Route Comparison

Route A is shorter and ~$3,600 cheaper but crosses a seasonal creek. Route B avoids the creek for a modest premium.

Route A
$65,634
$93.76 / LF
700 LF · Direct alignment
Crosses seasonal creek
285' + 113' + 303' (measured)
0.32 acre disturbance · 399 tons aggregate
Route B
$69,273
$81.50 / LF
~850 LF · Southern alignment
Avoids creek entirely
Length estimated, pending survey
0.39 acre disturbance · 484 tons aggregate
CategoryRoute ARoute BDifference
General Conditions$10,500$9,500−$1,000
Clearing & Grubbing$3,322$4,047+$725
Earthwork$5,616$6,796+$1,180
Drainage (standard)$9,880$12,570+$2,690
Creek Crossing$4,590−$4,590
Base Course$13,819$16,776+$2,957
Surface Course$4,796$5,808+$1,012
Finish Work$4,550$4,740+$190
Direct Cost$57,073$60,237+$3,164
Contingency (15%)$8,561$9,036+$475
Estimated Total$65,634$69,273+$3,639
Route B costs ~$3,600 more overall but eliminates $4,590 in creek crossing work and all associated regulatory risk. The extra 150 feet of road adds ~$8,000 in material and labor, offset by avoiding the creek.

Risk Comparison

Route A carries significant unknowns around the seasonal creek. Route B has a more predictable cost profile.

Risk FactorRoute ARoute B
Fish presence If fish-bearing, ODFW requires fish passage. Could add $8,000–$25,000 for bottomless arch or bridge. N/A
Jurisdictional waters May trigger Section 404 (Army Corps) and/or DSL fill-removal permit. N/A
In-water work window Creek work limited to July 1 – Sept 15. Scheduling constraint. No constraint
Flow uncertainty 24" culvert assumed. If drainage area is larger, 36"+ required (+$1,500–$3,000). N/A
Permitting complexity Higher — potential ODFW, Army Corps, DSL involvement Standard approach permit only
Alignment certainty Measured (285' + 113' + 303') Estimated ~850 ft, needs survey
Long-term maintenance Creek culvert needs periodic inspection & debris clearing Standard road maintenance only
Route A worst case: If the seasonal creek is fish-bearing or jurisdictional, Route A costs could increase by $10,000–$25,000 for fish passage design, permitting, and a larger crossing structure — plus 2–4 months of permitting lead time. This would make Route A significantly more expensive than Route B.
The creek assessment is the decision point. If the creek is non-fish-bearing and non-jurisdictional, Route A is ~$3,600 cheaper and 150 ft shorter. If there's any question about fish or jurisdictional status, Route B eliminates that risk entirely for a modest premium.

Cost Breakdown

Base & Surface
33% $18,615
Drainage + Creek
25% $14,470
General Cond.
18% $10,500
Earthwork
10% $5,616
Finish Work
8% $4,550
Clearing
6% $3,322
Direct Cost
$57,073
+
Contingency (15%)
$8,561
=
Route A Total
$65,634

Line Items

1.0 General Conditions $10,500
ItemUnitQtyUnit PriceTotal
1.1 Mobilization / DemobilizationLS1$2,000$2,000
1.2 Surveying & StakingLS1$2,500$2,500
1.3 Erosion Control (Temporary)LS1$3,500$3,500
1.4 Traffic Control (approach work)LS1$500$500
1.5 Permits & FeesLS1$2,000$2,000
Subtotal 1.0$10,500
Erosion control increased ($3,000 → $3,500) for creek protection: additional silt fence, turbidity curtain, and stream buffer BMPs. Permits increased ($1,500 → $2,000) to cover potential ODFW fish screening and Lane County drainage review for the creek crossing.
2.0 Clearing & Grubbing $3,322
ItemUnitQtyUnit PriceTotal
2.1 Clear & grub (light woods)ACRE0.32$6,500$2,080
2.2 Strip topsoil (6")CY207$6.00$1,242
Subtotal 2.0$3,322
All cut trees and underbrush piled on-site per owner direction. Piling is included in the clearing unit price. No off-site hauling, chipping, or burning. Owner assumes responsibility for eventual disposal of piled material. No timber salvage credit.
3.0 Earthwork $5,616
ItemUnitQtyUnit PriceTotal
3.1 Excavation (common)CY100$12.00$1,200
3.2 Fill placement & compactionCY50$9.00$450
3.3 Subgrade preparationSY933$3.50$3,266
3.4 Proof-rollLF700$1.00$700
Subtotal 3.0$5,616
Minimal earthwork — undulating terrain with slight rise. Subgrade prep includes 3–4% crown, moisture conditioning, compaction. Proof-roll with loaded dump truck to identify soft spots; over-excavation at $15/CY additional.
4.0 Drainage $9,880
ItemUnitQtyUnit PriceTotal
4.1 18" CMP cross-drain culvertsLF72$40.00$2,880
4.2 Culvert end sections (metal)EA6$275.00$1,650
4.3 Ditch excavation (V-ditch, uphill)LF700$5.50$3,850
4.4 Rock check damsEA4$275.00$1,100
4.5 Rip-rap (outlet protection)CY5$80.00$400
Subtotal 4.0$9,880
Three standard cross-drain culverts at low points, each 24 LF. Ditch on uphill side only.
4A Creek Crossing $4,590
ItemUnitQtyUnit PriceTotal
4A.1 24" CMP culvert (F&I)LF30$55.00$1,650
4A.2 Concrete headwallsEA2$400.00$800
4A.3 Rip-rap — energy dissipationCY8$80.00$640
4A.4 Streambank stabilizationLS1$1,500$1,500
Subtotal 4A.0$4,590
This is the most uncertain cost in Route A. 24" CMP minimum; 36" may be required depending on drainage area (+$1,500–$2,000). If fish-bearing: ODFW requires width ≥ 1.2× bankfull, 20% embedment — could need bottomless arch or bridge, adding $8,000–$25,000. In-water work window: July 1 – Sept 15.
5.0 Base Course $13,819
ItemUnitQtyUnit PriceTotal
5.1 Geotextile separation (non-woven)SY1,244$2.25$2,799
5.2 Aggregate base — delivered (3/4" minus)TON290$32.00$9,280
5.3 Aggregate base — place & compactTON290$6.00$1,740
Subtotal 5.0$13,819
8" aggregate base in two 4" lifts. If borings show CBR > 5, base could reduce to 6" (saving ~$2,500). ~10 mile haul from Cottage Grove area quarry.
6.0 Surface Course $4,796
ItemUnitQtyUnit PriceTotal
6.1 Surface aggregate — delivered (3/4" minus)TON109$38.00$4,142
6.2 Surface aggregate — place & compactTON109$6.00$654
Subtotal 6.0$4,796
3" surface course of well-graded 3/4" minus crushed rock. Higher unit price than base due to tighter gradation spec.
7.0 Finish Work $4,550
ItemUnitQtyUnit PriceTotal
7.1 Shoulder gradingLF1,400$1.50$2,100
7.2 Permanent erosion controlLS1$1,500$1,500
7.3 Seeding & mulchingACRE0.20$1,000$200
7.4 Signage & delineationLS1$250$250
7.5 Final cleanupLS1$500$500
Subtotal 7.0$4,550
Permanent erosion control increased ($1,200 → $1,500) for creek-adjacent work. Native seed mix per conservation easement requirements.

Cost Breakdown

Base & Surface
37% $22,584
Drainage
21% $12,570
General Cond.
16% $9,500
Earthwork
11% $6,796
Finish Work
8% $4,740
Clearing
7% $4,047
Direct Cost
$60,237
+
Contingency (15%)
$9,036
=
Route B Total
$69,273

Line Items

1.0 General Conditions $9,500
ItemUnitQtyUnit PriceTotal
1.1 Mobilization / DemobilizationLS1$2,000$2,000
1.2 Surveying & StakingLS1$2,500$2,500
1.3 Erosion Control (Temporary)LS1$3,000$3,000
1.4 Traffic Control (approach work)LS1$500$500
1.5 Permits & FeesLS1$1,500$1,500
Subtotal 1.0$9,500
Standard erosion control — no creek protection needed. Standard permitting: Lane County approach permit, Oregon 811.
2.0 Clearing & Grubbing $4,047
ItemUnitQtyUnit PriceTotal
2.1 Clear & grub (light woods)ACRE0.39$6,500$2,535
2.2 Strip topsoil (6")CY252$6.00$1,512
Subtotal 2.0$4,047
Same spec as Route A: all cut trees and underbrush piled on-site per owner direction. Larger clearing area (0.39 vs 0.32 acre) due to longer road. Still well under 1-acre 1200-C threshold.
3.0 Earthwork $6,796
ItemUnitQtyUnit PriceTotal
3.1 Excavation (common)CY120$12.00$1,440
3.2 Fill placement & compactionCY60$9.00$540
3.3 Subgrade preparationSY1,133$3.50$3,966
3.4 Proof-rollLF850$1.00$850
Subtotal 3.0$6,796
Scaled proportionally to longer alignment. Route B terrain not yet walked — actual cut/fill could vary.
4.0 Drainage $12,570
ItemUnitQtyUnit PriceTotal
4.1 18" CMP cross-drain culvertsLF96$40.00$3,840
4.2 Culvert end sections (metal)EA8$275.00$2,200
4.3 Ditch excavation (V-ditch, uphill)LF850$5.50$4,675
4.4 Rock check damsEA5$275.00$1,375
4.5 Rip-rap (outlet protection)CY6$80.00$480
Subtotal 4.0$12,570
Four cross-drain culverts (one additional vs Route A due to longer road with more low points). No creek crossing — standard road drainage only.
5.0 Base Course $16,776
ItemUnitQtyUnit PriceTotal
5.1 Geotextile separation (non-woven)SY1,511$2.25$3,400
5.2 Aggregate base — delivered (3/4" minus)TON352$32.00$11,264
5.3 Aggregate base — place & compactTON352$6.00$2,112
Subtotal 5.0$16,776
62 additional tons vs Route A (352 vs 290 tons). This is the largest cost driver for Route B’s premium — more road length means more rock.
6.0 Surface Course $5,808
ItemUnitQtyUnit PriceTotal
6.1 Surface aggregate — delivered (3/4" minus)TON132$38.00$5,016
6.2 Surface aggregate — place & compactTON132$6.00$792
Subtotal 6.0$5,808
3" surface course of well-graded 3/4" minus crushed rock. 23 additional tons vs Route A.
7.0 Finish Work $4,740
ItemUnitQtyUnit PriceTotal
7.1 Shoulder gradingLF1,700$1.50$2,550
7.2 Permanent erosion controlLS1$1,200$1,200
7.3 Seeding & mulchingACRE0.24$1,000$240
7.4 Signage & delineationLS1$250$250
7.5 Final cleanupLS1$500$500
Subtotal 7.0$4,740
Standard erosion control and seeding. Native seed mix per conservation easement requirements.

Savings & Alternates

Potential savings apply to both routes. Add-alternates are priced for each route based on length.

Savings Opportunities

Owner-performed clearing$1.5K–$2K
Better soils (CBR>5)$2.5K–$4K
Owner hires surveyor$2K–$2.5K
Combine w/ nearby work$1.5K–$3K
Fewer culverts needed$1K–$2K

Add-Alternates

Chip seal surface+$7.5K–$9K
Passing turnout (40×8 ft)+$1.8K each
Dust palliative (MgCl)+$1.5K–$1.8K
Gate at road entrance+$1.5K

Shared Assumptions

Both routes share these assumptions. The estimate will be refined as site investigation data becomes available.

  1. Clay subgrade assumed (Jory/Bellpine series), CBR 3–6 wet. No site-specific borings yet.
  2. 8" base + 3" surface over geotextile. Designed for CBR < 5.
  3. No rock excavation. If rock encountered, pricing changes significantly.
  4. Dry season construction (June–September). Productivity factor 1.0.
  5. Private work — no prevailing wages, no performance bonds.
  6. Light woods — scattered trees, second-growth Douglas fir.
  7. Single-lane road, no passing turnouts. 20 ft clearing width.
  8. One-side ditch (uphill side) for full road length.
  9. Aggregate haul ~10 miles from Cottage Grove area quarries.
  10. No wetland impacts. If wetland fill required, add permits + mitigation.
  11. Disturbance under 1 acre (both routes) — below DEQ 1200-C threshold.
  12. Equipment is local. Minimal mobilization costs.
  13. All cut trees and underbrush piled on-site per owner direction. No off-site hauling.

Contingency Justification (15% Both Routes)

No soil borings yetHigh risk
No topographic surveyMedium risk
No wetland screeningMedium risk
Conservation easement unknownsMedium risk
Creek characteristics (Route A only)High risk
WeatherLow risk

Next Steps

The creek assessment is the single most important next step — it determines whether Route A or B is the right choice.

  1. Walk both alignments Verify terrain, tree density, drainage patterns, and wet areas for each route
  2. Assess the creek Determine if seasonal drainage is fish-bearing (ODFW screening), measure bankfull width, estimate flow. This is the key Route A vs B decision factor.
  3. Get soil data NRCS Web Soil Survey + hand auger borings at 3–5 locations per route ($500–$1,000 DIY)
  4. Survey Route B Confirm actual alignment length (currently estimated ~850 ft from map)
  5. Review conservation easement May impose requirements that favor one route. Get written approval before any disturbance.
  6. Confirm approach permit location Routes connect to Cerro Gordo Rd at different points; each needs its own approach review with Lane County
  7. Get aggregate quotes & contractor bids Local suppliers for delivered pricing; 2–3 bids from earthwork/road contractors, ideally for both routes