping on County land and facilities. Also includes any pollutant reductions due to product substitution, such as imposing restrictions on N or P content in fertilizer, increased pet waste enforcement, trash prevention and control. Hotspot Pollution Prevention – This category credits enhanced structural Not applicable and non-structural practices employed at non-publicly owned stormwater hotspots that are identified through land use analysis. Enhanced County Street Sweeping - This category includes any pollutant DOT Countywide reduction that can be attributed to more intensive and targeted street Street Sweeping sweeping in the watershed conducted by the County.

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Description of Practice Application in the Lower Monocacy Watershed Trash Prevention and Control - This category includes a wide range of Not applicable programs and practices specially aimed at reducing trash inputs to stream, including reduce, reuse and recycle campaigns, littering and illegal dumping enforcement, dumpster management, storm drain marking, storm drain inlet devices, stream cleanups, instream controls to trap and remove trash, etc. These measures are in addition to any trash trapped and removed by other restoration practices which are computed separately. Structural Practices Traditional Retrofits - This is the traditional retrofit scale where large- Not applicable scale, non-ESD retrofits are constructed on larger parcels of public or private land as discovered through analysis of County's BMP inventory. BMP Maintenance Upgrades - Credit for improvement in current permit Code 1 and 2 BMP cycle for major maintenance upgrades of failed stormwater practices that Upgrades result in significant improvement in hydraulic function and increased (see WTM 3.0) treatment capacity using existing County maintenance budget. Credit can only be taken for increased load reduction due to upgrades that significantly rehabilitate BMP function from its installation baseline. (e.g., increase capacity, lengthen flow path, reduce short-circuiting, eliminate design failures). Habitat Restoration - This category includes any pollutant reduction or Stream Restoration volume reduction that can be attributed to specific stream restoration or and Riparian riparian reforestation projects planned for construction in the watershed Reforestation for the permit cycle.

2.2 Inventory of Previously Identified Projects

Potential restoration strategies for the Lower Monocacy watershed set forth in this Plan were drawn from the County’s restoration sites database (March 2013) and retrofit reconnaissance investigations performed in September 2013. Previously identified restoration projects identified are presented in Figure 3.

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Figure 3: Identified Restoration Opportunity Locations for the Lower Monocacy watershed

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3 Evaluation of the Restoration Strategies to Meet MS4 Permit and TMDL Requirement

3.1 Pollutant Load Tracking MDE established the TMDL for sediment in the Lower Monocacy using and the 2000 Chesapeake Bay Program (CBP) land use model with a BMP factor based on a 2005 BMP database and daily time series of discharge from 1985 to 2005.

The bacteria TMDL was determined by estimating a baseline load from current monitoring data. The baseline load is estimated using long-term geometric mean and weighting factors from the flow duration curve. The TMDL for fecal bacteria entering the Lower Monocacy River is established after considering three different hydrological conditions: high flow and low flow annual conditions, and an average seasonal condition when water contact recreation is ore prevalent. The allowable load is reported in units of Most Probable Number (MPN) per day.

Lastly, the data solicitation for phosphorus was conducted by MDE in November 2009, and readily available data from 1998 up to the time of data solicitation. The objective of the phosphorus TMDL was to establish phosphorus loads that will be protective of the Aquatic Life Use designation for the Lower Monocacy River watershed. Currently in Maryland, there are no specific numeric criteria that quantify the impact of phosphorus on the aquatic health of non- tidal stream systems. Therefore, a reference watershed TMDL approach was used to establish a phosphorus loading threshold. The CBP Phase 5.3.2 Model was used to determine the nutrient loads in the Lower Monocacy River and the reference watersheds.

The point source WLA for the Montgomery County MS4 Permit area was determined using distributed land use. MDE used the Maryland Department of Planning (MDP) 2000 land use/land cover information. A similar land use-based model was used in this Plan to develop a primary source load of sediment, nutrients, bacteria and trash to Lower Monocacy using 2002 MDP land use data for consistency with the countywide implementation strategy. Further information on land use loading rates can be found in the Plan Guidance Document, Section 2.

3.2 Desktop Review of BMP Coverage A desktop review of BMP coverage was used to analyze the existing BMP coverage in Lower Monocacy. The BMPs were classified according to their performance code as shown in Table 12. The relative performance of each practice type was based on national comparative reviews of pollutant reduction and runoff reduction performances of practices or performance studies on individual practices as described in the Guidance Document, Section 3 (CSN, 2011). The composite efficiencies were also compared to recent research values and assumptions used in local models (USACE, 2008; Chesapeake Bay Program, 2008; and MDE, 2009) to further justify the performance coding. A summary of the BMP modeling assumptions are in Table 12.

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Table 12: Composite Runoff Reduction, Effectiveness Factor, and Pollutant Reduction by BMP Performance Code

Performance Description TSS1 TN2 TP3 (%) F Col4 DF5 Code (%) (%) (%) (%) 0 Pretreatment BMPs 20 5 5 10 0.15 1 Non-performing BMPs 5 0 0 0 0.05 2 Underperforming BMPs 20 5 5 10 0.15 3 Effective BMPs 80 40 50 65 0.75 4 ESD Practices 90 65 65 75 1.0 1 Total Suspended Solids 2 Total Nitrogen 3 Total Phosphorus 4 Fecal Coliform 5 Discount Factor

3.3 Summary of Watershed Treatment Model Scenarios The Watershed Treatment Model (WTM) was used to estimate pollutant sources and treatment options for Lower Monocacy. The spreadsheet used was an updated version of the publically available v3.1, which included an expanded runoff volume reduction component (personal correspondence, Deb Caraco, 2009). The WTM was used to track a progression of restoration strategies across the watershed to illustrate the effectiveness of each strategy in reducing pollutant loads and ultimately meeting the TMDL load reduction targets. Targeted strategies range from specific stormwater management initiatives identified by the County to less well defined nonstructural strategies tied to stakeholder participation and involvement.

A summary of the model scenarios evaluated using the Watershed Treatment Model are provided in the table below and described in more detail in the following sections.

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Table 13: Summary of WTM Scenarios

Implementation Phase Description The WTM was run under existing conditions approach with the MDP year 2002 land use/land cover data and existing WTM Baseline Conditions BMPs. A rough calibration to the MDE TMDL baseline load was conducted. WTM 2.0 Completed, In Design, These practices cover new ponds, retrofits of existing BMPs, or In Construction as of 2013; and ESD practices from the County’s proposed projects list High Priority projects; and and sites identified in the watershed pre-assessment. Other Potential Projects The remaining inventory of BMPs, which have reduced treatment efficiency, were reviewed for retrofit opportunities and potential increased pollutant reduction WTM 3.0 ESD Strategies and efficiencies. In addition, the County’s inventory for other Other Structural BMPs project types that include public properties (e.g., libraries and parking lots), public schools, and open section roads available for ESD retrofits was reviewed as were areas for private property ESD retrofits. Other projects on public lands and other practices that are identified in Appendix B of the Guidance Document were WTM 4.0 Habitat Restoration explored. For Lower Monocacy this focused on habitat restoration related to riparian buffer reforestation and stream restoration. Other MS4 programmatic practices that are identified in Appendix B of the Guidance Document were examined. For WTM 5.0 MS4 Programmatic Lower Monocacy, this included street sweeping, lawn care Practices education, and pet waste education to target the TMDL pollutants.

WTM 1.0 – Baseline Conditions The WTM was run under existing conditions approach with the MDP year 2002 land use/land cover data (Table 2) and existing BMPs coded under “Existing Management Practices” (Tables 14-17). The baseline pollutant load was calculated and compared to the MDE-determined baseline MS4 load for the pollutants of concern. Since the data used to establish the sediment TMDL was based on model simulations using 2000 BMP data, any BMPs with “approved” dates after 2000 could be counted towards meeting the TMDL reduction target. Therefore, the BMP inventory used to set the baseline sediment load is shown in Table 14.

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Table 14: BMP Inventory for Lower Monocacy through 2000

BMP Performance Total DA Total IA Category Count (Acres) (Acres) ESD Practices (Code 4) 3 1.4 0.9 Effective BMPS (Code 3) 5 83.0 17.7 Underperforming BMPs (Code 2) 0 - - Non-performing BMPs (Code 1) 2 5.4 3.6 Pretreatment BMPs (Code 0) 2 2.8 2.4 DA: Drainage Area IA: Impervious Area

The fecal bacteria TMDL model was based on water sampling in 2003-2004, so the BMPs included in the WTM baseline model for bacteria included all BMPs approved through 2004, as shown in Table 15.

Table 15: BMP Inventory for Lower Monocacy through 2004

BMP Performance Total DA Total IA Category Count (Acres) (Acres) ESD Practices (Code 4) 3 18.9 0.9 Effective BMPS (Code 3) 5 83.0 17.7 Underperforming BMPs (Code 2) 6 30.3 3.6 Non-performing BMPs (Code 1) 3 6.6 4.4 Pretreatment BMPs (Code 0) 2 2.8 2.4 DA: Drainage Area IA: Impervious Area

The phosphorus TMDL model was based on simulations of the river in 2009, so the BMPs included in the WTM baseline model for phosphorus included all BMPs approved through 2009, as shown in Table 16.

Table 16: BMP Inventory for Lower Monocacy through 2009

BMP Performance Total DA Total IA Category Count (Acres) (Acres) ESD Practices (Code 4) 3 18.9 0.9 Effective BMPS (Code 3) 6 104.2 18.1 Underperforming BMPs (Code 2) 7 44.9 3.9 Non-performing BMPs (Code 1) 6 34.3 9.4 Pretreatment BMPs (Code 0) 3 9.3 2.8 DA: Drainage Area IA: Impervious Area

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The complete inventory of BMPs for Lower Monocacy is shown in Table 17.

Table 17: All Existing BMP Inventory for Lower Monocacy

BMP Performance Total DA Total IA Category Count (Acres) (Acres) ESD Practices (Code 4) 5 18.9 0.9 Effective BMPS (Code 3) 8 104.2 18.1 Underperforming BMPs (Code 2) 7 44.9 3.9 Non-performing BMPs (Code 1) 6 34.3 9.4 Pretreatment BMPs (Code 0) 3 9.3 2.8 DA: Drainage Area IA: Impervious Area

WTM 2.0 – Completed, In Design, and In Construction Projects, High Priority Projects, and Other Potential Retrofit Projects The WTM was run with a series of future management practices for Lower Monocacy, which were proposed projects from the County inventory of restoration sites from 2013 and field sites identified during the watershed pre-assessment. The County currently has one planned future management practice within the Lower Monocacy watershed from the County’s 2013 restoration sites database of potential projects. Six high priority projects were identified during the pre-assessment phase. These practices cover new ponds, retrofits of existing BMPs, and ESD projects from the proposed projects as summarized in Table 18. Drainage area (DA), impervious area (IA), total length, and total cost will be determined from engineering designs or estimated based on the running average per practice values from the County database. In general, the County will use the following to estimate proposed impervious area and costs, where engineering costs are unavailable:

Table 18: Three levels of treatment: Completed, In Design, or In Construction; High Priority; and Other Potential Projects

Total Total Length Total DA Total IA Restoration Type Count Cost (mi) (acres) (acres) Completed, In Design, or In Construction None High Priority Sites ESD 5 $2,424,685 - 75.50 11.87 New Pond 1 $205,500 - 2.30 1.50 Other Potential Projects ESD 1 $154,000 - 0.77 0.77

The cumulative pollutant load reduction will be computed and compared to the TMDL annual target for sediment, fecal bacteria, and phosphorus. The applicable target reduction from the calculated MDE stormwater WLA is 60.8% for sediment, 85.4% for bacteria, and 30.0% for phosphorus. Thus, this step will determine how far and at what cost these projects go toward meeting the TMDLs, impervious cover, trash and other pollutant reduction goals. New Ponds were given effective BMP pollutant reduction efficiency, and ESD practices were given full ESD pollutant reduction efficiency.

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Retrofits of existing BMPs were reconciled with the existing urban BMP database and given an incremental increase in pollutant reduction efficiency based on an assumed Code 4 BMP efficiency. The actual drainage area and impervious area from the existing practice was used to calculate pollutant and runoff reduction. In general, the County used the information in Table 19 below to estimate proposed impervious area and costs, where engineering costs were unavailable:

Table 19: Impervious Cover and Cost Estimates used in the Future Management Scenarios

• 38% imperviousness per drainage acre • New Ponds, $6,000 per drainage acre • Retrofit Pond, $4,000 per drainage acre • ESD project, $200,000 per impervious acre • Wetland, $50,000 per drainage acre

WTM 3.0 – ESD Strategies and Other Structural BMPs The remaining inventory of Code 1 and 2 BMPs, which have reduced treatment efficiency, were reviewed for retrofit opportunities and potential increased pollutant reduction efficiencies. In addition, the potential for other project types that include public properties (e.g., libraries), public schools, and open section roads available for ESD retrofits was reviewed. Finally, the potential for ESD implementation on private properties was explored. The Guidance Document was followed for determining total potential reduction from assumed treatment areas from these four target areas.

a. Code 1 and 2 BMP ESD Retrofits- The remaining Code 1 and Code 2 BMP treatment area was calculated by subtracting the previously targeted retrofits from (WTM 2.0) from the total BMP area (summarized in Table 20). It was then assumed these areas were suitable for retrofits and incrementally increased the performance efficiency of Code 1 and 2 BMPs to the MEP within Future Management Practices. The cost per impervious acre estimate was based on typical County retrofits for large pond BMPs.

Table 20: Underperforming (Code 2) and Non-performing (Code 1) BMPs targeted for retrofit

Target Count Total DA Total IA Cost Total (acres) (acres) per IA Cost Total Code 2 for Retrofit 7 44.9 3.9 $67,500 $261,900 Total Code 1 for Retrofit 6 34.3 9.4 $67,500 $635,850 Total $897,750

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Table 21 shows the following: Outreach and Stewardship Strategy b. Public properties – Seventy- Education Project: To reduce stormwater pollution on private five percent of the impervious property, stakeholder outreach is cover from the aggregate area recommended explaining the need for and associated watershed stakeholders to capture some imperviousness from of the precipitation that falls on their roof untreated County-owned and allow for groundwater recharge hence slowing the flow of surface waters and Large Parking Lots was potential erosion impacts. It is assigned to future recommended that this can be management practices as accomplished by expanding existing code 4 (see Table B.5 of County programs similar to RainScapes, in the Damascus and Kemptown areas as Guidance Document, and described in the Practice Sheet entitled summary in Table 21 below). Roof Runoff Reduction Outreach and In addition, thirty percent of Stewardship Campaign. County-owned Rooftops was targeted for retrofit. The targets for restoration was based on a judgment of the maximum extent practicable considering physical constraints to ESD/LID. The unit cost estimate was based on an equal mix of new ESD retrofits for larger parking lots and rooftops.

c. Public schools – Thirty percent of the impervious cover from the aggregate area and associated imperviousness and from untreated Public Schools Parcels was assigned to future management practices as code 4 (see Table B.5 of Guidance Document, and summary in Table 21 below). The restoration target was set similarly to part (b) above.

d. Low Density Residential (LDR) and Other County Roads - Fifty Outreach and Stewardship Strategy percent of the impervious cover This watershed has relatively few from the aggregate area and churches, schools and commercial districts making targeted partnership associated imperviousness goals of 50% or higher easier to achieve. from RE2 and R200 roadways Organizations to partner with in this was assigned to future watershed include: churches such as management practices as code Hyattstown Christian, Bethesda United Methodist, The Wesleyan, Mountain 4 (see Table B.5 of Guidance View United Methodist, Pleasant Grove, Document, and summary in St. Annes, Damascus Methodist and Table 21 below). The Damascus United Methodist; restoration target was set Commercial districts such as Damascus similarly to part (b) above. The Center Shopping Center and Ridgeview Center Shopping Center; fire stations unit cost estimation was based such as Damascus Volunteer Fire on an open-section road Department; and schools such as John T. retrofit. Other County Roads Baker Middle School, Damascus High were assigned a forty percent School, and Damascus Elementary. aggregate impervious cover restoration target, and the unit cost was based on a curbed road retrofit.

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e. Private Property ESD implementation - The approach is similar to the County's RainScapes program which provides financial incentives for adding ESD practices on private property. Neighborhoods in Lower Monocacy watershed to be assessed were selected based on criteria associated with home ownership, existing neighborhood treatment, existing home owner’s association and lot size. As shown in Figure 4, there was only one neighborhood, Spring Garden Estates, was selected to be assessed in the Lower Monocacy watershed. This selected neighborhood was assessed in the field by staff the summer of 2013 using criteria developed by the County’s RainScapes program to determine if front yards were appropriate for various ESD practices (Figure 4). Spring Garden Estates, the only assessed neighborhood, was targeted for use in the WTM 3.0 and fifteen percent implementation of site-scale ESD projects was assumed. Table B.8 of the Guidance Document describes the basic approach used to make pollutant reduction and cost decisions.

Table 21: Summary of Other structural and ESD retrofit restoration potential within County owned facilities, schools, and roads options

Total Restoration Restored Unit Restoration Land Cover IA Potential* IA Cost** Cost* Type Acres % Acres $/Acre IA $ County Large 1.5 75% 1.10 $140,395 $153,733 Parking Lots1 County Roofs2 2.0 30% 0.59 $56,438 $33,168 Schools3 2.8 30% 0.84 $140,395 $118,479 Low Density Residential 21.17 50% 11.83 $34,563 $365,844 Roads4 Other County 55.74 40% 21.30 $80,500 $1,794,828 Roads Residential Properties: 15.3 15% 2.3 $103,926 $238,510 Priority Neighborhoods5 Totals 98.4 38.0 $2,704,562 * Restoration target was based on a judgment of the maximum extent practicable considering physical constraints to ESD/LID **Unit Cost was derived from an equal mix of green roofs, cisterns, permeable paving, and bioretention BMPs according to the Guidance Document. 1 Parking lots located in County-owned parcels, derived using County_pnts from the County’s PROPERTY geodatabase. 2 Buildings located in County-owned parcels, derived using County_pnts from the County’s PROPERTY geodatabase. 3 Impervious cover located in public school parcels, derived using pubsch points from the County’s LOCATIONS geodatabase. Some overlap with other impervious. 4 All roads in RE2 or R200 property zoning. 5 Rooftop area in High and Medium Priority Neighborhoods

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Figure 4: Assessed and Targeted Neighborhoods for the Lower Monocacy watershed

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WTM 4.0 – Habitat Restoration Other projects on public lands and other practices that are identified in Appendix B of the Guidance Document were explored. For the Lower Monocacy watershed, the focus of this was the reduction of the sediment, fecal bacteria, and phosphorus loads.

a. Habitat restoration (riparian reforestation) – The total amount of unforested 100-ft buffer along streams was computed and then the land use area was converted to forest area in Future Management Practices (see Table B.14 of the Guidance Document, and summary of areas in Table 22 below). One-hundred percent implementation of riparian reforestation across the total area was assumed.

Table 22: Summary of land use categories within the 100-ft buffer area of County streams.

Watershed Total Buffer Area MdOP 2002 Land Cover/Land Use Unforested Area Forested Area Acres (acres) (acres) Low Density Residential 466 33.1 17.8 Medium Density Residential 141 4.5 1.3 Roadway 86 10.4 0.2 Commercial 45 0.6 0.1 Industrial 17 1.6 0.0 Municipal/Institutional- Extensive 18 4.6 0.2 Rural 314 35.9 3.8 Total Watershed1 1,647 90.7 24.5 Total Cost2 $2.25 Million 1 Includes additional areas, not shown, including forested areas not targeted for riparian reforestation 2 Assumes $33k per acre reforestation

b. Habitat restoration (stream restoration) – The sediment load contribution from stream bank erosion can be highly variable according to research. Literature values for the watershed sediment load contribution from instream sources vary from 60% (Mukundan, et al., 2010), to 90% (Rosgen, 2006) and anywhere from 5-80% (Evans, et al., 2003). Stream restoration can be an effective tool for both instream sediment source stabilization and habitat restoration. However, the efficiency of stream restoration at reducing pollutants is also highly variable. Table 17 summarizes the published reduction efficiencies from the Chesapeake Bay Program, MDE (2009), and Guidance Document. The Guidance Document data was largely based on data from highly urbanized Baltimore City streams (BDPW, 2006). The sediment TMDL documentation links aquatic health directly to sediment pollution, thus the following potential pollutant reduction efficiencies were assigned to the County streams according to their biological monitoring results. Since all of the streams in Lower Monocacy are rated as Good and Excellent, we used the CBP reduction efficiencies.

To establish a reasonable initial planning approach, data from the County's geographical information system (GIS) was used to quantify the poorly buffered stream length from Table 23 and identify these reaches for potential

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restoration. The total length of poorly buffered streams in the watershed is 29,375 feet, or approximately 7% of the total stream length. In general, the County will not pursue stream restoration on good quality reaches unless there is field verification that existing conditions may be degraded if protective measures are not taken.

Table 23: Potential pollutant reduction efficiencies for stream restoration

IBI SCORE TN TP TSS SOURCE

NARRATIVE lbs/linear foot lbs/linear foot lbs/linear foot GOOD 0.02 0.0035 2.55 MDE, 2011 FAIR 0.2 0.011 3.58 PG County, 2010 POOR 0.2 0.068 310 CBP, 2013

WTM 5.0 – Programmatic Practices Other MS4 programmatic practices that are identified in Appendix B.8 of the Guidance Document were examined. For Lower Monocacy, this included to street sweeping, lawn care education, and pet waste education to target the TMDL pollutants of sediment, phosphorus, and bacteria.

For street sweeping, the potential reduction in load was calculated using the County’s data set on street sweeping from the countywide street sweeping program from 2007-2009. The potential load reduction from street sweeping is shown in Table 24.

Table 24: MS4 Programmatic Practices

Potential Sediment Strategy Road Miles Unit Cost Total Cost Source (tons/yr) Street Sweeping 34.2 7.0 $2,420 per ton $ 16,940

The potential reduction in load from Lawn Care and Pet Waste Education was calculated using the WTM, which requires the number of acres of lawn and total number of dwellings in the watershed. Default WTM discounts based on residential surveys assume that 80% of lawn areas are fertilized, 65% of those areas are “over fertilized,” and 70% of owners would be willing to change their behavior. Default WTM discounts for pet waste include an assumed 40% of households with dogs, 50% of owners who walk their dogs, 60% of owners who currently clean up after their pets, and 60% of owners willing to change their behavior.

We assumed a high fraction (0.8) of the population could be targeted with effective educational messages, which for Lower Monocacy included every household within the watershed at a cost of $15 per household. The potential load reductions from the residential education program are shown in Table 25 (Schueler 2005 – USRM #2 Table 47).

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Table 25: MS4 Programmatic Practices in Lower Monocacy

Potential Potential Phosphorus Bacterial Unit Total Strategy Units Reduction Reduction Cost Cost (lbs/yr) (Billion #/yr) Lawn Care 475 lawn acres 178 N/A $15 per du $11,655 Pet Waste 777 dwellings 272 97,805

The County should document and collect information from all pet waste removal companies to identify how much pet waste is being collected and disposed of properly. As part of this documentation, there should be incentives provided to residents to use these pet waste removal companies, purchasing/using pet waste bags, and incentives to HOA’s to install and maintain pet waste trash receptacles with plastic bags. Incentives should be provided to lawn care companies to reduce the over fertilizing of lawns.

3.4 Preliminary Results of the Sediment, Bacteria and Phosphorus Load Reduction Analysis

The WTM was run iteratively using a series of spreadsheets for each step outlined above. Initially, the WTM was coded with the existing land use and BMP database to calculate the baseline load. This was within 5% of the MDE baseline for sediment; 11% of the baseline for E Coli; and 25% of the baseline for Phosphorus, after adjustment for the County MS4 Permit area and phosphorus loading rate assumptions.

The percent reduction in pollutants was computed using our WTM baseline load to track restoration efforts against the targeted stormwater WLA reduction for sediment (60.8%). From there, the iterative approach was used to track progress toward meeting the sediment WLA as shown in Table 26. As indicated previously, stream restoration was modeled outside of the WTM as a standalone practice, which is why it is shown out of order in Table 26.

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Table 26: Preliminary Results of WTM Modeling for Sediment

Sediment Cumulative Implementation Loading Cost Comments Phase % reduction Million $ from baseline WTM Baseline 0% Normalized to MDE Baseline Load $- 11% High Priority and Other Potential Retrofit $2.78 WTM 2.0 Projects WTM 3.0 16% ESD Strategies and Other Structural BMPs $3.68 WTM 3.0 23% Underperforming BMP Retrofits $6.15 WTM 3.0 24% Priority Neighborhoods ESD Retrofits $6.39 WTM 3.0 26% Riparian Buffer Reforestation $8.63 WTM 4.0 32% Street Sweeping $8.65 WTM 5.0 32% Lawn Care Education $8.66 WTM 5.0 32% Pet Waste Education $8.67 WTM 4.0 80% Stream Restoration $36.39 TMDL WLA 60.8% Waste Load Allocation

The restoration strategy is further illustrated in Figure 5, where the implementation phases are shown in order with their resulting sediment load in comparison to the WLA. The cost for each implementation phase is also shown.

Figure 5: Sediment loading over restoration implementation phase

The restoration implementation strategy should be geared to target the sources of sediment. Based on the results of the modeling, street sweeping, retrofits of underperforming BMPs and

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structural stormwater practices were the most economically efficient practices for meeting the Outreach and Stewardship Strategy sediment load reduction requirements. From a Education Project: cost perspective, stream restoration was not the To encourage stream restoration on private property, stakeholder outreach most cost effective strategies for meeting the is recommended on the important TMDL requirement. However, the total sediment roles of protecting streams on private reduction from stream restoration practices property. This could be a good 4-H result in greater sediment reduction (Table 27). project for 4-H members in this watershed, or a good recruitment event for a countywide watershed organization. Implementation details are contained in the Practice Sheet entitled Riparian Reforestation Outreach and Stewardship Campaign.

Table 27: Individual restoration strategy cost effectiveness for sediment load reduction

Sediment Incremental Unit Cost Rank Restoration Strategy reduction Cost tons/year Million $ ton/Million $ 1 Street Sweeping 7 $0.02 413 2 Retrofit of Underperforming BMPs 6 $0.90 6 3 Other Structural BMPs and ESD Strategies 19 $5.25 4 4 Priority Neighborhoods ESD Retrofits 0.7 $0.24 3 5 Stream Restoration 55 $27.72 2 6 Riparian Reforestation 2.1 $2.25 0.9 7 Pet Waste Education - $0.01 0 8 Lawn Care Education - $0.01 0

The percent reduction in bacteria was computed using our WTM baseline load to track restoration efforts against the targeted stormwater WLA reduction for E Coli (85.4%). From there, the iterative approach was used to track progress toward meeting the bacteria WLA as shown in Table 28.

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Table 28: Preliminary Results of WTM Modeling for Bacteria

Bacteria Cumulative Implementation Loading Cost Comments Phase % reduction Million $ from baseline WTM Baseline 0% Normalized to MDE Baseline Load $- WTM 2.0 10% High Priority and Other Potential Projects $2.78 WTM 3.0 16% ESD Strategies and Other Structural BMPs $3.68 WTM 3.0 23% Underperforming BMP Retrofits $6.15 WTM 3.0 24% Priority Neighborhoods ESD Retrofits $6.39 WTM 3.0 28% Riparian Buffer Reforestation $8.63 WTM 4.0 28% Street Sweeping $8.65 WTM 5.0 28% Lawn Care Education $8.66 WTM 5.0 44% Pet Waste Education $8.67 WTM 4.0 44% Stream Restoration $36.39 TMDL WLA 85.4% Waste Load Allocation

The restoration strategy is further illustrated in Figure 56, where the implementation phases are shown in order with their resulting bacterial load in comparison to the WLA. The cost for each implementation phase is also shown.

Figure 6: Bacterial loading over restoration implementation phase

Based on the results of the modeling, pet waste education, retrofits of underperforming BMPs were the most economically efficient practices for meeting the bacterial load reduction

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requirements. From a cost perspective, structural stormwater practices, RainScapes, and riparian reforestation are not the most cost effective strategies for meeting the TMDL requirement. Rather, the programmatic practices are more cost effective, and result in greater bacterial reduction (Table 29).

Table 29: Individual restoration strategy cost effectiveness for bacterial load reduction

Bacterial Incremental Unit Cost reduction Cost Rank Restoration Strategy Billion Million $ Billion #/Million $ #/year 1 Pet Waste Education 9,389 $0.01 805,604 2 Retrofit of Underperforming BMPs 3,270 $0.90 3,642 3 Other Structural BMPs and ESD Strategies 10,143 $5.25 1,932 4 Priority Neighborhoods ESD Retrofits 383 $0.24 1,604 5 Riparian Reforestation 2,419 $2.25 1,077 6 Street Sweeping - $0.02 0 7 Stream Restoration - $27.72 0 8 Lawn Care Education - $0.01 0

The percent reduction in pollutants was computed using our WTM baseline load to track restoration efforts against the targeted stormwater WLA reduction for phosphorus (30%). From there, the iterative approach was used to track progress toward meeting the phosphorus WLA as shown in Table 30.

Table 30: Preliminary Results of WTM Modeling for Phosphorus

Phosphorus Cumulative Implementation Loading Cost Comments Phase % reduction Million $ from baseline WTM Baseline 0% Normalized to MDE Baseline Load $- WTM 2.0 7% High Priority and Other Potential Projects $2.78 WTM 3.0 11% ESD Strategies and Other Structural BMPs $3.68 WTM 3.0 17% Underperforming BMP Retrofits $6.15 WTM 3.0 17% Priority Neighborhoods ESD Retrofits $6.39 WTM 3.0 22% Riparian Buffer Reforestation $8.63 WTM 4.0 22% Street Sweeping $8.65 WTM 5.0 26% Lawn Care Education $8.66 WTM 5.0 27% Pet Waste Education $8.67 WTM 4.0 38% Stream Restoration $36.39 TMDL WLA 30.0% Waste Load Allocation

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The restoration strategy is further illustrated in Figure 57, where the implementation phases are shown in order with their resulting phosphorus load in comparison to the WLA. The cost for each implementation phase is also shown.

Figure 7: Phosphorus loading over restoration implementation phase

Based on the results of the modeling, lawn care and pet waste education, along with retrofits of underperforming BMPs were the most economically efficient practices for meeting the phosphorus load reduction requirements. From a cost perspective, structural stormwater practices are not the most cost effective strategies for meeting the TMDL requirement. Rather, the programmatic practices are more cost effective. However, the structural stormwater practices and stream restoration result in the greatest phosphorus reduction (Table 31).

Table 31: Individual restoration strategy cost effectiveness for phosphorus load reduction

Phosphorus Incremental Unit Cost Rank Restoration Strategy reduction Cost Lbs/year Million $ Lbs/Million $ 1 Lawn Care Education 51 $0.01 4,338.5 2 Pet Waste Education 26 $0.01 2,242.6 3 Retrofit of Underperforming BMPs 57 $0.90 63.2 4 Other Structural BMPs and ESD Strategies 176 $5.25 33.5 5 Riparian Reforestation 70 $2.25 31.2 6 Priority Neighborhoods ESD Retrofits 7 $0.24 27.5 7 Stream Restoration 150 $27.72 5.4 8 Street Sweeping - $0.02 0.0

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3.5 Trash Reduction and Nitrogen Load Tracking

Trash and non-TMDL pollutant reductions – nitrogen – were also tracked using the WTM. Outreach and Stewardship Strategy Education Project: Overall, trash and nitrogen were reduced by 31% To help watershed stakeholders and 68%, respectively. Reductions from baseline understand why street sweeping is condition are provided in Table 32. Specific increasing, stakeholder outreach such programmatic practices targeting trash load as installing educational signage on reduction can have a range of reduction roads is recommended. This can be accomplished through partnerships effectiveness between 5-30%, depending on the with organizations such as County-led intensity of implementation and frequency of Adopt-a-Road programs. Messaging follow-up. Examples include: anti-litter education should focus on the ways the campaigns, plastic bag bans, recycling programs, importance of keeping road debris out of the creeks as described in the adopt-a-road and adopt-a-stream, street sweeping, Practice Sheet entitled Education and enforcement. Outreach for Innovative Stormwater Management Outreach and Stewardship Campaign.

Table 32: Preliminary Trash and Nitrogen Results of WTM Modeling for Lower Monocacy watershed

% Reduction from Cumulative Cost Implementation Phase Baseline Load TN Trash Million $ WTM 1.0 – Baseline Load 0% 0% $0 WTM 2.0 – High Priority and Other Potential 9% 16% $2.78 Projects WTM 3.0 – Underperforming BMP Retrofits 14% 16% $3.68 WTM 3.0 – ESD Strategies and Other Structural 21% 27% $6.15 BMPs WTM 3.0 – Priority Neighborhoods ESD Retrofits 22% 28% $6.39 WTM 3.0 – Riparian Buffer Reforestation 25% 31% $8.63 WTM 4.0 – Street Sweeping 25% 31% $8.65 WTM 5.0 – Lawn Care Education 55% 31% $8.66 WTM 5.0 – Pet Waste Education 57% 31% $8.67 WTM 4.0 – Stream Restoration 68% 31% $36.39

Figure 8 illustrates the cumulative cost of implementation completed, current (FY2009-2016), and other potential BMPs to achieve trash and nitrogen load reductions in Lower Monocacy watershed.

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Figure 8: Trash and nitrogen load reduction over time and associated costs for Lower Monocacy watershed modeled using the WTM.

3.6 Impervious Cover Tracking

The Plan also considers the total impervious cover treated to the Maximum Extent Practicable (MEP) by the various strategies explored. Impervious cover treatment associated with full watershed restoration potential was analyzed by the County as follows: 1. All new structural BMPs installed after 2002 were considered MEP. 2. Retrofits of existing stormwater ponds installed prior to 2002, such that the impervious draining to the pond was not previously considered treated to the MEP, were credited as upgrades to the MEP. 3. Reforestation practices were given a ratio of 0.34 acres of impervious credit for every acre planted. 4. Stream restoration practices were given a ratio of 1 acre of impervious credit for every 100 linear feet restored. 5. Street sweeping practices were given a ratio of 0.4 acres of impervious credit for every ton of sediment collected.

Note that outreach and education efforts were not given any impervious cover credit. Table 33 below shows the breakdown of the impervious acres treated by BMP category and cost.

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Table 33: Impervious cover accounting for Lower Monocacy MS4 permit area

Impervious Cover Cumulative IC Cost Category Treated Treated acres acres Million $ WTM 1.0 - Existing BMPs, pre-permit 2010 21.8 0.0 $0 WTM 1.0 - Existing BMPs, post permit 2010 0.0 0.0 $0 WTM 2.0 - High Priority Pre-Assessment Sites 13.4 13.4 $2.63 WTM 2.0 - Other Potential Projects 0.8 14.1 $2.78 WTM 3.0 - Underperforming BMP Retrofits 8.2 22.4 $3.68 WTM 3.0 - Public ESD Retrofits 35.4 57.8 $6.15 WTM 3.0 - Private ESD Retrofits 2.3 60.1 $6.39 WTM 4.0 - Riparian Buffer Reforestation 23.1 83.2 $8.63 WTM 5.0 - Street Sweeping 2.8 86.0 $8.65 WTM 5.0 - Pet Waste, Lawn Care Education 0.0 86.0 $8.67 WTM 4.0 - Stream Restoration* 429.8 515.8 $36.39 Total Impervious Credit Available 515.8 acres Impervious Credit in Excess of Untreated Watershed Imperviousness -380.8 acres Total Impervious Credit for MS4 Permit Reporting 135.0 acres

Given the total watershed impervious acreage of 157 acres and a current impervious acreage treated to the MEP of 21.8 as shown in Table 33, there are 135 acres of potential impervious cover credit in the Lower Monocacy watershed. Figure 9 illustrates the accounting of impervious cover credit with the associated costs. Note that there are 381 additional impervious acre credits available in excess of the total untreated impervious in the watershed.

Figure 9: Impervious cover accounting per phase and associated costs for Lower Monocacy watershed.

October 2014 Page 38 of 42 Lower Monocacy Watershed Implementation Plan

4 Action Inventory Implementation Schedule

4.1 Lower Monocacy Watershed Implementation Schedule

The expected budgetary spending for the next Fiscal Years 2015-2019 is $1.39 Million, spent across the various implementation categories shown in Table 34.

Table 34: Budget for Lower Monocacy during the FY15-19 period

Budget Impervious Acres Categories Allocation Treated** (Million $) (acres)

Misc. Stream Valley Improvements $0.00 - Stormwater Management Retrofit - Government Facilities $0.01 <1 Stormwater Management Retrofit - Roads $0.16 3 Stormwater Management Retrofit - Schools $0.01 <1 Stormwater Management Retrofits- Countywide $1.21 6 Subtotal $1.39 9

Based on the total restoration potential analysis performed using the WTM, it will cost the County approximately $36.1 Million to meet the sediment TMDL requirements. At the current allocation of funds toward the Lower Monocacy watershed, and assuming a 5% growth rate, the County will meet the sediment TMDL by the 2035-2039 permit cycle.

Similarly for the phosphorus TMDL, it is anticipated that the County will meet the phosphorus TMDL by the 2035-2039 permit cycle.

The WTM modeling of the Lower Monocacy watershed showed that meeting the bacterial reduction required by the TMDL is not achievable by the restoration practices considered, and that the wildlife load within the watershed exceeds the technology available for removal. The complete suite of practices explored would cost $36.39 Million to implement, which would be exhausted by the 2035-2039 permit cycle.

Table 35 shows the County strategy for meeting the local TMDLs for the Lower Monocacy watershed.

October 2014 Page 39 of 42 Lower Monocacy Watershed Implementation Plan

Table 35: TMDL Reduction by Permit Cycles for the Lower Monocacy watershed

Impairment Units Target Percent Removal 2015-2019 2020-2024 2025-2029 2030-2034 2035-2039

Sediment tons/yr 60.8% 13.9% 19.9% 27.0% 33.8% 80.9%

Bacteria Billion MPN/yr 85.4% 21.7% 28.0% 34.8% 40.0% 43.0%

Nutrients (Phosphorus) lbs/yr 30.0% 9.1% 13.8% 19.2% 23.7% 37.5% Budget (Watershed Subtotal, $ M) $1.39 $1.78 $2.25 $2.89 $27.79 Note: County budgets presented do not include: completed, in design, and in construction projects; programmatic practices; private ESD; and RainScapes practices.

October 2014 Page 40 of 42 Lower Monocacy Watershed Implementation Plan

5 References

Army Corps of Engineers (USACE). 2008. Sligo Creek Study. Baltimore District. Baltimore, MD.

Baltimore Department of Public Works (BDPW). 2006. 2005 NPDES MS4 Stormwater Permit Annual Report. Submitted to Maryland Department of Environment. Water Management Administration. Baltimore, MD.

Caraco, D. 2009. New WTM – No Projections.xls, Personal Email Communication, October 14, 2009.

Caraco, D. 2001. The Watershed Treatment Model: Version 3.0. U.S. Environmental Protection Agency, Region V. Center for Watershed Protection. Ellicott City, MD

Center for Watershed Protection (CWP) and Chesapeake Stormwater Network (CSN). 2008. Technical Memorandum: The Runoff Reduction Method. Ellicott City, MD.

Center for Watershed Protection (CWP). 2007. National Pollutant Removal Performance Database Version 3.0. Center for Watershed Protection, Ellicott City, MD.

Chesapeake Bay Program (CBP) Nutrient Subcommittee. 2008. Infiltration and Filtration Practices: Definition and Nutrient and Sediment Reduction Effectiveness Estimates. Center for Watershed Protection, Ellicott City, MD.

Chesapeake Stormwater Network (CSN) and Biohabitats. 2011. Implementation Plan Guidance Document. Prepared for Montgomery County Department of Environmental Protection, Rockville, MD. http://www.montgomerycountymd.gov/dectmpl.asp?url=/Content/dep/water/esdStrategy.asp

Evans, B. M., S. A. Sheeder, and D. W. Lehning. 2003. A Spatial Technique for Estimating Streambank Erosion Based on Watershed Characteristics. Journal of Spatial Hydrology. Vol.3, No.1 Fall 2003

Frederick County Division of Public Works. 2004. Lower Monocacy River Watershed Restoration Action Strategy, Final Report. Frederick, MD.

Maryland Department of the Environment (MDE). 2012. Total Maximum Daily Load of Phosphorus in the Lower Monocacy River Watershed, Frederick, Carroll, and Montgomery Counties, Maryland. Baltimore, MD.

MDE. 2010a. Memorandum: 2010 Status of Approved Stormwater Wasteload Allocations for NPDES Regulated Stormwater Entities in Montgomery County. Baltimore, MD: Maryland Department of the Environment.

October 2014 Page 41 of 42 Lower Monocacy Watershed Implementation Plan

MDE. 2010b. Total Maximum Daily Loads of Trash for the Anacostia River Watershed, Montgomery and Prince George’s Counties, Maryland and the District of Columbia, Final. Baltimore, MD.

MDE. 2009. Technical Memorandum: 2009 Status of Approved Stormwater Wasteload Allocations for NPDES Regulated Stormwater Entities in Montgomery County. Baltimore, MD.

MDE. 2009. Total Maximum Daily Load of Fecal Bacteria in the Lower Monocacy River Watershed, Frederick, Carroll, and Montgomery Counties, Maryland. Baltimore, MD.

MDE. 2008. Total Maximum Daily Load of Sediment in the Lower Monocacy River Watershed, Frederick, Carroll, and Montgomery Counties, Maryland. Baltimore, MD.

Mukundan, R., D. E. Radcliffe, J. C. Ritchie, L. M. Risse and R. A. McKinley. 2010. Sediment Fingerprinting to Determine the Source of Suspended Sediment in a Southern Piedmont Stream. Journal of Environmental Quality 39:1328–1337. Mukundan, et al., 2010

Rosgen DL. 2006. Watershed assessment of river stability and sediment supply. Wildland Hydrology Books: Fort Collins, CO; 2–35.

Schueler, T. 1998. The performance of oil grit separators in removing pollutants at small sites. Technical Note 119. Watershed Protection Techniques. 2(4): 539-542. See also Technical Note 120.

October 2014 Page 42 of 42

Appendix A – List of High Priority Projects Lower Monocacy Watershed Implementation Plan

Lower Monocacy High Priority List

Watershed Project Type Project Name or Assessment ID Lower Monocacy Environmental Site Design (ESD) BCBC-RI-02 LBLB-RI-08 LBLB-RI-09 LBLB-RI-07 LBLB-RI-03 New Pond BCBC-RI-01

October 2014 Page A-2 Upland Assessment Map 1 Montgomery County Maryland

Lower Monocacy River March 2015

Legend

Streams

Concept Locations

Concept Neighborhoods

Concept New BMP

Assessed Locations

Assessed Neighborhoods

Assessed Reforestation

Assessed New BMP

Buildings

Roads

Forest

Non-MS4 Permit Area h c n a r Fahrney B 0 1,000 KEMPTOWN RD Feet

MOXLEY RD

CLARKSBURG RD Upland Assessment Map 2 Montgomery County Maryland

Lower Monocacy River March 2015

Legend

Streams

Concept Locations

Concept Neighborhoods

Concept New BMP

Assessed Locations

Assessed Neighborhoods

Assessed Reforestation

Assessed New BMP

Buildings

Roads

Forest

Non-MS4 Permit Area

0 1,000 Feet HAINES RD Upland Assessment Map 3 Montgomery County Maryland

Lower Monocacy River March 2015

Legend

Streams BCBC-RI-02 Concept Locations

CLARKSBURG RD Concept Neighborhoods MOXLEY RD

Concept New BMP

Assessed Locations

Assessed Neighborhoods

Assessed Reforestation

Be nne t t Cre BARNES RD Assessed New BMP ek

Buildings

Roads

Forest BETHESDA CHURCH RD Non-MS4 Permit Area

0 1,000 Feet HAINES RD

PURDUM RD PRICES DISTILLERY RD

HANEY AVE Upland Assessment

KEMPTOWN RD Map 4 Montgomery County Maryland

Lower Monocacy River March 2015

Legend

Streams

MOXLEY RD RIDGERD

Concept Locations CLARKSBURG RD Concept Neighborhoods

Concept New BMP

Assessed Locations Benn et t C re ek Assessed Neighborhoods

BELLISON RD Assessed Reforestation

Assessed New BMP

Buildings

Roads

Forest BETHESDA CHURCH RD

Non-MS4 Permit Area

0 1,000 Feet

HANEY AVE Upland Assessment Map 5 Montgomery County Maryland

Lower Monocacy River March 2015

Legend

Streams

Concept Locations

Concept Neighborhoods

Concept New BMP

Assessed Locations

Assessed Neighborhoods

Assessed Reforestation

Assessed New BMP OLD HUNDRED RD 270 PEACH TREE RD Buildings

Roads

Forest

Non-MS4 Permit Area

0 1,000 Feet

PEACH TREE RD

THURSTON RD Upland Assessment Map 6 Montgomery County Maryland

Lower Monocacy

HAINES RD River March 2015

Legend

AIKEN DR LEWISDALE RD Streams

Concept Locations LBLB-RI-05 Concept Neighborhoods LBLB-RI-06 RUDALE DR LBLB-RI-07 Concept New BMP

Assessed Locations h ranc k B PRESCOTT RD LBLB-RI-04 Dar Assessed Neighborhoods LBLB-RI-03 Assessed Reforestation

Assessed New BMP Lit tle B OLD HUNDRED RD enn ett C re Buildings FREDERICK RD e CROGHAN LA k

o Roads S p S270 X22 TO X18 HWY e r Br an

c

h Forest

HYATTSTOWN MILL RD Non-MS4 Permit Area

PRESCOTT RD

270 0 1,000 Feet

W PEACH TREE RD i l d

c

a

t

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r a n c h

CLARKSBURG RD Upland Assessment Map 7 Montgomery County Maryland

HANEY AVE Lower Monocacy

HAINES RD River March 2015

Legend

PURDUM RD Streams

CLARKSBURG RD LEWISDALE RD Concept Locations

Concept Neighborhoods RUDALE DR MOUNTAIN VIEW RD JOHNSON DR Concept New BMP PRICES DISTILLERY RD Assessed Locations

Assessed Neighborhoods

Assessed Reforestation

Assessed New BMP

Buildings

BURNT HILL RD Roads

Forest

Non-MS4 Permit Area eek tt Cr Benne le i tt L 0 1,000 LBLB-RI-02 Feet KINGS VALLEY RD Spring Garden Estates

KINGS VALLEY RD Upland Assessment Map 8

BETHESDA CHURCH RD Montgomery County Maryland

HANEY AVE Lower Monocacy BCBC-RI-01 River RIDGE RD March 2015

LEWIS DR Legend Ben ne tt C reek Streams

Concept Locations

Concept Neighborhoods

JOHNSON DR Concept New BMP MOUNTAIN VIEW RD Assessed Locations k ree C tt Assessed Neighborhoods ne Ben tle it L Assessed Reforestation

Assessed New BMP LBLB-RA-011

Buildings

Roads

Forest

Non-MS4 Permit Area

OAK DR

LBLB-RI-02 0 1,000 KINGS VALLEY RD Feet KINGSTEAD RD

Spring Garden Estates

KINGS VALLEY RD Upland Assessment Map 9 Montgomery County PEACH TREE RD Maryland THURSTON RD

Lower Monocacy River March 2015

Legend

Streams

Concept Locations

Concept Neighborhoods

Concept New BMP

Assessed Locations

Assessed Neighborhoods

Assessed Reforestation

Assessed New BMP

Buildings

Roads

Forest COMUS RD SUNRIDGE DR

PEACH TREE RD Non-MS4 Permit Area

SLIDELL RD 0 1,000 Feet Upland Assessment Map 10 Litt l PEACH TREE RD e W B Montgomery County i e l n tt d ne C Maryland c re a ek t B r a n c h Lower Monocacy S o p CLARKSBURG RD e River r S270 X22 TO X18 HWY B March 2015 r a n c h Legend

N270 X18 TO X22 HWY Streams

Concept Locations

Concept Neighborhoods

Concept New BMP 270 CAMPING RIDGE RD Assessed Locations

FREDERICK RD Assessed Neighborhoods

Assessed Reforestation

Assessed New BMP

LBLB-RA-012 Buildings

LBLB-RI-01 Roads

Forest

Non-MS4 Permit Area

SLIDELL RD COMUS RD 0 1,000 Feet Upland Assessment LBLB-RI-02 Map 11 Spring Montgomery County Garden Maryland Estates

Lower Monocacy

CLARKSBURG RD River L i ttl March 2015 e LBLB-RI-11 B KINGS VALLEY RD en n e t t Cree BURNT HILL RD k Legend LBLB-RA-010 Streams

KINGSLEY RD Concept Locations

Concept Neighborhoods

HAILEY DR Concept New BMP

Assessed Locations STRINGTOWN RD Assessed Neighborhoods

Assessed Reforestation

Assessed New BMP

Buildings

Roads

DANCREST DR Forest

Non-MS4 Permit Area

0 1,000 Feet Upland Assessment LBLB-RI-02 OAK DR Map 12 KINGSTEAD RD Montgomery County Maryland BELLEHAVEN BLV

Lower Monocacy River Spring March 2015 KINGS VALLEY RD Garden Estates Legend LBLB-RA-010 Streams

Concept Locations

Concept Neighborhoods

HAILEY DR Concept New BMP

Assessed Locations

RIDGE RD Assessed Neighborhoods

Assessed Reforestation

Assessed New BMP

Buildings

Roads

Forest

Non-MS4 Permit Area

0 1,000 Feet

Watershed Assessment: Lower Monocacy River New BMP Assessment

Damascus Volunteer Fire Dept. (BCBC-RI-001)

July 2014 1 New BMP Assessment Results New BMP Assessment Summary for BCBC-RI-001

Location: 10211 Lewis Dr., Damascus, Montgomery County, MD Subwatershed: Little Bennett Creek Watershed: Lower Monocacy River Property Ownership: Damascus Volunteer Fire Department (proposed New BMP located on American Legion Post 171 property, not the assessed VFD property) Assessment ID Description: BCBC-RI-001, Damascus Volunteer Fire Department Activity Center Assessment Date: 09-09-2013

Drainage Area: 2.3 acres, 1.50 acres Impervious (65%), Institutional land use Major Project Components: Filtering Practice Targeted Stormwater Criteria: Water Quality Targeted Filter Area1/Available Area: 680 square feet/750 square feet Targeted Water Quality Volume2/Provided Storage3: 5,300 cubic feet/5,300 cubic feet Impervious Cover Treated: 1.5 acres (65%) Pollutant Load Reduction: 15.5 lbs/yr TN, 2.3 lbs/yr TP, 0.67 tons/year TSS

Site Description: Approximately 1.5 acres of impervious surface including a large parking lot and roof areas drain to the rear of the Damascus VFD Activity Center. The drainage area includes a portion of the American Legion Post parking lot and driveway. A structural BMP placed behind the VFD lot in American Legion Post 171 property, such as a surface sand filter, could be employed to treat stormwater runoff leaving the site. Some trees and brush would need to be cleared to make way for the BMP. The sand filter would act to remove pollutants from stormwater that washes from the site during rain storms. The sand filter in this concept has a surface area of about 680 square feet.

Table 1: New BMP Assessment Results

Measure Results Impervious Cover Treated 1.50 ac Subwatershed Biological Condition Good Site Access No Constraints Utility Conflicts Electric Permitting Constraints None Land Use Conflicts None Property Ownership Volunteer Fire Department Planning Level Design & Construction Cost $98,500

1 Using sizing criteria from Maryland Department of the Environment 2000 Stormwater Design Manual 2 Assumes 1-inch rainfall event 3 Provided storage is the volume of runoff that the New BMP may be able to treat given existing site conditions

July 2014 2 New BMP Assessment Results

Figure 1: Damascus VFD Activity Center (back) facing north toward American Legion (beyond fence). This pavement would be directed to drain to the proposed sand filter BMP placed off the pavement to the left.

Figure 2: Example of BMP sand filter used to improve the quality of runoff from paved areas. The surface in this photo is gravel with the sand beneath, however grass or other vegetative cover may be appropriate depending on the final soil mix chosen for the filter.

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SENECA WATERSHED Û New BMP Contour 2ft NEW BMP ASSESSMENT: "/ Stormwater Inlet EXISTING CONDITIONS Drainage Area BCBC-RI-001 / DAMASCUS !. Stormwater Outlet Building JULY 2014 !@ Stormwater Manhole Parking Lot Stormwater Pipe Road Flow Line Property Boundary 4 76 6 6 7 [ 0 20 40

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MONOCACY WATERSHED Proposed NEW BMP ASSESSMENT: Features Existing Features CONCEPT DESIGN Surface Sand Contour 2ft Property Boundary BCBC-RI-001 / DAMASCUS Filter "/ Stormwater Inlet Sidewalk JULY 2014 Flow Line !. Stormwater Outlet Building Stormwater Pipe Parking Lot Drainage Area Road

Watershed Assessment: Lower Monocacy River New BMP Assessment

Bethesda United Methodist Church (BCBC-RI-002)

July 2014 1 New BMP Assessment Results New BMP Assessment Summary for BCBC-RI-002

Location: 11901 Bethesda Church Road, Damascus, Montgomery County, MD Subwatershed: Little Bennett Creek Watershed: Lower Monocacy River Property Ownership: Private Assessment ID Description: BCBC-RI-002, Bethesda United Methodist Church Assessment Date: 09-09-2013

Drainage Area: 1.39 acres, 0.49 acres Impervious (35%), Institutional land use Major Project Components: Bioretention Targeted Stormwater Criteria: Water Quality Targeted Filter Area1/Available Area: 1,488 square feet/5,700 square feet Targeted Water Quality Volume2/Provided Storage3: 1,860 cubic feet/1,860 cubic feet Impervious Cover Treated: 0.49 acres (100%) Pollutant Load Reduction: 9.0 lbs/yr TN, 1.0 lbs/yr TP, 0.26 tons/year TSS

Site Description: According to 2010 as-built documents, the recent additional parking and multi-purpose hall are being treated by multiple dry well facilities. However, the drainage areas do not include the church building nor a portion of the older parking lot. A micro-bioretention area placed at the front of the building, and a linear bioretention area along the corner of the parking area could be employed to treat stormwater runoff leaving the untreated portions of the site. Care should be taken to avoid underground septic system utilites, utility poles and overhead wires, and guy wires. Some shrubbery would need to be cleared to make way for the BMP, but the majority of the area is currently turf. The bioretention would act to remove pollutants from stormwater that washes from the site during rain storms. Flowering native herbaceous and shrub species could be a landscape amenity, as well as provide beneficial habitat for birds and pollinator species. The two bioretention areas in this concept have a combined surface area of about 1,488 square feet.

Table 1: New BMP Assessment Results

Measure Results Impervious Cover Treated 0.49 ac Subwatershed Biological Condition Good Site Access No Constraints Utility Conflicts Septic, Overhead Electric Permitting Constraints None Land Use Conflicts None Property Ownership Private, Church Planning Level Design & Construction Cost $115,500

1 Using sizing criteria from Maryland Department of the Environment 2000 Stormwater Design Manual 2 Assumes 1-inch rainfall event 3 Provided storage is the volume of runoff that the New BMP may be able to treat given existing site conditions

July 2014 2 New BMP Assessment Results

Figure 1: Existing pavement at the Bethesda United Methodist Church. This pavement would be directed to drain to the proposed bioretention BMP within the current turf area.

Figure 2: Example of bioretention BMP used to improve the quality of runoff from paved areas. Native plants as a vegetative cover and a porous soil landscaping bed are used to filter runoff and promote infiltration into the ground.

July 2014 3 616 [ 28008

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LOWER MONOCACY WATERSHED NEW BMP ASSESSMENT: Existing Features

EXISTING CONDITIONS Contour 2ft Property Boundary BCBC-RI-002 / BROWNINGSVILLE Drainage Area Sidewalk JULY 2014 Dry Well Building

Flow Line Parking Lot Road 616 [ 28008

620 0 40 80 Feet 12001

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LOWER MONOCACY WATERSHED Proposed Features Existing Features NEW BMP ASSESSMENT: CONCEPT DESIGN Bioretention Contour 2ft Property Boundary BCBC-RI-002 / UNITED METHODIST /" Stormwater Inlet Dry Well Sidewalk JULY 2014 .! Stormwater Outlet Flow Line Building Stormwater Pipe Parking Lot Drainage Area Road

Watershed Assessment: Lower Monocacy River New BMP Assessment

Hyattstown Christian Church (LBLB-RI-007)

July 2014 1 New BMP Assessment Results New BMP Assessment Summary for LBLB-RI-007

Location: 26012 Frederick Road, Clarksburg, Montgomery County, MD Subwatershed: Little Bennett Creek Watershed: Lower Monocacy River Property Ownership: Private Assessment ID Description: LBLB-RI-007, Hyattstown Christian Church Assessment Date: 09-06-2013

Drainage Area: 0.73 acres, 0.40 acres Impervious (55%), Institutional land use Major Project Components: Bioswale/Bioretention Targeted Stormwater Criteria: Water Quality Targeted Filter Area1/Available Area: 1,160 square feet/3,783 square feet Targeted Water Quality Volume2/Provided Storage3: 1,450 cubic feet/1,450 cubic feet Impervious Cover Treated: 0.40 acres (100%) Pollutant Load Reduction: 4.8 lbs/yr TN, 0.7 lbs/yr TP, 0.19 tons/year TSS

Site Description: The two parcels in Hyattstown (ACCT# 00031251 and 00022085) belong to the Hyattstown Christian Church which is proposed for retrofit. A linear bioswale feature and micro-bioretention area placed along the southeast perimeter of the site could be employed to treat stormwater runoff from the buildings and parking lots. The downspouts from the church should be disconnected and allowed to sheetflow to the BMPs. Care should be taken to avoid underground electric and sewer utilities, and utility poles. The site is carved into the side of a large hillslope, so a perimeter swale or berm along the northwest side of the rear parking area is recommended to divert off-site runon from entering the proposed BMP. A gravel verge at the edges of the parking lots would act to slow sheetflow down and distribute runoff into the facilities. Underdrains and overflow provisions could be discharged to existing drainage swales to the south and east along Frederick Road. Flowering native herbaceous and shrub species in the BMPs could be a landscape amenity, as well as provide beneficial habitat for birds and pollinator species. Table 1: New BMP Assessment Results

Measure Results Impervious Cover Treated 0.40 ac Subwatershed Biological Condition Good Site Access Shallow bedrock possible Utility Conflicts Sewer, Possible Electric Permitting Constraints None Land Use Conflicts None Property Ownership Private, Church Planning Level Design & Construction Cost $68,100

1 Using sizing criteria from Maryland Department of the Environment 2000 Stormwater Design Manual 2 Assumes 1-inch rainfall event 3 Provided storage is the volume of runoff that the New BMP may be able to treat given existing site conditions

July 2014 2 New BMP Assessment Results

Figure 1: Existing pavement at the Hyattstown Christian Church. This pavement would be directed to drain to the proposed bioretention BMP within the current turf area.

Figure 2: Example of bioretention BMP used to improve the quality of runoff from paved areas. Native plants as a vegetative cover and a porous soil landscaping bed are used to filter runoff and promote infiltration into the ground.

July 2014 3 2 0 5 0 0 2

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LOWER MONOCACY WATERSHED Û New BMP Contour 2ft NEW BMP ASSESSMENT: "/ Stormwater Inlet EXISTING CONDITIONS Drainage Area LBLB-RI-007 / HYATTSTOWN !. Stormwater Outlet Building JULY 2014 !@ Stormwater Manhole Parking Lot Stormwater Pipe Road Flow Line Property Boundary 26028

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LOWER MONOCACY WATERSHED Proposed Existing '' '' '''F'eatures Features NEW BMP ASSESSMENT: '' ''' ' '' ' Forebay Contour 2ft CONCEPT DESIGN ' '''''' LBLB-RI-007 / HYATTSTOWN Bioretention/Bioswale Property Boundary JULY 2014 /" Stormwater Inlet Sidewalk .! Stormwater Outlet Building Grass Swale Parking Lot Flow Line Road

Watershed Assessment: Lower Monocacy River New BMP Assessment

Middleboro Drive (LBLB-RI-008)

July 2014 1 New BMP Assessment Results New BMP Assessment Summary for LBLB-RI-008

Location: 10924 Middleboro Drive, Damascus, Montgomery County, MD Subwatershed: Little Bennett Creek Watershed: Lower Monocacy River Property Ownership: Public ROW Assessment ID Description: LBLB-RI-008, Middleboro Drive Assessment Date: 09-09-2013

Drainage Area: 2.9 acres, 0.70 acres Impervious (23%), residential land use Major Project Components: Bioswale Targeted Stormwater Criteria: Water Quality Targeted Filter Area1/Available Area: 2,139 square feet/5,565 square feet Targeted Water Quality Volume2/Provided Storage3: 2,674 cubic feet/2,674 cubic feet Impervious Cover Treated: 0.70 acres (100%) Pollutant Load Reduction: 18.4 lbs/yr TN, 1.7 lbs/yr TP, 0.41 tons/year TSS

Site Description: The neighborhood is situated on rolling topography with typically moderate (5%) front yard slopes. The neighborhood has open section roads that drain to grass swales and stormwater inlets in the right-of-way (ROW). Installation of linear bioswale features within the ROW is proposed to treat neighborhood runoff and reduce the stormwater impact to nearby surface water resources. There are no sidewalks, however, sewer and water utilities are concentrated in the ROW. Therefore, in the proposed concept design, a linear bioswale feature is proposed within the ROW swale opposite water utilities. Sewer pipes are generally deeper and can be avoided by a shallow bioswale installation. The majority of the neighborhood drains to a single 48-inch storm drain that dumps to the stream. The outfall is at the bottom of a deep ravine. If similar ROW retrofits were implemented throughout the neighborhood drainage area to the outfall, 8.55 acres of impervious could be treated at a total retrofit cost of $383,900. The option shown only includes a small drainage area to the last inlet of the system. Table 1: New BMP Assessment Results

Measure Results Impervious Cover Treated 0.70 ac Subwatershed Biological Condition Good Site Access Good Utility Conflicts Sewer, Water Permitting Constraints None Land Use Conflicts None Property Ownership Public ROW/HOA Planning Level Design & Construction Cost $52,600

1 Using sizing criteria from Maryland Department of the Environment 2000 Stormwater Design Manual 2 Assumes 1-inch rainfall event 3 Provided storage is the volume of runoff that the New BMP may be able to treat given existing site conditions

July 2014 2 New BMP Assessment Results

Figure 1: Stormwater manhole and easement which drains to an outfall in a deep ravine in the woods. The ROW swales drain to this outfall.

Figure 2: Example of bioretention BMP used to improve the quality of runoff from paved areas. Native plants as a vegetative cover and a porous soil landscaping bed are used to filter runoff and promote infiltration into the ground.

July 2014 3 A V O N [ LE A RID 7 R RAD E S 0 175 350 GE P 38 TOCK L T CT R S D S Feet K O A R C O E L P 58 P 88 7 A 6 KIN G 60 ST 6 7 BR EA 5 IX D 7 W RD OR TH CT

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6 5 2

Û

R D O R O B E 6 L 62 D D I 670 M 674

680 666

672 676

682 6 6 86 84 690 692 696

700 69 4 7 02 7 04 7 06 7 08

M 0 1 2 I 7 1 D 7 D CT L E RO B O O EB R DL O ID D M R

7 1 4

LOWER MONOCACY WATERSHED Û New BMP Contour 2ft NEW BMP ASSESSMENT: /" Stormwater Inlet EXISTING CONDITIONS Drainage Area LBLB-RI-008 / DAMASCUS .! Stormwater Outlet Building JULY 2014 !@ Stormwater Manhole Parking Lot Stormwater Pipe Road Flow Line Property Boundary 10904 10900 [ 10820 0 50 100 Feet 10932

654 10928 6 5 644 0 634 6 6 632 36 6 64 0 2 6 6 5 640 6 6 638 4 10940 0 63 10936 646

10924 6 5 2

R 10920 D O R O B E 66 L 2 D D I 670 M 10935 674

10939 10916 10925

68 10912 4 10943 10917

6 8 6 694 00001 00005 7 0 8 10908 10909

710 7 06 7 0 7 4 0 2 2 71 00009

7 00002 M 0 0 ID 6 6 9 T D 9 6 C L 2 10904 E RO B O O EB R DL 6 O ID 9 4 0 D M 71 R 00006 10900 10801 6 6 8 8 6 2 6 6 0 10829 7 6 7 6 6 10805 2 10832 LOWER MONOCACY WATERSHED Proposed Existing Features NEW BMP ASSESSMENT: Features CONCEPT DESIGN Bioswale Contour 2ft LBLB-RI-008 / DAMASCUS /" Stormwater Inlet Property Boundary JULY 2014 .! Stormwater Outlet Sidewalk Stormwater Pipe Building Flow Line Parking Lot Road