What – Straw, woodchips or fiber materials are applied to burned areas using ground or aerial application.
Purpose – By providing immediate ground cover, mulch is intended to reduce surface erosion, reduce downstream peak flows by absorbing rainfall, and secure seeds stored in the soil or applied as emergency treatment. Mulch also provides favorable moisture and temperature regimes for seed germination.
Effectiveness – Straw mulch was reported as highly effective in reducing surface erosion when application rates exceeded 60% ground cover, and sometimes effective in reducing runoff. Sites prone to high winds reported reduced effectiveness. A combination of mulching and seeding was reported as more effective than seeding alone in regards to germination, but not necessarily in regards to surface cover. Wood based mulches (manufactured products and shredded on-site trees) were equal to or more effective than straw mulch in reducing post-fire erosion.
Where
Cost – Straw aerial application $250–930 per acre; ground application $425–1200 per acre. Based on 1–2 tons per acre application rate (provides average mulch depth of 1–2 inches). Wood based aerial application $1500–2000. Additional factors include:
How to Link – See USDA BAER Catalog page 27 (PDF page 35).
What – Lightweight synthetic or organic mats (netting or blankets) staked to soil surface.
Purpose – Intended to provide temporary (several months to years) soil stability to special interest sites (e.g., heritage resources) until vegetation can establish. Mats also reduce soil temperature and provide moisture conservation.
Effectiveness – products are expensive, but effective when installed correctly.
Where
Cost – $0.35–1.00 per square yard + installation (labor). Additional factors include:
How to Links – See USDA BAER Catalog page 37 (PDF page 45); and NRCS Erosion Control Mats Fact Sheet.
What – Mini-dams built with straw, logs, or rocks; size depends on channel gradient.
Purpose – Temporary erosion control measure designed to trap and store sediment mobilized from hillslope. Also intended to reduce downcutting and attenuate peak flows.
Effectiveness – All types of checkdams appear to work better when implemented in gentle gradients, high in the watershed, and placed in a series. Problems with checkdams include complete structure failure from large storms. In-channel treatments without adjacent hillslope treatments are ineffective.
Where
Cost – $150–600 each. Additional factors include:
How to Links - See USDA BAER Catalog page 84 (PDF page 92); and NRCS Rock Check Dam Fact Sheet.
What – Altering road template. Outsloping is accomplished with an excavator, dozer, and grader (the excavator pulls back fill and places the material in the ditch; the dozer assists in moving and reshaping the road profile; and the grader completes the final profile).
Purpose – Disperse water along fill slope and reduce erosion; prevent concentration of flow on road surface that would otherwise cause rill, gully, and rut erosion.
Effectiveness – No effectiveness monitoring data is available. Informal observations indicate immediate and long-term facility and resource benefits, including less sediment delivered to stream channels and reduced road maintenance. In areas with highly erodible soils, outsloping roads with unvegetated soils may increase erosion. Outsloping is often combined with other road treatments, including rolling dips and armored crossings to control water.
Where
Cost – $2 per linear foot. Additional factors include:
How to Link – See USDA BAER Catalog page 106 (PDF page 144).
What – Combinations of organic fibers (e.g., wood shreds, paper, cotton, flax, etc.), tackifiers (i.e., glue), suspension agents, and seeds are mixed together with water and applied to the soil surface via ground or aerial applications.
Purpose – The matrix formed by hydromulch creates an immediate cover and holds moisture and seeds on steep slopes, which fosters seed germination while holding soil in place.
Effectiveness – Hydromulch may reduce sediment yields during the first few rainfall events (long-term effectiveness is unknown). Treatments are more effective on short slope lengths vs. longer slopes due to susceptibility to concentrated flows. This method is wind resistant. Multiple factors impact effectiveness (e.g., application rates, slope length and steepness, make/brand of tackifier).
Where
Cost – $2000–3000 per acre for aerial application; $1675–3000 per acre ground application. Additional factors include:
How to Links – See USDA BAER Catalog pages 15 and 22 (PDF pages 23 and 30); and NRCS Hydromulching Fact Sheet.
What – Logs are partially entrenched or/and staked to soil surface parallel to the contour.
Purpose – Intended to slow runoff, cause localized ponding, and capture and store eroded sediment when arranged in a bricklayer pattern on hillslopes.
Effectiveness – Studies indicated that log erosion barriers may reduce runoff, peak flows, and sediment yields for low intensity rain events (< 1.8” per hour), but are unlikely to have a significant effect for high intensity rain events. Sediment storage was reported to decrease by 10–15% with each successive rain event. Although the potential volume of sediment stored is dependent on slope, tree size and length, frequency, and use of berm traps, with proper implementation effective sediment storage and creation of microsites can be achieved.
Please note: some agencies, such as the US Forest Service, no longer endorse this method. However, other users have reported success with this method when logs are properly placed and secured. Please consider the cost, ease of application, and safety, and consult with experts in the post-fire treatment profession who can provide perspective, insight, guidance, and advice in an ever evolving field of practice.
Where
Cost – $420–1200 per acre. Additional factors include:
How to Links – See USDA BAER Catalog page 45 (PDF page 53); and NRCS Log Erosion Barriers Fact Sheet.
What – Directionally felling trees in a staggered herringbone pattern with tops pointed upstream.
Purpose – Intended to trap floating debris and suspended sediment. Over time, large woody material dissipates stream energy, provides cover and habitat for fish while providing long-term channel stability.
Effectiveness – Directional felling appears to work better when implemented in gentle gradients, high in the watershed, and placed in a series. Problems include complete structure failure from large storms. In-channel treatments without adjacent hillslope treatments are ineffective.
Where
Cost – $3500–4000 per mile of treatment, based on approximately 100 trees felled per mile of channel. Additional factors include:
How to Link – See USDA BAER Catalog page 90 (PDF page 98).
What – Altering road template.
Purpose – Rolling dips are used to drain water effectively from the road surface and prevent concentration of water.
Effectiveness – No effectiveness monitoring data exists on rolling dips. Rolling dips and outsloping are common treatments used to disperse flows and prevent stream diversion. Rolling dips are constructed easily with a dozer but often are too short in length, or too shallow to contain the expected flows. Often, a rolling dip/water bar is armored and used instead of a culvert upgrade because of its relatively low cost. However, it may erode away with strong currents in high discharge.
Where
Cost – $390–1200 per dip. Additional factors include:
How to Links – See USDA BAER Catalog page 110 (PDF page 118); and additional illustrations.
What – Felling, lopping, and then scattering trees and brush by hand or mechanical equipment.
Purpose – Intended to provide increased ground cover to reduce raindrop erosion.
Effectiveness – Scattering slash created by chain saw is generally ineffective due to slow labor production rates and the large amount of material needed for adequate soil cover. However, mechanized equipment (e.g., hydro ax) that masticates material is considered moderately effective.
Where
Cost – $220–1000 per acre. Additional factors include:
How to Link – See USDA BAER Catalog page 33 (PDF page 41).
What – Fiber rolls, commonly called wattles, are prefabricated rolls manufactured from rice straw and wrapped in degradable netting. In some cases, on-site woody debris can be rolled in netting to reduce costs. Rolls are ~ 9 inches in diameter and up to 25 feet long.
Purpose – Intended for low-surface flows not to exceed 1 cubic foot per second. They are not for stream channels or gullies. They are intended to reduce erosion by shortening the slope length to slow overland flow velocity as well as trap sediment and provide a seedbed for vegetative recovery.
Effectiveness – Studies indicated that erosion barriers may reduce runoff and sediment yields for low intensity rain events (< 1.8” per hour), but are unlikely to have a significant effect for high intensity rain events. Wattles reduced total runoff and peak flow rates (Robichaud et al. 2008 and 2010).
Where
Cost – $1100–4000 per acre. Additional factors include:
How to Links – See USDA BAER Catalog page 51 (PDF page 59); and NRCS Contour Wattles Fact Sheet.
What – Structure made of rocks, logs, or plant material installed in ephemeral channels at the grade.
Purpose – Provide grade control in channels that may become destabilized from increased storm runoff and velocities. Intended to prevent incising and downcutting in channel.
Effectiveness – Little quantitative data is available. This treatment may be most effective for areas of low or moderate flows. Grade stabilizers are likely to work better when implemented in gentle gradients, high in the watershed, and placed in a series. Problems include complete structure failure from large storms. In-channel treatments without adjacent hillslope treatments are ineffective.
Where
Cost – $250–4000 per structure depending on materials and installation method. Additional factors include:
How to Links – See USDA BAER Catalog page 94 (PDF page 102); and NRCS Grade Stabilizers Fact Sheet.
What – Structures such as armored rolling dip, overside drain, or imbricated (overlapping) rock-level spreader.
Purpose – Used on roads to control runoff across the road prism and to protect the road fill. Armored rolling dips provide increased water flow capacity when hydrologic analysis indicates the current pipe size is too small for the short-term increased storm runoff created by fire. Dips prevent stream diversion by safely channeling increased flows back into the channel. Overside drains (berm drains and down drains) are placed in stream crossings where no culvert or armoring exists and in locations where the embankment (fill slope) needs protection. Imbricated rock-level spreaders have been used on high standard roads including highways and county roads. The imbricated rock-level spreader is a permanent structure that is built with large rock placed in a stairstep (shingled) design on excavated benches with either little or no grade along the revetment’s length. The spreader protects the road fill from overland flows.
Effectiveness – Armored rolling dips are effective low-cost treatments when properly designed and implemented. Qualitative monitoring data of armored rolling dips found erosion problems when the dip was too short and when insufficient riprap was used on the fill slope. Overside drains fail if not properly designed, installed, and maintained. Initial qualitative monitoring indicated imbricated rock-level spreaders (rock armored overflow) are effective when they discharge directly onto a vegetated/wooded zone.
Where
Costs – Treatment vary in cost. Cost estimates can be developed based on material and installation requirements.
How to Link – See USDA BAER Catalog page 115 (PDF page 123).
What – Aerial and ground application of seed across large areas. Native seed mixes are preferred, but non-invasive, non-native seed mixes are also used, often with sterile annual grass seeds or cereal grain seeds.
Purpose – Intended to reduce soil erosion.
Effectiveness – Seeding was generally reported as ineffective (i.e., provided < 60% surface cover) the first year following fire and neutral in subsequent growing seasons following fire. However, when combined with mulching, the potential for germination may increase as a result of seed and moisture being held by mulch. Sterile annual seeds and cereal grain seeds that germinate can reduce soil erosion after fire, yet not compete with native grasses in subsequent years. Please note that seeding has the possibility for introducing invasive and noxious species, so be aware of this possibility.
Where
Cost – $20–170 per acre. However, trend analysis indicated costs increased over time (Peppin et al. 2011). Additional factors include:
How to Links – See USDA BAER Catalog page 64 (PDF page 72); and NRCS Seeding Fact Sheet.
What – a permeable fabric installed parallel to the contour and anchored with wooden stakes or metal t-posts.
Purpose – Intended to trap sediment and protect areas with high values at risk including heritage resources, water quality, and aquatic resources.
Effectiveness – Studies reported notably high effectiveness when fences were installed properly (i.e., anchored into soil and water allowed to pass through slowly while trapping sediment) and maintained (which requires significant effort and attention). Robichaud and Brown (2002) measured trap efficiency at over 90 %.
Where
Cost – $50 per roll (material); $150–250 labor for each fence installation. Additional factors include:
How to Links – See USDA BAER Catalog page 56 (PDF page 64); and NRSC Silt Fence Fact Sheet.
What – Reinforcement of streambank with protective covering, such as rocks, vegetation or engineering materials (including boulders, riprap, and gabion baskets).
Purpose – Reduce bank cutting and erosion due to peak flows.
Effectiveness – No quantitative effectiveness monitoring data exists for this treatment. Streambank armoring is likely to work better when implemented in gentle gradients, high in the watershed, and placed in a series. Problems include complete structure failure from large storms. In-channel treatments without adjacent hillslope treatments are ineffective.
Where
Cost – moderate to high (no specific estimates are available). Costs factors listed below:
How to Link – See USDA BAER Catalog page 97 (PDF page 105); and National Engineering Handbook - Streambank Armor Protection.
What – Culverts are temporarily removed and replaced with natural fords, vented ford pipes, and low water bridges during extreme runoff events.
Purpose – To prevent stream diversion and keep water in its natural channel. This prevents erosion of the road fill, reduces adverse effects to water quality, and maintains access to areas once storm runoff rates diminish.
Effectiveness – Ford crossings effectively eliminate loss of water control at road/stream crossing. However, poor design or implementation can result in damage to infrastructure and reduced water quality. Informal monitoring indicates that flexible structures adjust to changes and are not prone to undercutting. Boulder or riprap structures are long enough to avoid being outflanked by high flows. Jersey barriers are less effective as an endwall material since they are not flexible.
Where
Costs – $500–2500 for an unvented ford; costs increase for a vented ford or low-water bridge. Additional factors include:
How to Link – See USDA BAER Catalog page 122 (PDF page 122).
What – Hand tools or mechanical equipment are used to break up and loosen topsoil to increase surface roughness.
Purpose – Intended to break down hydrophobic layer, prepare seedbed, and increase infiltration rate.
Effectiveness – Generally, this treatment did not provide significant improvement (e.g., reduced sediment yield) as compared to no treatment (Rough 2007).
Where
Cost – $245–300 per acre for hand crew; $50 per acre for ATV use. Additional factors include:
How to Links – See USDA BAER Catalog page 60 (PDF page 68); and NRCS Mechanical Scarification Fact Sheet.
What – Engineered structures such as j-hooks, rock barbs, and single- or double-wing deflectors.
Purpose – Designed to direct increased streamflows and velocities away from unstable banks or structures of value such as a road parallel to the channel.
Effectiveness – There is no documented effectiveness monitoring data for this treatment. Channel deflectors are likely to work better when implemented in gentle gradients, high in the watershed, and placed in a series. Problems include complete structure failure from large storms. In-channel treatments without adjacent hillslope treatments are ineffective.
Where
Cost – Treatment costs are variable depending on the structure installed. Costs factors listed below:
How to Links – See USDA BAER Catalog page 99 (PDF page 107); and Flow Control Structures.
(Before modification)
(After modification)
What – Culvert modification addresses flooding and debris concerns as a result of fire. Usually involves upgrading the culvert size for increased runoff and associated bedload and debris.
Purpose – By increasing the flow and debris passage capacity, road damage is prevented or reduced.
Effectiveness – Evaluation of this treatment is only qualitative. The treatment rates ‘well’ when new culverts are installed prior to the first rains. ‘Poor’ ratings reflect the inability to perform the upgrade in a timely manner or when culverts are still not large enough to handle runoff events.
Where
Costs – $20,000 to $150,000 per structure. Additional factors include:
How to Link – See USDA BAER Catalog page 128 (PDF page 136).
What – Specially engineered and constructed emergency basin for storing large amounts of sediment moving in an ephemeral stream channel. Designed to trap at least ~ 50–70 percent of expected flows.
Purpose – Designed to store runoff and sediment; often the last recourse to prevent downstream flooding, sedimentation, or threats to human life and property. Provide immediate protection from floodwater, floatable debris, sediment, boulders, and mudflows.
Effectiveness – No quantitative information is available on effectiveness. Debris basins are considered to be a last resort because they are expensive to construct and require commitment to long-term repeated maintenance following runoff events.
Where
Cost – Expensive; costs depend on the following factors:
How to Links – See USDA BAER Catalog page 102 (PDF page 110); NRCS Sediment Basin Fact Sheet; and Debris Dam Publication.
What – A debris rack is a structure placed across a stream channel to collect debris before it reaches a culvert entrance. A debris deflector is a structure (usually V-shaped with apex pointed upstream) placed at the culvert inlet to route the major portion of debris away from the culvert entrance.
Purpose – Designed to protect culverts from catastrophic failure by catching floatable debris that otherwise would likely plug culverts and cause stream diversion. By protecting culverts from failing, these structures protect transportation infrastructure, public safety, and downstream resource values.
Effectiveness – No quantitative data exists on the effectiveness of debris structures. However, anecdotal information indicates they can be effective with proper implementation and maintenance. Problems can occur if the design structure is too small for the stormflows and associated debris.
Where
Cost – $100–4000 depending on material. Log racks built with onsite burned logs are economically efficient. Structures constructed with heavy rail or steel range from $3000 to $30,000 or more depending on the size and materials required. Additional factors include:
How to Link – See USDA BAER Catalog page 134 (PDF page 142).
What – Riser pipes function to sieve debris and allow passage of water. Riser pipe allows accumulation of bedload sediments released from a drainage due to the loss of soil cover and reduced infiltration from water repellant soils. The sediment and ash captured in the basin can be removed with a backhoe.
Purpose – Risers are used to protect road infrastructure, especially those with large fill, from failure. Riser pipes help prevent culverts from plugging with sediment and floating debris. Pipes capture sediment and reduce downstream impacts to water quality. Riser pipes also reduce peak flows by storing water and sediment.
Effectiveness – No formal effectiveness monitoring data exists for risers. However, reports indicate risers performed well when maintained. Problems occurred when structures were not routinely checked and debris was not removed from the basin. Risers are temporary treatments that are easily disassembled when no longer needed. Risers are installed quickly and at a low cost.
Where
Cost – $750–1400 for labor and material. Additional factors include:
How to Link – See USDA BAER Catalog page 140 (PDF 148).
What – Mechanical equipment is used to clean out organic debris and sediment deposits in stream channels, above culverts, and in catchment basins ahead of anticipated runoff events.
Purpose – To prevent organic debris and sediment deposits from becoming mobilized in debris flows and flood events. Intended to protect transportation and facility infrastructure.
Effectiveness – No quantitative effectiveness monitoring data is available on catchment basin cleanout. However, anecdotal information suggested the treatment is effective.
Where
Cost – $200–2000 for each basin. Additional factors include:
How to Link – See USDA BAER Catalog page 145 (PDF page 153).
What – On-the-ground inspection and clean out, if necessary, of critical infrastructure during, after, or between precipitation events that may result in loss of water control.
Purpose – Intended to keep culverts and drainage structures functioning on roads where access is required by cleaning sediment and debris from the inlet. The treatment is used in lieu of more costly upgrades that are not feasible due to expense or time frame. Storm inspection and response performed during runoff events should be conducted with caution.
Effectiveness – No formal effectiveness monitoring data exists on storm inspection and response. Informal observations indicate cost effectiveness because some road problems are avoided with timely clearing and cleaning of road crossings. However, challenges include maintaining a dedicated inspection team over time, and where excessive areas to patrol result in inadequate coverage.
Where
Cost – Equipment rates per day: backhoe $390; front-end loader $465; four-person crew $970. Additional factors include:
How to Link – See USDA BAER Catalog page 150 (PDF page 158).
What – Trail stabilization methods include rubber belt and rock waterbars, rock spillways, and rolling dips.
Purpose – Designed to provide drainage and stability to reduce trail damage and erosion.
Effectiveness – No quantitative data exists on the effectiveness of this treatment.
Where
Cost – $1000–3000 per mile. Additional factors include:
How to Link – See USDA BAER Catalog page 153 (PDF page 161).
What – Mechanical equipment such as an excavator or dozer is used to decommission unauthorized roads that are destabilized as a result of loss of vegetation following high burn severity.
Purpose – Intended to improve infiltration, restore hillslope hydrology, and reduce erosion following subsoiling (tilling), recontouring road fill, and restoring drainage through the road prism using mechanical equipment.
Effectiveness – No quantitative data is available on soil erosion rates. However, visual inspection revealed that treatment objectives to improve infiltration and reduce erosion by restoring the slope were achieved in treated areas.
Where
Cost – $7000–8000 per mile. Additional factors include:
How to Link – See USDA BAER Catalog page 160 (PDF page 168).