Forest Service AOP Policy and Program. John R. Kattell, P.E. Northern Region Structures Engineer

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1 Forest Service AOP Policy and Program John R. Kattell, P.E. Northern Region Structures Engineer

2 AOP Policy and Program In years past: Aquatic passage to be considered where important and economically feasible. Culverts designed for Q25. Thus we created many barriers. Typical Culvert AOP Barrier

3 AOP Policy and Program Within the last ten years More emphasis (importance) on Aquatic passage. (laws) T&E Species Act Clean Water Act road crossings shall not disrupt migration of aquatic life. National Forest Management Act habitate shall be managed to maintain viable populations preserve and enhance the diversity of plant and animal communities. No management practices shall cause blockages of water courses..

4 AOP Policy and Program Within the last ten years - continued Substantial increase: Aquatic species information. Culvert and Road Inventory information. Design concepts. Economic feasibility threshold has risen. Simple Culvert Less than $10,000 AOP crossing - $40,000 + Funding Programs specific to AOP. Current Highway Bill provides $10 mil for 6 years. Numerous partners willing to help fund projects. Our values and priorities have changed!

5 AOP Policy and Program Northern Region Guidance for Aquatic Species Passage Design (11/03/2003) The following alternatives for stream crossings should be considered in order of preference: 1. No Structure 2. Streambed simulation strategies 3. Hydraulic design a last resort.

6 Stream Simulation: If the channel inside a culvert or under a bridge, simulates the dimensions, character, and processes of the adjacent natural channel, it will present no more of an obstacle to movement of organisms than the natural channel.

7 AOP Policy and Program Aquatic Species Passage Design over the short and long term. Design must survive various flood events over time without creating future aquatic barriers. Stream Simulation gives best chance to meet these objectives.

8 Aquatic Passage Barrier Typical FS Culvert

9 Bridge Design with Stream Simulation Principals

10 Stream Simulation Design

11 Stream Simulation Design Interdisciplinary Design Team Biologist Construction Partner Hydrologist Project Leader Civil Eng. Geotech Structural Eng.

12 Objectives For Stream Simulation Design 1. Provide for the stream dimensions, character, and processes. Water, Wood, Sediment, and Species 2. Provide for road function Users, Safety, Drainage, Low Maintenance

13 Stream Simulation Design Interdisciplinary Design Stream function Biologist Hydrologist Road Function Civil Engineer Structural Engineer Geotechnical Construction

14 Interdisciplinary Design- Stream Function Primary disciplines Hydrologist Biologist Maybe a Geomorphologist

15 Interdisciplinary Design- Stream Function Large Scale Processes Floods Fire Mass Failures Debris Torrents Wind Throw Drought Organism Life Cycles Nutrient Cycling Cumulative Human Impacts What it Means to Crossing Design 1. Water Transport 2. Wood Transport 3. Sediment Transport 4. Species Passage

16 Interdisciplinary Design- Stream Function Base Flow Bankfull (normal high) Flow Water Transport Flood Flow

17 Interdisciplinary Design- Stream Function Wood Transport Stream Function energy dissipation, grade control Habitat Nutrient Cycling Structure Failure / Maintenance

18 Interdisciplinary Design- Stream Function Scour & Deposition Structure Failure / Maintenance Sediment Transport

19 Interdisciplinary Design- Stream Function Species Passage Consider all aquatic species, life stages and life forms.

20 Interdisciplinary Design- Stream Function From Rosgen 1994

21 Five Channel Forms of Montgomery & Buffington

22 Stream Function - Gradient Possible range of future profiles Incised channel may aggrade or be restored Road crossing Potential aggradation from slope failures Remove backwater deposition Alluvial scour depth of existing channel Debris jams are temporary Bedrock limits incision Replacement culvert enlarged, countersunk

23 Stream Function Substrate Considerations (Bed Design) -Mimic natural substrate -Maintain Velocities -Energy Dissipation -Hold Substrate

24 Interdisciplinary Design- Stream Function (Primarily Hydros and Bios) Evaluate Stream Characteristics Prioritize what s important Can Mother nature finish the job? Look at big picture Other mitigations Identify Stream Simulation design criteria Bankfull =..?? Pass?? yr flood event. Aquatic Species..?? Stream Type and/or Planform

25 Interdisciplinary Design- Road Function Primary Discipline Civil Engineer Users ADT Safety Maintenance Copper Creek Helena NF 8/30/05

26 Interdisciplinary Design- Road Function BMP s & Drainage Design Speed Design Vehicle Alignment Vertical Horizontal Structure Type Relief Creek NP

27 Interdisciplinary Design- Structures Primary Discipline Structural or Civil Engineer Geotechnical

28 Interdisciplinary Design- Structures Which Structure to Use? Must consider: Road Management objectives. Road alignments. Span. Depth to streambed. Scour potential Stream lateral stability. Debris. Stream Gradient. Must consider - continued: Construction Access. Material sources. Structure manufacturers. Costs. Construction Risks. Geotechnical. Foundations.

29 Interdisciplinary Design- Structures Basic Structure Types Bridge Box Pipe Arch Bottomless Arch Embedded Round

30 Structure - Culverts CMP Squash

31 Structure Structural Plate Bottomless Arch

32 Bottomless Concrete Box

33 Structure - Bridges Precast Concrete

34 Timber Slabs

35 Concrete Slab

36 Steel Stringer w/timber deck

37 What Structures work best where? When? From Rosgen 1994

38 Road alignment makes this a difficult site.

39 Road Function Interdisciplinary Design- Road Function Relief Creek NP Plan

40 Interdisciplinary Design- Road Function Relief Creek - NP

41 Stream Plan and Profile

42 Culvert and Stream Detail

43 Interdisciplinary Design- Construction

44 Interdisciplinary Design- Construction Importance of Construction! Not enough to just have good design. Work is new to contractors. Need good oversight / Inspectors.

45 AOP Summary Our Values have changed. Importance has increased Cost tolerance has increased Increased knowledge of species, inventory and design concepts. Funding has increased. Our interdiciplinary folks are learning. FS, A/E s, etc. We feel we are doing good work.