Erosion Control Cost Calculator: Silt Fence Cost Per Foot

With the defaults, 400 LF of silt fence, protection at 2 storm inlets and 1 stabilized construction entrance come to $2,800: $1,400 for the silt fence, $500 for the inlets, $600 for the entrance and $300 for mobilization. That is $7.00 per LF of silt fence, because the cost per foot is the whole job divided by the feet of silt fence and sock.

The fixed items weigh more on a short fence line. With 2 inlets and 1 entrance, 200 LF of silt fence comes to $2,100 ($10.50 per LF), 1,000 LF to $4,900 ($4.90 per LF) and 2,000 LF to $8,400 ($4.20 per LF). Silt fence alone, with no inlets or entrance, is $1,700 for 400 LF, or $4.25 per LF with mobilization.

Silt sock costs more per foot than silt fence at the default prices: $8.25 against $3.50. The two prices differ in scope: the silt sock price comes from bids that included maintaining the sock, while the silt fence price is set against highway items that price maintenance separately. Using 400 LF of silt sock in place of the silt fence on the default job comes to $4,700, or $11.75 per LF. Erosion control blanket is priced per square yard, so 1,000 SY adds $2,380 and brings the default job to $5,180.

The $500 minimum is a floor that sets the price only when the job adds up to less. 50 LF of silt fence with mobilization adds up to $475, so the price is $500. At the default prices that happens for silt fence alone up to 57 LF.

The calculator prices silt fence at $3.50 per LF, the same price the land clearing calculator uses. Wisconsin DOT’s Average Unit Price List (10/21/2025) gives its Silt Fence item (628.1504) at $2.15, $2.05 and $1.99 per LF for fiscal years 2023 to 2025. South Dakota DOT’s 2024 Bid Item Price Report gives Low Flow Silt Fence at $5.00 per foot as the average low bid and $4.66 as the average of the three lowest bids, over 171,975 ft on 40 contracts, and High Flow Silt Fence at $5.71 and $4.93 over 71,869 ft on 36 contracts.

So the $3.50 default sits between the two states: at Wisconsin’s FY2025 average, the 400 LF line would be $796 instead of $1,400, and at South Dakota’s low-flow average low bid it would be $2,000. The lists name each item but do not say what it includes; South Dakota prices removal as a separate item. A state DOT price is one state’s price for highway lettings: South Dakota’s 171,975 ft of low-flow silt fence came to about 4,300 ft per contract. The calculator carries the cost of moving in for a small job in its mobilization charge and minimum, both estimates.

Maintenance has no line of its own in the calculator. The silt sock price already includes it, because Madison’s bids were to provide, install and maintain the sock. For silt fence, both states price maintenance separately: Wisconsin DOT’s Silt Fence Maintenance item averaged $0.03 to $0.11 per LF in fiscal years 2023 to 2025, and South Dakota DOT’s Repair Silt Fence averaged $2.05 per foot as the average low bid in 2024. If your job needs silt fence repairs or sediment cleanout during construction, add them as an extra line in bid mode.

Inlet protection prices depend on the device. Madison’s Contract 8742 (Rutledge Street Assessment District - 2024, bid tab dated 7/18/24) had four bids for rigid-frame inlet protection, provided and installed, of $316.78, $350, $275 and $275 each over 48 inlets. South Dakota DOT’s 2024 Sediment Control at Inlet with Frame and Grate averaged $243.99 as the average low bid and $186.93 as the average of the three lowest bids. Other items cost less: Wisconsin DOT’s Inlet Protection Types A to D averaged $54.59 to $126.35 each in fiscal years 2023 to 2025. The calculator uses $250 per inlet, our pick between the South Dakota and Madison frame-type items; at $126.35 the default job would be $2,553, and at $316.78 it would be $2,934.

Madison’s four bids for a construction entrance were $364.51, $660, $300 and $1,000 each over 7 entrances, and Wisconsin DOT’s Tracking Pads item averaged $699.30, $669.30 and $351.05 in fiscal years 2023 to 2025. The calculator uses $600, our pick between Madison’s median bid (about $512) and Wisconsin DOT’s median tracking pad average ($669.30). South Dakota DOT’s 2024 Construction Entrance item was much higher, $4,320.57 as the average low bid over 51 entrances; the report does not say what size or make-up the item had, so it is not used.

The silt sock price is the median of Madison’s four bids for 8 in silt sock, provided, installed and maintained, of $9.00, $7.00, $9.95 and $7.50 per LF over 65 LF. South Dakota DOT’s 2024 12 in Diameter Erosion Control Wattle averaged $8.91 per foot as the average low bid and $8.15 as the average of the three lowest bids, over 129,450 ft on 58 contracts. The blanket price is the median of Madison’s four bids for Class I, Type A organic erosion matting ($2.25, $2.80, $1.85 and $2.50 per SY over 5,700 SY), rounded to $2.38. South Dakota DOT’s Type 2 and Type 3 Erosion Control Blanket averaged $2.95 and $3.61 per SqYd as average low bids in 2024.

Madison is one city job with small quantities, 65 LF of silt sock and 7 entrances, so treat those prices as one data point. The silt fence removal price rests on South Dakota DOT alone, and the inlet protection removal price on Madison’s four bids alone.

Turn on removal to price taking the silt fence, silt sock and inlet protection out at the end of the job. Silt fence removal is $1.20 per LF, between South Dakota DOT’s 2024 Remove Silt Fence average low bid of $1.19 and its three-lowest average of $1.22 (81,588 ft on 48 contracts). Silt sock removal is $3.00 per LF: Madison’s item was “remove & restore”, bid at $8.00, $4.00, $3.00 and $3.00, and South Dakota’s Remove Erosion Control Wattle averaged $2.41 and $2.67. Inlet protection removal is $36.50 per inlet, the median of Madison’s rigid-frame removal bids of $48, $50, $25 and $20. On the default job removal adds $553, for a total of $3,353.

Removal has no line for the construction entrance or the erosion control blanket, because no source we opened prices their removal. The calculator charges mobilization once; if removal is a separate trip, raise the mobilization in the pricing section.

The estimate covers installed erosion and sediment control items only. It leaves out the stormwater pollution prevention plan (SWPPP) document and permit fees, inspections, seeding and hydroseeding, and sediment basins. Ask your engineer or the permitting agency what your site needs.

Run the calculator from the quantities on the erosion control plan, then switch to contractor bid mode. In bid mode the default job’s $2,800 becomes a customer price of $3,696 with 10% overhead and 20% profit.

The unit prices come from public bids, which are contractors’ selling prices, so they already include overhead and profit. Replace them with your own costs in the pricing section before you add markup, or the markup counts them twice. There is no material tax on this job, because every line is priced installed.