40
40
45
50
55
40
40
45
45
45
45
50
50
5050
50 50
55
5555
55
55
55
55
60
60
60
60
60
60
60
60
6060
65
65
65
65
65
65
65
65
65
65
70
70
70
70
70
70
75
75
75
75
758080
80
85
85
90
90
95
CO
LO
NIA
L N
ATIO
NA
L
HIS
TO
RIC
PA
RK
WA
Y
FLOW
FLOW
3+61.43
1+00
2+003+00
INTERSTATE 64WESTBOUND
3' MINIMUM
THE UNNAMED TRIBUTARY THAT FLOWS INTO QUEENS LAKE HAS EXPERIENCED SIGNIFICANTCHANNEL DEGRADATION AND EROSION, WHICH IS CONTRIBUTING TO LOCALIZEDSEDIMENTATION AND NUTRIENT CONTRIBUTIONS TO DOWNSTREAM RECEIVING WATERS. THISCONCEPTUAL RESTORATION DESIGN INCORPORATES A PERMANENT LONG-TERM SOLUTION,THAT WILL UTILIZE NATURAL CHANNEL DESIGN (NCD) PRINCIPLES, WHERE APPROPRIATE, ANDVEGETATION THAT IS NATIVE TO THE REGION.
THE PROPOSED DESIGN USES ROSGEN'S NCD METHODOLOGY (ROSGEN, 1996), MIMICKINGSLOPES AND BED FEATURES THAT ARE FOUND IN OTHER NATURAL STREAM CHANNELS WITHSIMILAR CHARACTERISTICS. BANKFULL CROSS-SECTIONAL AREAS OBSERVED IN THE FIELD,COUPLED WITH MODELED HYDROLOGY AND HYDRAULICS CALCULATIONS, WERE USED AS THEBASIS FOR CHANNEL SIZE. SLOPES IN THE SYSTEM ARE PROPOSED TO BE NORMALIZED THROUGHA SERIES OF ROCK GRADE CONTROL STRUCTURES THAT WILL SPREAD THE VERTICAL DROPTHROUGHOUT THE PROJECT, RATHER THAN IN ONE LOCATION (AT THE HEADCUT). THISRESTORATION WILL IMPROVE LOCAL HYDRAULICS AND REDUCE ENERGY AND BED EROSION. COBBLE WILL BE ADDED TO THE SYSTEM FOR VERTICAL SUPPORT AND HABITAT, AND SIDE SLOPESWILL BE GRADED GENTLY ENOUGH SO NATIVE VEGETATION CAN GROW AND FLOURISH. MATURE TREES WITHIN THE PROJECT AREA, INCLUDING THE APPROXIMATED ACCESS ROUTE(S),WILL BE AVOIDED TO THE GREATEST EXTENT PRACTICABLE, WHILE STILL ENSURING THE SUCCESSOF THE RESTORATION.
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5209 Center StreetWilliamsburg, Virginia 23188
INTERSTATE 64 & COLONIAL PARKWAY CONCEPTUAL RESTORATION PLANYORK COUNTY, VIRGINIA
PROPOSED CHANNEL CONDITION WITHINSTREAM STRUCTURES.
SECTION A-A'
WATER SURFACEELEVATION
BANKFULLWIDTH
STREA
M FLOW
A
A'
FOOTER ROCKS
NO GAPSBETWEEN ROCKS
HEADER ROCKS
HEADER ROCKS
FOOTERROCKS
SPLASH ROCKS
SPLASHROCKS
BED MIX
STREAM FLOW
BKF
BL
OUTERBANK
INNERBANK
SCOUR POOL
NTSDETAIL: TYPICAL J-HOOK WITH SILL
POOL
PLAN VIEW SECTION VIEWDETAIL: DOUBLE ROCK STEP (CONSTRUCTION DETAIL)
1' ±
1"=30'0 30' 60'15'
ILLUSTRATIVE LONGITUDINAL PROFILE - REACH 1VERTICAL SCALE: 1" = 5' HORIZONTAL SCALE: 1" = 20'
DISTANCE (FT.)
ELEVA
TION
(FT.)
30
35
40
45
55
50
60
6080100120160 140180200260 220240300 280320340360
EXISTING CHANNEL CONDITION WITHEROSION AND HEADCUT.
PROPOSED DOUBLE ROCK STEP
PROPOSED SINGLE ROCK STEP
PROPOSED J-HOOK WITH SILL
N
EXISTING VDOT LIMITED ACCESS LINE
4" - 6" COBBLE REINFORCEDBED MIX (12" DEEP)
COMPACTEDFILL
DOUBLE ROCK STEP
SINGLE ROCK STEP
EXISTINGGRADE
PROPOSEDGRADE
J-HOOK VANE WITH SILL
CLASS I RIP RAP
EXISTINGRIGHT-OF-WAY
EXISTINGRIGHT-OF-WAY
PROJECT NARRATIVE:
DETAILS
POTENTIAL RESTORATION PALETTE
RED MAPLE(ACER RUBRUM)
FLOWERING DOGWOOD(CORNUS FLORIDA)
WAX MYRTLE(MYRICA)
AMERICAN SYCAMORE(PLANTANUS OCCIDENTALIS)
SILKY DOGWOOD(CORNUS AMOMUM)
BLACK WILLOW(SALIX NIGRA)
NORTHERN RED OAK(QUERCUS RUBRA)
TULIP TREE(LIRIODENDRON)
AMERICAN HOLLY(ILEX OPACA)
AMERICAN HORNBEAM(CARPINUS CAROLINANA)
STEP ROCK: UPPER &LOWER DROP BOULDER
APPROXIMATEBANKFULL
SPLASH BOULDER/FOOTER
COMPACTED CLAYSTEP ROCK: UPPER& LOWER DROPBOULDER
SPLASH BOULDERFOOTER ROCK
EXISTING CULVERTOUTFALL 44.0 ±
EXISTING CULVERTOUTFALL 39.5 ±
EXISTING CULVERTOUTFALL 39.5±
EXISTING CULVERTOUTFALL 44.0±
PS1
STREAMFLO
W
APPROXIMATE LIMITS OF ACCESS(MATURE TREES TO BE AVOIDEDWHERE POSSIBLE)
PROPOSED LIMITS OFRESTORATION
ILLUSTRATIVE SECTION
PROPOSED BANKGRADE
CURRENT CHANNELCONDITION
REPLANTED VEGETATION(AFTER CONSTRUCTION)
COBBLESUBSTRATE
PROPOSEDCOMPACTED FILL
EXISTING VEGETATION(TO REMAIN)
EXISTING SOIL
NTS
ADDITIONAL ROCKSTEP STABILIZATION
PROPOSED ADJACENTSTORMWATER BASIN
VICINITY MAP
1"=1000'0 1000' 2000'500'
FUTURE STORMWATERBASIN BY OTHERS
N
PS1
PROJECT LOCATION
