Steep Gradient Fish Passage Culvert Alternatives to Bridges

Parameters

• Steep Gradient = Streams > 8% Slope• Permanent/Long Term Use Road

Typical Stream Characteristics

• Stream Gradient 8% - 14%• Headwater streams• Average Drainage Area 400 Acres• Large Cobble to Boulders• Not Bedrock• Fish Habitat Limited in Both Quantity and

Quality

Alternatives

• Bridges– Cost– Logistics

• Poor Alignment• Steep Gradient Roads

Alternatives

• Open Bottom Arch Pipe– Need Bedrock to Prevent Scour

Alternatives

• Weir/Baffle Culverts– ODFW & ODF

• Maintenance over time– Pool at the Outfall– Baffles inside the culvert

Adaptive Trial• Field Tour in the Fall

of 98’ With ODF & ODFW

• Stream Gradient Limits

• Concerns About Rock Remaining in Streambed Simulation Culverts

• Adaptive Trial

Adaptive Trial• Rock Retaining

Structure– Angle Iron Rack

• 3” x 3” x ¼” Internal/Outlet• 4” x 4” x ¼” Inlet• 5’ Spacing Between 1st

Two Rungs• 10’ Spacing Between

Remaining Rungs• 12” From Bottom of Pipe

Adaptive Trial• Rock Retaining

Structure– Rock Placement

• Bury 2’ to 3’ Boulders in Front of Outlet

• Place a Row of Boulders 15” or Larger Along Each Rung (Preferably 18” to 24”)

• Place Rock of Mixed Sizes to Fill in Between Rungs

Plan/Design

• Stream Profile– Stream Gradient– Depth of Fill– Ave Stream Width– Benchmark

Plan/Design

• Design– Pipe Size (Diameter/Length)– Placement– Gradient of Pipe– New Road Grade Elevation

Costs General

• Typical Costs range between $15,000 to $20,000– Factors:

• Stream Size• Fill Depth• Distance to Rock Source• Price of Steel

C R O S S I N G D A T E

S T R E A M G R A D I E N

T %

C U L V E R T G R A D I E N T

%

A P P R O X U P S T R E A M H A B I T A T ( f t )

S T R E A M W I D T H ( f t )

D R A I N A GE A R E A (a c r e s ) Q 5 0 c f s

C U L V E R T S I Z E

F in n C r k 1 0 1 0 1 9 9 9 1 1 .0 0 % 9 .0 0 % 8 0 0 7 2 9 0 8 3 1 1 2 " x 7 5 " x 4 6 '

C a la p o o y a 3 4 0 0 1 9 9 9 9 .5 0 % 8 .0 0 % 3 0 0 0 1 0 5 5 6 1 7 7 1 3 7 " x 8 7 " x 5 6 '

M o h a w k M a in l in e 2 0 0 0 9 .0 0 % 8 .0 0 % 1 6 0 0 1 1 6 2 0 1 7 4 1 4 2 " x 9 1 " x 8 4 '

M o h a w k 2 1 0 5 2 0 0 0 1 1 .0 0 % 9 .0 0 % 6 0 0 8 3 1 0 8 7 1 1 7 " x 7 9 " x 4 6 '

F in n C r k # 1 2 0 0 0 8 .0 0 % 7 .5 0 % 2 0 0 0 1 0 5 6 0 1 6 2 1 3 7 " x 8 7 " x 1 0 0 '

F in n C r k # 2 2 0 0 0 1 0 .5 0 % 1 0 .0 0 % 6 0 0 0 1 3 8 4 5 2 4 4 1 7 1 " x 1 1 0 " x 5 6 '

W e n d lin g 5 1 0 2 0 0 1 1 3 .0 0 % 1 1 .0 0 % 1 4 0 0 5 2 0 7 5 2 8 7 " x 6 3 " x 4 0 '

B u c k e y e C r ( C a l 3 5 0 0 ) 2 0 0 1 9 .5 0 % 8 .0 0 % 1 3 0 0 7 3 8 3 1 2 0 1 1 7 " x 7 9 " x 4 6 '

B u c k e y e C r k ( C a l M /L ) 2 0 0 2 9 .5 0 % 8 .0 0 % 2 4 0 0 1 0 4 0 5 1 2 7 1 2 8 " x 8 3 " x 7 0 '

G a te C rk 1 1 3 2 0 0 2 1 1 .5 0 % 1 0 .0 0 % 1 0 0 0 1 1 4 2 2 1 2 1 1 3 7 " x 8 7 " x 5 6 '

W e n d lin g 5 0 1 0 2 0 0 2 9 .5 0 % 8 .0 0 % 1 8 0 0 4 2 3 0 6 6 9 5 " x 6 7 " x 5 0 '

D o l la r 3 0 0 R d 2 0 0 3 1 0 .0 0 % 8 .5 0 % 1 5 0 0 6 1 4 0 3 7 8 7 " x 6 3 " x 4 2 '

T r o u t C r k 5 8 0 0 2 0 0 4 1 0 .5 0 % 9 .5 0 % 1 5 0 0 8 3 1 2 8 8 1 1 2 " x 7 5 " x 7 2 '

W h is k e y C r k 2 0 0 4 1 1 .0 0 % 9 .5 0 % 2 2 0 0 5 2 3 0 5 8 9 5 " x 6 7 " x 5 6 '

C a la p o o y a M /L ( b e lo w N . F o rk ) 2 0 0 4 9 .0 0 % 8 .0 0 % 2 7 0 0 9 4 7 0 1 9 0 1 2 8 " x 8 3 " x 5 0 'B o o th K e l ly M /L R ic h ie C k . 2 0 0 5 1 4 .0 0 % 1 2 .5 0 % 1 4 0 0 8 4 4 0 1 2 4 1 1 7 " x 7 9 " x 8 4 '

C a r tw r ig h t C k . 2 0 0 5 9 .0 0 % 8 .0 0 % 2 0 0 0 8 .5 5 3 0 1 3 3 1 1 7 " x 7 9 " x 5 0 'C a la p o o ia T r ib . 3 0 3 0 R o a d 2 0 0 5 1 2 .5 0 % 1 2 .5 0 % 1 3 0 0 8 3 5 5 1 1 1 1 1 2 " x 7 5 " x 7 4 'C a la p o o ia T r ib . 1 0 0 R o a d 2 0 0 6 1 0 .5 0 % 1 0 .0 0 % 3 0 0 0 5 2 1 5 6 0 9 5 " x 6 7 " x 5 6 'C a s h C k . D o l la r 6 0 0 2 0 0 6 1 1 .5 0 % 1 0 .0 0 % 3 3 0 0 8 4 1 0 1 1 0 1 1 2 " x 7 5 " x 5 6 '

1 0 .5 0 % 9 .2 5 % 2 0 4 0 8 3 9 7 1 1 6

S U M M A R Y O F S T E E P G R A D I E N T A D A P T I V E T R I A L S

A V G o f C R O S S IN G S