Anacostia River Watershed Restoration Plan Pope Branch Subwatershed Provisional Restoration Project Inventory August 2009 I. Background Located in southeast Washington, DC, Pope Branch is a first order tributary to the Anacostia River, approximately 1.6 miles in length. The entire stream lies within the Washington, DC city boundary, originating downstream of Fort Davis Drive SE and flowing in a northwesterly direction towards the Anacostia River. A portion of the stream, approximately 1,700 feet, is piped from the CSX railroad to an outfall at its confluence with the Anacostia River (COG, 2003). The Pope Branch subwatershed encompasses an approximately 248.5-acre area and is roughly bounded by Alabama Avenue SE to the east, Pennsylvania Avenue SE to the south, and Massachusetts Avenue SE to the north. The Pope Branch subwatershed is heavily urbanized. As a result, stormwater runoff from moderate storm events cause flashy and intense stream channel flows. The hydrologic alterations caused by urbanization and development have deteriorated the water quality of Pope Branch and degraded its natural habitat. In addition, watershed analyses have revealed that erosion of its stream banks during storm events is the primary cause of sedimentation within the Pope Branch subwatershed. There are several other current threats to both water quality and the health of the riparian buffer in the Pope Branch watershed. These include nonpoint source water pollution from stormwater runoff, a failing sewer line that traverses segments of Pope Branch, and lack of riparian cover along portions of the stream. As a result of this, Pope Branch does not support swimmable or secondary contact recreation uses. The potential for sewage line leaks into Pope Branch has produced a human health risk as well. In addition to the degraded water quality, the lower part of Pope Branch is piped, serving as a barrier to fish passage upstream and preventing potential recreational and aesthetic enjoyment of the riparian habitat. Recognizing both the severity and extent of environmental and ecological problems affecting the Anacostia River watershed and the need to better coordinate restoration efforts and resources, the three jurisdictions and the Metropolitan Washington Council of Governments entered into a Federal cost-sharing agreement with the U.S. Army Corps of Engineers to prepare a 10-year watershed restoration plan. The Anacostia River Watershed Restoration Plan will identify opportunities and approaches for restoring and protecting the 14 major subwatersheds and the tidal river reach within the Anacostia River basin. 1 Northwest Paint )"108 Branch Branch Little Paint Branch )"97 "198 Prince )"28 ) )"650 George's )"198 County )"182 Lower Indian G SE ut29 Creek E S t s 295 1 ÆÄ 3 Upper Beaverdam E K SE Creek 30th SE S n w la ir ¨¦§95 a F M Montgomery SE )"197 M S E Loud SE County )"895 M S E M SE 295 B r )" E 97 a S )" n c d h r 3 S M 201 N SE 3 N SE a " E s ¨¦§495 ) sa ch us P ett ope Nash SE s S Nash SE Bra E )"516 P nch o pe S O SE E )"320 )"193 Nash SE 787 )" 3 N 5 ash t T h SE e S x H E a 195 i s " g 3 Pope ) h SE 4 S Still Creek w t h E o E o S S d E h t S 8 E )"212 Middle 3 Brier Ditch District of "410 E ) E S S h s 8t i 3 v )"501 a Columbia D t r o F E 450 S )" a Upper m )"208 a b "202 a Hickey Run ) l Lower A ut29 Beaverdam )"295 ut50 Creek )"704 ut50 395¨¦§ )"214 )"332 ± Watts Branch ¨¦§295 Pope Fort Dupont Tributary ± 0123 Miles Branch Pope Branch Figure 1- Pope Branch Subwatershed Figure 2- Pope Branch Subwatershed Unit II. Restoration Inventory The following sections include stormwater retrofit, stream restoration, wetland restoration, fish blockage removal, riparian restoration, invasive plant management, and wildlife habitat improvement projects, land acquisition and other-related projects and actions for further evaluation by others. As previously noted, the restoration projects presented herein are conceptual or planning level only. It is recognized that more detailed drainage and site analyses are required, and that facility size and costs shown represent approximations. To facilitate reader understanding of the Pope Branch Subwatershed: Provisional Restoration Project Inventory, information has been organized into the following four sections: Section A - Impervious Features Summary Section B - Existing Stormwater Management Facilities Summary Section C - Candidate Restoration Project Summary Section D - Pope Branch Candidate Restoration Projects 2 A. Impervious Features Summary 3 Figure 3 - Summary: Pope Branch Impervious Features G y e l y t a t n s B a 1 s 3 s i 295 o ÆÄ r C e K l n d n w 30th la a ir R a F ta so ne in Ly Lura M nd y M al M e Lower Loud M M d N stia r h e h o 3 t ls c a c o 3 0 n An n 3 a r h t h B t N 4 N M 4 3 as t 3 s P h a t s op ch 7 1 e us 3 3 B e Nash ra Nash tts nc P h op e O Hi ghw oo d Nash T Na e sh x 3 a 5 3 s t 4 h Pope t h pe Po is er v rpent h a Middle Ca t D 8 t 3 r o High F wood th 38 a Upper m a b la A Legend Streams Subcatchment Subwatershed Unit Waterbody Buildings ± Roads, Parking Lot, and Sidewalks 0500 1,000 2,000 Feet 4 Table 1. Pope Branch: Summary - Impervious Surfaces Category Acres Miles 1. Roads 44.9 8.5 a. State/Fed 0.0 0.1 b. Local 44.9 8.4 2. Parking Lots 0.6 a. Public/Institutional 0.0 b. Private 0.6 3.Roofs 25.8 a. Public/Institutional 0.0 b .Private 2.1 c. Single Family 23.7 3. Other 16.4 a. Sidewalks * 4.1 b. Single Family Driveways ^ 12.3 Total 87.7 Avg. % Imperviousness 33.5% # of Single Family Homes 882 Total Drainage area 262 ^ Driveways assumptions Average Driveway=0.014 Acres Width equal to four feet, with a sidewalk running the * Sidewalks assumptions length of one side of the road. Note: Drainage area and tributary area calculated using the USGS 30-meter digital elevation model (DEM) 5 B. Existing Stormwater Management Facilities Summary 6 Figure 4 - Summary: Pope Branch Existing Stormwater Management BMP Sites ! ! ! G !! y e l y t t a n s B a 1 Lower s 3 s i 295 o ÆÄ r Area: 77 ac C 30th K # of BMPs: 2 n w la ir a F ! ta so ! ne L in yn M da Luray M le M Loud M M N tia h d c h e s o r t l c s a n o 3 0 n n A a 3 r 3 h h t t B 4 4 3 N N 3 h t t s 7 3 1 3 Nash Nash Ma P ss op ac e O hu H se ig Po tts hw pe oo B d ran Nash ch T N as e h x 3 a 5 3 s t 4 h Po t pe h pe Po is v h a t r D ente 8 Carp t Middle 3 r o Hig F hwoo Area: 85 ac d th # of BMPs: 0 38 a m a b la A Upper Area: 112 ac # of BMPs: 0 Legend Subwatershed Unit ! Existing Stormwater BMP Stormwater Controlled Drainage Area ± Subcatchment 0500 1,000 2,000 3,000 Feet 7 Table 2. Pope Branch: Summary – Pope Branch Existing Stormwater Management BMPs No. of Percent of D.A. Controlled Type Facilities Total BMP's (ac.) 1. Dry Pond 2. ED Dry Pond 3. Wet Pond 4. ED Wet Pond 5. Wetland (non-ED and ED) 6. Infiltration (Trench or Basin) 7. Oil Grit Separator Water Quality Inlet (e.g. 8. Stormreceptor, Bay Saver, etc) Bioretention /Rain Garden 9. 2 100.0% 0.4 10. 'Green Street'* 11. Bioswale 12. Grass Swale w/ Check Dams 13. Porous Pavement 14. Sand Filter 15. Underground Pipe Storage 16. Cistern 17. Green Roof 18. Other Total 2 100.0% 0.4 May include a mix of LID techniques including, but not limited to: bioretention, * rain garden, bioswale, soil amendment, etc. 8 C. Candidate Restoration Project Summary 9 Table 3. Summary: Restoration Candidate Projects Impervious Number Estimated Acreage Length Acreage Candidate Project Type of Cost ($) Controlled (feet) (ac) Projects (ac) 1 Stormwater Retrofit 13 3,992,000 58.6 - 128.9 2 Stream Restoration 3 2,570,000 - 8,800 - 3 Wetland Creation/Restoration 1 50,000 - - 1 Fish Blockage 4 3 820,000 - 4350 - Removal/Modification Riparian Reforestation, 5 Meadow Creation, Street Tree 2 28,500 - - 5.7 and Invasive Management 6 Trash Reduction 2 5,800 - 528 - 7 Toxic Remediation - - - - - 8 Parkland Acquisition 2 201,000 2.0 Total 26 7,667,300 58.6 13,678 138 10 Table 4. Pope Branch Subwatershed: Provisional Restoration Project Inventory ‘Unit Costs’* No. Practice Approx. Unit Cost ($) Stormwater Retrofit Existing Stormwater Management 1 ~ $1,000-3,000/acre of drainage Pond/Wetland Retrofitting New Stormwater Management 2 ~$3,000-5,000/acre of drainage Pond/Wetland Construction LID-Bioretention (w/Underdrain 3 ~ $100,000/ impervious acre System) 4 LID-Curbside/Street Planter ~ $100,000/ impervious acre 5 LID-Tree Box Filter ~ $54,450 - $65,340/impervious acre 6 LID-Green Roof ~ $42/square foot LID-Single Family Home Rain 7 ~ $5,000 per individual garden Garden LID-Single Family Home Rain 8 ~ $200/barrel (Typically, two per house) Barrel 9 Sand Filter ~ $20,000 to $25,000 per impervious acre** 10 Underground Pipe Storage ~ $15,000 per impervious acre*** 11 Permeable Pavement ~ $4.00 per square foot 12 LID Bioswale ~ $100,000/impervious acre 13 Storm Filter ~ $80,000/acre Stream Restoration/Fish Passage/Wetland Creation 14 Stream Restoration ~ $300/LF 15 Concrete Stream Channel Removal ~ $1,000/LF 16 Stream ‘Day Lighting’ ~ $2,000/LF Regenerative Stormwater 17 ~ $370/ft Conveyance System Fish Passage/Riffle Grade Control 18 ~ $150,000 per one foot barrier height Structure 19 Wetland Creation ~50,000/Acre Riparian Reforestation/Meadow Creation/ Invasive Plant Management 20 Riparian Reforestation ~ $9,000/acre 21 Wildflower Meadow Creation ~ $5,000/acre 22 Invasive Plant Management ~ $5,000/acre Trash Reduction/Water Quality 23 Manual Trash Pickup ~ $300/100 LF 24 Fresh Creek Trash Netting System ~ $1,000/acre of drainage 25 Signage ~ $1600 26 End–of-Pipe Trash Catching System ~ $4,000/ acre of drainage 27 Street Sweeping**** ~ $50/curb mile/year 28 Storm Drain Trash Grate ~ $500/inlet Land Acquisition 29 Land Acquisition ~ $100,000/acre includes (where appropriate) design and construction/installation costs ** escalated to 2009 dollars from “Schueler, T.R.
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