National Marine Fisheries Service 

National Gravel Extraction Guidance 

A review of the effects of in- and near-stream gravel 

extraction on anadromous fishes and their habitats, 

with recommendations for avoidance, minimization, 

and mitigation 

D. B. Packer, K. Griffin, and K. E. McGlynn 

U.S. Department of Commerce 

National Oceanic and Atmospheric Administration 

National Marine Fisheries Service 

NOAA Technical Memorandum NMFS-F/SPO-70 

September 2005
National Marine Fisheries Service 

National Gravel Extraction Guidance

A review of the effects of in- and near-stream gravel 

extraction on anadromous fishes and their habitats, 

with recommendations for avoidance, minimization, 

and mitigation

D. B. Packer, K. Griffin, and K. E. McGlynn

NOAA Fisheries – Office of Habitat Conservation 

NOAA Technical Memorandum NMFS-F/SPO-70 

September 2005

U.S. Department of Commerce 

Carlos M. Gutiérrez, Secretary 

National Oceanic and Atmospheric Administration 

Vice Admiral Conrad C. Lautenbacher, Jr., USN (Ret.) 

Under Secretary for Oceans and Atmosphere 

National Marine Fisheries Service 

William T. Hogarth, Assistant Administrator for Fisheries
Suggested citation: 

Packer, D. B., K. Griffin, and K. E. McGlynn. 2005. National Marine Fisheries Service National 

Gravel Extraction Guidance. U.S. Dep. Commerce, NOAA Tech. Memo. NMFS-F/SPO-70, 27p. 

A copy of this report may be obtained from:

Office of Habitat Conservation 

NMFS, NOAA 

1315 East-West Highway, F/HC2 

Silver Spring, MD 20910 

Or online at: 

http://www.nmfs.noaa.gov/habitat/habitatprotection/anadfish/gravel.htm 
 NATIONAL MARINE FISHERIES SERVICE 

 NATIONAL GRAVEL EXTRACTION GUIDANCE 

I. INTRODUCTION 

The National Marine Fisheries Service (NMFS) is responsible for protecting, managing and 

conserving marine, estuarine, and anadromous fishes and their habitats. The watersheds of the 

United States provide essential spawning and rearing habitat for anadromous fishes including 

salmon, shad, sturgeon, and striped bass. 

A national guidance document on gravel extraction is necessary because extraction in and near 

streams can cause many adverse impacts to anadromous fishes and their habitats. Potential 

impacts include: direct harm to trust species; loss or degradation of spawning, rearing, resting, 

and staging habitat; migration delays and/or blockages; channel widening, shallowing, or 

ponding; loss of channel stability; loss of pool/riffle structure; increased turbidity and sediment 

transport; increased bank erosion and/or stream bed downcutting; and loss or degradation of 

riparian habitat. The impacts can extend far beyond the mining site, and stream recovery can 

take decades. 

In the context of Federal trust responsibilities, as defined in the collective body of Federal law 

and regulations, NMFS must ensure that Federal actions, including authorizations to conduct 

gravel extraction operations, avoid, minimize, or mitigate to the greatest extent possible, any 

adverse impacts to anadromous fishes and their habitats. NMFS has been delegated the 

responsibility and authority under several Federal laws to address the effects of gravel extraction 

activities when the activities affect marine or anadromous fish under NMFS jurisdiction or their 

habitats. These authorities are summarized in the Appendix I, and include the Endangered 

Species Act (ESA), Clean Water Act (CWA), National Environmental Policy Act (NEPA), 

Magnuson-Stevens Fishery Conservation and Management Act (Magnuson-Stevens Act), and 

the accompanying implementing regulations of each law. 

This document revises and replaces NMFS’ 1996 National Gravel Extraction Policy. The 

objectives of the NMFS Gravel Guidance are to (1) assist NMFS staff in determining whether 

proposed gravel extraction operations will be conducted in a manner consistent with Federal law, 

while (2) avoiding, minimizing, and mitigating any adverse impacts to anadromous fishes and 

their habitats. NMFS recommends that gravel extraction operations not interfere with 

anadromous fish migration, spawning, or rearing, or negatively impact viable existing or historic 

anadromous fish habitat. Further, it is recommended that individual gravel extraction operations 

be judged in the context of their spatial, temporal, and cumulative impacts, and that potential 

impacts to habitat be viewed from a watershed management perspective. Although this Guidance 

applies nationwide, it is not to be regarded as static or inflexible, as project recommendations 

must be made specific to individual sites, streams, and watersheds. 

This Guidance does not specify the measures, if any, that would need to be implemented by 

parties engaged in gravel extraction activities in any given case to comply with applicable 

statutory requirements. In formulating its recommendations or prescriptions, NMFS will 
 

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determine the acceptable means of demonstrating compliance with statutory requirements based 

on information available to the agency, as appropriate under the circumstances presented. As 

such, the language of this Guidance for NMFS staff should not be read to establish any binding 

requirements on agency staff or the regulated community. 

II. SCOPE OF GRAVEL GUIDANCE 

This Guidance document addresses freshwater and tidal reaches of rivers and streams, tidal 

sloughs, and their associated wetlands and riparian zones where anadromous fish are currently or 

were historically present. Gravel extraction, as well as sand mining and dredging, also occurs in 

marine habitats such as the lower reaches of large tidal streams, estuaries and offshore. Marine 

extraction operations generally raise different concerns than those in streams. Although many 

elements of this Guidance are germane to all areas where gravel extraction occurs, the primary 

focus of this Guidance is extraction of gravel in streams rather than in marine environments. 

The types of gravel extraction activities referred to in this Gravel Guidance generally entail 

commercial gravel mining (i.e., removing or obtaining a supply of gravel for industrial uses, 

such as road construction material, concrete aggregate, fill, and landscaping). Gravel can also be 

removed from stream channels for navigation and flood control purposes. Gravel extraction often 

occurs at multiple times and at multiple sites along a given stream, resulting in impacts that are 

likely to be both chronic and cumulative. When the rate of gravel extraction exceeds the rate of 

natural deposition over an extended time period, a net cumulative loss of gravel occurs (Oregon 

Water Resources Research Institute [OWRRI] 1995). 

This Gravel Guidance document addresses three types of instream gravel mining, described as 

dry-pit and wet-pit mining in the active channel, and bar skimming (or “scalping”) (Kondolf 

1993, 1994a, 1997, 1998a). Dry-pit refers to excavation on dry ephemeral stream beds and 

exposed bars with conventional bulldozers, scrapers, and loaders. Wet-pit mining involves the 

use of a dragline or hydraulic excavator to remove gravel from below the water table or in a 

perennial stream channel. Bar skimming or scalping removes the surface from gravel bars 

without excavating below the low water flow level. 

In addition to the instream mining described above, this Guidance document also addresses 

another method, which involves the excavation of pits on the adjacent floodplain or river terraces 

(Kondolf 1993, 1994a, 1997, 1998a). Pits located above the water table are also known as drypits, whereas wet-pits are below, depending on the elevation of the floodplain or terrace relative 

to the baseflow water elevation of the channel. The isolation of these pits from an adjacent active 

channel may be only short-term. During a sudden change in channel course during a flood, or as 

part of gradual migration, the channel may shift into the gravel pits (Kondolf 1998a). Because 

floodplain pits can become integrated into the active channel, Kondolf (1993, 1994a) suggests 

that they should be regarded as part of the active channel if considered on a time scale of 

decades, and managed accordingly. 
 

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III. ENVIRONMENTAL EFFECTS OF GRAVEL EXTRACTION 

Extraction of alluvial material from within or near a stream bed has a direct impact on the 

stream’s physical habitat parameters such as channel geometry, bed elevation, substrate 

composition and stability, instream roughness elements (large woody debris, boulders, etc.), 

depth, velocity, turbidity, sediment transport, stream discharge, and temperature (Rundquist 

1980; Pauley et al. 1989; Kanehl and Lyons 1992; Kondolf 1994a, 1994b, 1997, 1998a; OWRRI 

1995; Brown et al. 1998; Florsheim et al. 1998; Meador and Layher 1998; Langer 2001, 2003). 

OWRRI (1995) states that: 

Channel hydraulics, sediment transport, and morphology are directly affected by 

human activities such as gravel mining and bank erosion control. The immediate 

and direct effects are to reshape the boundary, either by removing or adding 

materials. The subsequent effects are to alter the flow hydraulics when water 

levels rise and inundate the altered features. This can lead to shifts in flow 

patterns and patterns of sediment transport. Local effects also lead to upstream 

and downstream effects. 

Altering these habitat parameters can have deleterious impacts on instream biota, food webs, and 

the associated riparian habitat (Sandecki 1989; Kanehl and Lyons 1992; Koski 1993; Spence et 

al. 1996; Brown et al. 1998). For example, impacts to anadromous fish populations due to gravel 

extraction can include reduced fish populations in the disturbed area, replacement of one species 

by another, replacement of one age group by another, or a shift in the species and age 

distributions (Moulton 1980). Changes in physical habitat characteristics of aquatic systems can 

alter competitive interactions within and among species; similarly, changes in temperature or 

flow regimes may favor species that prey on anadromous fish populations (Spence et al. 1996). 

In general terms, Rivier and Seguier (1985) suggest that the detrimental effects to biota resulting 

from bed material mining are caused by two main processes: (1) alteration of the flow patterns 

resulting from modification of the river bed, and (2) an excess of suspended sediment. OWRRI 

(1995) adds: 

Disturbance activities can disrupt the ecological continuum in many ways. Local 

channel changes can propagate upstream or downstream and can trigger lateral 

changes as well. Alterations of the riparian zone can allow changes in-channel 

[sic] conditions that can impact aquatic ecosystems as much as some in-channel 

activities. 

One consequence of the interconnectedness of channels and riparian systems is 

that potential disruptions of the riparian zone must be evaluated when channel 

activities are being evaluated. For example, aggregate mining involves the 

channel and boundary but requires land access and material storage that could 

adversely affect riparian zones; bank protection works are likely to influence 

riparian systems beyond the immediate work area. 

It should be emphasized that cobble and gravel substrates are in and of themselves extremely important 

habitat for anadromous fish, including salmon, shad, striped bass, and sturgeon. Gravel habitat provides 
 

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protective crevices and well-oxygenated interstitial spaces that are important for anadromous fish egg 

hatching. Gravel habitat also contains rich assemblages of benthic nutrients used as food for developing 

fish larvae, and provides macroinvertebrate food sources for post-larval juveniles. 

The potential effects of gravel extraction activities on stream morphology, riparian habitat, and 

anadromous fishes and their habitats are summarized as follows: 

1. Instream gravel mining can disrupt the preexisting balance between sediment supply and 

transporting capacity, and can result in channel incision and bed degradation (Kondolf 1997, 

1998a; Florsheim et al. 1998; Meador and Layher 1998; Langer 2001, 2003). This is partly because 

gravel “armors” the bed, stabilizing banks and bars, whereas removing this gravel causes erosion 

(Lagasse et al. 1980; OWRRI 1995; Kondolf 1997, 1998a). Degradation and erosion can extend 

upstream and downstream of an individual extraction operation, and can result from bed mining 

either in or above the low-water channel (Collins and Dunne 1990; Kanehl and Lyons 1992; 

Kondolf 1994a, 1994b, 1997, 1998a; OWRRI 1995; Pringle 1997; Brown et al. 1998). For example, 

headcutting (upstream erosion), increased velocities, concentrated flows, and bank undercutting with 

subsequent loss of riparian habitat can occur upstream of the extraction site due to a steepened river 

gradient (Kanehl and Lyons 1992; OWRRI 1995; Kondolf 1997; Pringle 1997), resulting in the 

release of additional sediment to downstream reaches, where the channel may aggrade and become 

unstable (Kondolf 1997). Accelerated delivery of sediment from upstream can falsely indicate 

recruitment in balance with removal. Degradation can deplete the entire depth of gravel on a channel 

bed, exposing other substrates that may underlie the gravel, reducing the amount and quality of 

usable anadromous spawning and rearing habitat (Collins and Dunne 1990; Kondolf 1994a, 1997, 

1998a; OWRRI 1995). For example, gravel removal from bars may cause erosion if they 

subsequently receive less bed material from upstream than is being carried away by fluvial transport 

(Collins and Dunne 1990). Thus, gravel removal not only impacts the extraction site, but also may 

reduce gravel delivery to downstream spawning and rearing areas (Pauley et al. 1989; Brown et al. 

1998). Gravel mining itself often selectively removes gravels of approximately the same sizes as 

needed by salmonids for spawning (median diameters between 15 and 45 mm [Kondolf and Wolman 

1993; see also Kondolf 2000]), again reducing the amount of usable spawning and rearing habitat.

2. Instream gravel extraction can increase suspended sediment, sediment transport, water 

turbidity, and gravel siltation (Kanehl and Lyons 1992; OWRRI 1995; Kondolf 1997). The 

most significant change in the sediment size distribution resulting from gravel removal is a 

decrease in sediment size caused by fine material deposition into the mining site (Rundquist 

1980). Brown et al. (1998) also note that the fine material can travel long distances 

downstream as a plume of turbidity while the gravel is being removed and, during floods, 

turbidity is likely to be higher than normal for even longer distances downstream due to the 

higher flow rate and increased entrainment of sediments as a result of channel deformation or 

armor layer removal. As reviewed by Everest et al. (1987), fine sediments in particular are 

detrimental to salmonid redds (nests) because (1) interstitial spaces blocked by deposited silt 

prevents oxygenated water from reaching the incubating eggs within the redd, and inhibits 

the removal of waste metabolites; (2) embryos or sac fry can be smothered by high 

concentrations of suspended sediments that enter the redd; and (3) emerging fry can become 

trapped if enough sediment is deposited on the redd (Koski 1966, 1981; Chapman 1988; 

Reiser and White 1988; Waters 1995). High silt loads may also inhibit larval, juvenile, and 
 

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adult behavior, migration, or spawning (Snyder 1959; Cordone and Kelly 1961; Koski 1975; 

Bisson and Bilby 1982; Berg and Northcote 1985; Bjornn and Reiser 1991; Kanehl and 

Lyons 1992; Servizi and Martens 1992; OWRRI 1995). Excessive amounts of suspended 

material can abrade the protective slime coatings on the surface of the fish and their gills, 

which can lead to increased bacterial and fungal infections (Cordone and Kelly 1961; Rivier 

and Seguier 1985). Increased suspended sediments may block vision and impede feeding 

(Sigler et al. 1984; Rivier and Seguier 1985). Siltation, substrate disturbances and increased 

turbidity also negatively affect the invertebrate food sources of fishes and severely alter the 

aquatic food web, thus affecting the growth and survival of the fish (Kanehl and Lyons 1992; 

OWRRI 1995; Spence et al. 1996; Brown et al. 1998).

3. Bed degradation can change the morphology of the channel and decreases channel 

stability (Moulton 1980; Rundquist 1980; Sullivan et al. 1987; Collins and Dunne 1990; 

Kanehl and Lyons 1992; Kondolf 1994a, 1994b, 1997; OWRRI 1995; Brown et al. 1998; 

Florsheim et al. 1998). Gravel extraction can cause a diversion or a high potential for 

diversion of flow through the gravel removal site (Rundquist 1980). Mined reaches of a river 

or stream that show decreased depth and/or surface flow, which can occur where the flow is 

spread over a wide area and there is considerable intergravel flow, could block fish migration 

during periods of low flows (Moulton 1980). This could be caused by gravel bar skimming in 

particular (see Environmental Effect Number 4, below), and may compound problems in 

many areas where flows may already have been altered by hydropower operations, irrigation, 

or other human uses. Even if the gravel extraction activity is conducted away from the active 

river channel during low water periods (see Environmental Effect Number 8, below), 

substrate stability and channel morphology outside the excavated area’s perimeter could be 

affected during subsequent high water events (Kondolf 1997, 1998a). 

4. Gravel bar skimming can significantly impact aquatic habitat. Bar skimming creates a 

wide, flat cross section, eliminating confinement of the low flow channel, which can then 

result in a thin sheet of water at baseflow (Kondolf 1994a, 1997). Sediment transport 

efficiency may be reduced through the unconfined reach due to the increased width-to-depth 

ratio, causing deposition and subsequent instability (Kondolf 1998a). Removal of the bar 

may alter channel hydraulics upstream as well as at the gravel extraction site (Kondolf 

1998a). Bar skimming can also remove the gravel “pavement,” leaving the finer subsurface 

particles vulnerable to entrainment (erosion) at lower flows (Kondolf 1994a, 1998a; OWRRI 

1995). A related effect is that bar skimming lowers the overall elevation of the bar surface 

and may reduce the threshold water discharge at which sediment transport occurs (OWRRI 

1995). Salmon redds downstream are thus susceptible to deposition of displaced alluvial 

material, resulting in egg suffocation or suppressed salmon fry emergence, while redds 

upstream of scalped bars are vulnerable to regressive erosion (Pauley et al. 1989). Gravel bar 

skimming also appears to reduce the amount of side channel areas, which can reduce and/or 

displace juvenile salmonid fishes that use this habitat (Pauley et al. 1989). All these effects 

can be particularly problematic if upstream flows are already reduced by diversions, dams, or 

other human activities.

5. Operation of heavy equipment in the channel bed can directly destroy spawning 

habitat, rearing habitat, the juveniles themselves, and macroinvertebrates; can produce 
 

6 

increased turbidity and suspended sediment downstream; and has the potential to cause 

toxic chemical spills (Forshage and Carter 1973; Kondolf 1994a). Heavy equipment usually 

crosses stream channels where the stream is shallowest, at riffles. Riffle habitat is important 

for juvenile salmonids (Bradford and Higgins 2001) because, for example, the juveniles often 

respond to disturbances by entering the interstitial spaces between the gravel substrate at 

riffles (Shrivell 1990; Meehan and Bjornn 1991). These pore spaces in the gravel substrate 

are important sources of cover or refuge (Raleigh et al. 1984). Therefore, juveniles in this 

riffle habitat could be susceptible to crushing from heavy equipment. Additional disturbances 

to redds may occur from increased foot and vehicle access to spawning sites, due to access 

created initially for gravel extraction purposes (OWRRI 1995). Also, heavy equipment is 

powered by diesel fuel and lubricated by other hazardous petroleum products, leading to the 

potential for toxic chemical spills.

6. Stockpiles of overburden and gravel left or abandoned in the channel or floodplain can 

alter channel hydraulics during high flows. During high water, the presence of stockpiles 

can cause fish blockage or entrapment, and fine material and organic debris may be 

introduced into the water, resulting in downstream sedimentation (Follman 1980). The 

stockpiles may also concentrate flows on the stream bed or floodplain resulting in increased, 

localized erosion.

7. Removal or disturbance of instream roughness elements during gravel extraction 

activities can negatively affect both quality and quantity of anadromous fish habitat. 

Instream roughness elements, including the gravel itself and large woody debris, play a 

major role in providing structural integrity and complexity to the stream or river ecosystem 

and provide habitat critical for anadromous fish (Koski 1992; Naiman et al. 1992; Franklin et 

al. 1995; Murphy 1995; OWRRI 1995; Abbe and Montgomery 1996; Collins and 

Montgomery 2002; Collins et al. 2002). These elements are important in controlling channel 

morphology and stream hydraulics; in regulating the storage of sediments, gravel and 

particulate organic matter; and in creating and maintaining habitat diversity and complexity 

(Franklin 1992; Koski 1992; Murphy 1995; OWRRI 1995). Large woody debris in streams 

creates pools and backwaters that fish use as foraging sites, critical overwintering areas, 

refuges from predation, and spawning and rearing habitat (Koski 1992; Maser and Sedell 

1994; OWRRI 1995). Large wood jams at the head of gravel bars can anchor the bar and 

increase gravel recruitment behind the jam (OWRRI 1995). Loss of large woody debris from 

gravel bars can also negatively impact aquatic habitat (Weigand 1991; OWRRI 1995). The 

importance of large woody debris has been well documented, and its removal results in an 

immediate decline in salmonid abundance (e.g., see citations in Koski 1992; Franklin et al. 

1995; Murphy 1995; OWRRI 1995). It is also important to remember that gravel deposits are 

themselves instream roughness elements, which is key to recognizing that the same type of 

effects apply (i.e., linking hydraulics and habitat is also applicable for gravel deposits 

underwater or on bars).

8. Dry pit and wet pit mining in floodplains may reduce groundwater elevations, reduce 

stream flows, increase water temperature, and create potential for fish entrapment 

(Langer 2003; NMFS 2004). A reduction in groundwater elevation may occur when 

floodplain pits are pumped by operators to increase production, and by evaporation of 
 

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surface water in large pits. Reductions in groundwater elevations can consequently result in a 

decrease in stream flow, which is particularly hazardous to fish during low flow periods. 

Subsurface connectivity between pits and streams also presents a possibility of increased 

stream temperatures when pit surface water is heated by the sun and eventually drains to the 

stream. The risk of fish entrapment associated with floodplain pit mining is due to two 

processes: (1) floods overtopping the pit perimeter, and (2) natural migration of the channel 

into the excavated area (Kondolf 1998a). Ponded water isolated from the main channel may 

strand or entrap fish carried there during high water events (Moulton 1980; Palmisano et al. 

1993; Kondolf 1997). Fish in these ponded areas could experience higher temperatures, 

lower dissolved oxygen, increased predation compared to fish in the main channel, an altered 

food web, desiccation if the area dries out, and freezing (Moulton 1980; Spence et al. 1996; 

Kondolf 1997, 1998a).

The likelihood and extent of groundwater, stream flow, water temperature, and entrapment 

effects associated with floodplain mining are directly related to the pit’s proximity to the 

active stream channel, pit size relative to the stream, and the frequency of flood inundation 

(Langer 2003; NMFS 2004). 

9. Destruction of the riparian zone during gravel extraction operations can have multiple 

deleterious effects on anadromous fish habitat. The importance of riparian habitat to 

anadromous fishes (Koski 1993) should not be underestimated. For example, Koski (1992) 

states that a stream’s capacity to produce salmonids is controlled by the structure and 

function of the riparian zone. The riparian zone includes stream banks, riparian vegetation, 

and vegetative cover. Damaging any one of these elements can cause stream bank 

destabilization resulting in increased erosion, sediment and nutrient inputs, and reduced 

shading and bank cover leading to increased stream temperatures. Destruction of riparian 

trees also means a decrease in the supply of large woody debris. This results in a loss of 

instream habitat diversity caused by removing the source of materials partially responsible 

for creating pools and riffles that are critical for anadromous fish growth and survival, as 

outlined in Environmental Effect Number 7, above (Koski 1992; Murphy 1995; OWRRI 

1995).

Gravel extraction activities can damage the riparian zone in several ways: 

$ If the floodplain aquifer discharges into the stream, groundwater levels can be lowered 

because of channel degradation. Lowering the water table can kill riparian vegetation 

(Collins and Dunne 1990). 

$ Long-term loss of riparian vegetation can occur when gravel is removed to depths that 

result in permanent flooding or ponded water. Also, loss of vegetation occurs when 

gravel removal results in a significant shift of the river channel that subsequently causes 

annual or frequent flooding into the disturbed site (Joyce 1980). 

$ Heavy equipment, processing plants, and gravel stockpiles at or near the extraction site 

can destroy riparian vegetation (Joyce 1980; Kondolf 1994a; OWRRI 1995). Heavy 

equipment also causes soil compaction, thereby increasing erosion by reducing soil 

infiltration and causing overland flow. As mentioned in Environmental Effect Number 5 

above, the use of heavy equipment also leads to the increased risk of chemical pollution; 
 

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hazardous chemicals may also be used in nearby sediment processing plants. In addition, 

roads, road building, road dirt and dust, and temporary bridges can also impact the 

riparian zone. 

$ Removal of large woody debris from the riparian zone during gravel extraction activities 

negatively affects the plant community (Weigand 1991; OWRRI 1995). Large woody 

debris is important in protecting and enhancing recovering vegetation in streamside areas 

(Franklin et al. 1995; OWRRI 1995). 

$ Rapid bed degradation may induce bank collapse and erosion by undercutting and by 

increasing the heights of banks (Collins and Dunne 1990; Kondolf 1994a, 1997). 

$ Portions of incised or undercut banks may be removed during gravel extraction, resulting 

in reduced vegetative bank cover, causing reduced shading and increased water 

temperatures (Moulton 1980). 

$ Banks may be scraped to remove overburden to reach the gravel below. This may result 

in destabilized banks and increased sediment inputs (Moulton 1980). 

$ The reduction in size or height of bars can cause adjacent banks to erode more rapidly or 

to stabilize, depending on how much gravel is removed, the distribution of removal, and 

the geometry of the particular bed (Collins and Dunne 1990). 

10. Gravel mining can cause a change in disturbance regimes and patterns with a 

concomitant change in habitat and species (Castro and Cluer, unpublished report). Stream 

and river systems are disturbance driven, which can temporarily or permanently alter the 

character of the system. These disturbances include natural variations in flow regimes and 

flood events, sediment delivery to the system, large inputs of organic materials, changes in 

base level, etc. Disturbances can be described by their frequency (e.g., the 100-year flood), 

duration (length of time), magnitude (areal extent), intensity (force exerted), and severity 

(biological response) (OWRRI 1995). The bed within the active stream channel experiences 

the greatest disturbance frequency, which could be as often as every year (i.e., sediment 

transport events). The side channel and backwater areas are not as frequently disturbed, but 

are affected by higher flow events and channel avulsions (perhaps 5- to 10-year flows). 

Floodplains are disturbed even less frequently than the main and side channels; it may take a 

major flood event on the order of a decade or longer before the floodplain shows significant 

alteration. Finally, terraces and hillslopes have the lowest disturbance frequency (e.g., slope 

failures and mass movements). 

Common to all these disturbances is that the episode of disturbance is followed by a period 

of recovery (OWRRI 1995). If the disturbance events become so frequent that the system 

cannot fully recover before the next event, then the system is held in a constant state of 

disequilibrium or instability (Castro and Cluer, unpublished report). Organisms in these 

habitats show different responses to these disturbances, depending on such factors as their 

differences in developmental times, behavior, and their responses to environmental factors 

(OWRRI 1995). Pringle (1997) contends that anthropogenic activities downstream, including 

urbanization, dams, gravel mining, etc., can cause effects on organisms upstream, such as 

genetic isolation, population-level changes, and ecosystem-level changes. Alteration of a 

punctuated disturbance regime (as described above) to one of chronic disturbance overlain 

with larger infrequent disturbances often results in a shift of the plant and animal 

communities to ones that are more adapted to constant disturbance (OWRRI 1995). Incised 
 

9 

streams and rivers may be subject to chronic disturbance because of the disconnection of the 

floodplain. Instream gravel mining may cause chronic disturbance with a concomitant 

change in the habitat and associated species. Although sediment transport events may occur 

annually, and may be compared to gravel mining activities, the latter are temporally distinct 

from natural events. As OWRRI (1995) affirms about salmonids:

Over the last six million years salmonids have evolved within the natural 

disturbance regime. Novel disturbances can shift the ecological rules governing 

community structure making the recovery of the original biota impossible. 

IV. RECOMMENDATIONS

The following recommendations do not specify the measures, if any, that would need to be 

implemented by parties engaged in gravel extraction activities in order to comply with applicable 

statutory requirements. In formulating its recommendations or prescriptions, NMFS will 

determine the acceptable means of demonstrating compliance with statutory requirements based 

on information available to the agency, as appropriate under the circumstances presented. As 

such, the language of this Guidance should not be read to establish any binding requirements on 

agency staff or the regulated community. The recommendations should not be regarded as static 

or inflexible, and are meant to be revised as the science upon which they are based improves and 

areas of uncertainty are resolved. Furthermore, the recommendations are meant to be modified 

for regional or local use, so a degree of flexibility in their interpretation and application is 

essential. 

In general terms, gravel extraction operations located in or immediately adjacent to streams have 

greater impacts to anadromous fish resources and habitats than operations located farther from 

the stream. Therefore, NMFS recommends that all reasonable efforts be made to identify 

gravel sources in upland areas and terraces before deciding to site project operations in or 

near streams. This is commensurate with the CWA section 404 rationale of avoiding impacts, 

minimizing (when not reasonably possible to avoid), and then mitigating (when not reasonably 

possible to minimize). 

If, after a thorough alternatives analysis, instream, floodplain, or terrace mining is going to 

proceed, NMFS recommends that project operations be carefully designed to minimize impacts 

to trust resources, including habitat. If the recommendations outlined in this Guidance are 

followed, such that (1) anadromous fishes and their habitats are protected and (2) appropriate 

and timely restoration is implemented to mitigate unavoidable impacts, gravel mining can, as 

suggested by Langer (2003), take place within acceptable limits. Many factors must be 

considered when designing a gravel mining project that conforms to environmental constraints. 

The recommendations below present only a general list of these considerations. Each project 

should be considered in its own context, based on project design, stream type and condition, 

natural resources, and cumulative impacts. NMFS Regional Offices are encouraged to adopt 

more detailed guidelines tailored to specific physical settings and biological needs. 
 

10 

1. NMFS recommends that upland aggregate sources, terraces and inactive floodplains be 

used preferentially to active channels, their deltas and floodplains. It is recommended 

that gravel extraction sites be situated outside the active floodplain and that the gravel not be 

excavated from below the water table. In other words, dry-pit mining on upland outcrops, 

terraces, or the floodplain is preferable to any of the instream alternatives. Bar skimming is 

generally preferable to wet-pit mining (deep water dredging) within the active channels if no 

upland or floodplain sources are reasonably available (see Recommendation Number 6, 

below). In addition, it is recommended that operators not divert streams to create an inactive 

channel for gravel extraction purposes, and avoid the formation of isolated ponded areas that 

cause fish entrapment. In all cases, it is recommended that efforts be made to minimize the 

need for crossing active channels with heavy equipment. 

2. NMFS recommends that pit excavations located on the adjacent floodplain or terraces 

should be preferentially sited outside the channel migration zone, and as far from the 

stream as possible. NMFS recommends that pits be separated from the active channel 

by a buffer designed to maintain this separation for several decades. As previously 

discussed in Section II, the effects of floodplain mining are related to the subsurface 

hydrological connections between pits and streams, as well as the potential for active channel 

migration into the floodplain pits (“pit capture”). Therefore, as noted by Kondolf (1993, 

1994a), NMFS recommends that pits be considered as potentially instream when viewed on a 

time scale of decades. Consequently, it is recommended that floodplain pits be located 

outside the channel migration zone and as far from the stream as possible. This is particularly 

important given that the likelihood and extent of adverse effects associated with floodplain 

mining is directly related to the pit’s proximity to the active channel (Langer 2003; NMFS 

2004). It is recommended that buffers or levees that separate the pits from the active channel 

be sufficient to accommodate long-term channel migration, infrequent flooding, or 

inundation; and to avoid fish entrapment. Kondolf (1997) reminds us that: 

A river channel and floodplain are dynamic features that constitute a single 

hydrologic and geomorphic unit characterized by frequent transfers of water and 

sediment between the two components. The failure to appreciate the integral 

connection between floodplain and channel underlies many environmental 

problems in river management today. 

Generally, the physical setback of the pit from the channel should be based on 

several channel widths, or on the meander belt. Pit size should also be considered 

in determining appropriate buffers. Larger pits have the capacity to absorb a much 

greater volume of sediment than smaller pits, upon pit capture. 

3. NMFS recommends that larger rivers and streams be used preferentially to small rivers 

and streams. Larger systems generally have more gravel and a wider floodplain, and a 

proportionally smaller disturbance in large systems will reduce the overall impact of gravel 

extraction (Follman 1980). On a smaller river or stream, the location of the extraction site is 

more critical because of the limited availability of exposed gravel deposits and the relatively 

narrower floodplain (Follman 1980). In either case, NMFS recommends that the extraction 

volume relative to coarse sediment load be low.
 

11 

4. NMFS recommends that braided river systems be used preferentially to other river 

systems. The river systems, listed in the order of increasing sensitivity to physical changes 

caused by gravel extraction activities, are: braided, split, meandering, sinuous, and straight 

(Rundquist 1980). Because braided river systems are dynamic and channel shifting may be a 

frequent occurrence, channel shifting resulting from gravel extraction might have less overall 

impact because it is analogous to a naturally occurring process (Follman 1980). However, 

gravel extraction from braided streams is still considered instream extraction, and NMFS 

recommends that it be avoided. 

5. NMFS recommends that instream gravel removal quantities be strictly limited so that 

gravel recruitment and accumulation rates are sufficient to avoid prolonged impacts on 

channel morphology and anadromous fish habitat. While this is conceptually simple, 

annual gravel recruitment to a particular site is, in fact, highly variable and not well 

understood. Recruitment is the rate at which bedload is supplied from upstream to replace the 

extracted material. Kondolf (1993, 1994b) dismisses the common belief that instream gravel 

extraction can be conducted safely as long as the rate of extraction does not exceed the rate 

of replenishment. Kondolf (1993, 1994b) states that this approach to managing instream 

gravel extraction is flawed because it fails to account for the upstream/downstream erosional 

effects that change the channel morphology as soon as gravel extraction begins. In addition, 

Kondolf (1993, 1994b, 1997) reiterates that flow and sediment transport for most rivers and 

streams is highly variable from year to year, thus an annual average rate may be meaningless. 

An “annual average deposition rate” could bear little relation to the sediment transport 

regimes in a river in any given year. Moreover, sediment transport processes are very 

difficult to measure and to model, so estimates of bedload transport may prove unreliable 

(Kondolf 1997). These problems and uncertainties indicate a need for cautious interpretation 

of sediment yield results, and the conservative application of volume limitations on 

extraction projects. Any gravel removal in streams or rivers that have a recent history of 

eroding bars or banks and/or stream bed lowering is not recommended. 

Collins and Dunne (1990) recommend that appropriate rates and locations for instream 

gravel extraction should be determined on the basis of: 

• the rate of upstream recruitment; 

• whether the river bed elevation under undisturbed conditions remains the same over the 

course of decades, or the rate at which it is aggrading or degrading; 

• historic patterns of sediment transport, bar growth, and bank erosion; 

• prediction of the specific, local effects of gravel extraction on bed elevations, and the 

stability of banks and bars, taking into account an analysis of present or past effects of 

gravel extraction at various rates; and 

• a determination of the desirability or acceptability of the anticipated effects. 

In addition, it is recommended that the habitat values of remaining (or newly recruited) 

sediments be functionally adequate or equivalent for the purposes of migration, spawning, 

rearing, benthic invertebrate production, and any other identified habitat needs. Upstream 

recruitment is ineffective if the necessary ecological functions are not replaced or restored. 
 

12 

6. NMFS recommends that gravel bar skimming be allowed only under restricted 

conditions. (See Section III, Environmental Effect Number 4, for the environmental impacts 

of gravel bar skimming.) Therefore, NMFS recommends that: 

• gravel be removed only during low flows and from strictly defined areas above the lowflow water level; 

• berms and buffer strips be used to direct stream flow away from the site and to provide 

for continued migratory habitat; 

• the final grading of the gravel bar not significantly alter the flow characteristics of the 

river during periods of high flows (OWRRI 1995); 

• bar skimming operations be monitored to ensure they are not adversely affecting gravel 

recruitment or channel morphology either upstream or downstream from the site; 

• geomorphic features be monitored using methods that quantify their physical dimensions 

and changes at appropriate time scales. This will likely include densely spaced cross 

sections to cover the geomorphic features, topographic mapping techniques that do not 

rely solely on cross sections but follow terrain features, and modern mapping techniques 

that grid entire areas with closely spaced data; and 

• any gravel removal in streams or rivers that have a recent history of eroding bars or 

banks, or stream bed lowering, be discouraged. 

7. NMFS recommends that, prior to gravel removal, a thorough review of sediments and 

point and non-point sources of contaminants be conducted. Toxic compounds from a 

variety of sources (municipalities, manufacturing plants, hardrock mines, etc.) may be 

present in sediments, and can be released into the stream when disturbed during gravel 

extraction operations. It is recommended that sediment testing be conducted to detect metals 

and organic compounds (DDT, PCBs, etc.), and residual acid or heavy metal drainage from 

hardrock mining operations; and that during project operations, extracted gravel, sand, and 

sediments not be washed directly in the stream or river or within the riparian zone. 

In addition, it is recommended that an assessment of contaminant sources be completed to 

assist in determining potential problems with contaminated sediments. Sources can include 

farming, mining, National Pollutant Discharge Elimination System (NPDES)-permitted 

activities, forestry, sewage treatment plants, and other municipal infrastructure. 

To minimize the suspension of sediments, it is recommended that measures be taken to 

contain turbidity plumes, and to avoid excessive disturbance of sediments. It is also 

recommended that turbidity levels do not exceed maximum allowable turbidity limits for 

anadromous fish and their prey. 

8. NMFS recommends that removal or disturbance of instream roughness elements 

during gravel extraction activities be avoided, and that those that are disturbed be 

replaced or restored. As previously stated in Section III, Environmental Effect Number 7, 

instream roughness elements, particularly large woody debris, are critical to stream and river 

ecosystem functioning. This may be particularly true in small streams where large woody 
 

13 

debris plays a relatively greater role in channel morphology and sediment dynamics than it 

does in larger streams or rivers. In addition, it is recommended that gravel itself be 

considered an instream roughness element, and that consideration be given to leaving 

similar-sized gravel in the stream bed, in addition to replacing large woody debris. 

9. NMFS recommends that gravel extraction operations be managed to avoid or minimize 

damage to stream/river banks and riparian habitats. Therefore, NMFS recommends that: 

• gravel extraction in vegetated (or those that would be vegetated without repeated 

anthropogenic disturbances) and riparian areas be avoided; 

• gravel pits located on the adjacent floodplain not be excavated below the water table; 

• berms and buffer strips in the floodplain that keep active channels in their original 

locations or configurations be maintained for several decades (as in Recommendation 

Number 2, above); 

• undercut and incised vegetated banks not be altered; 

• large woody debris in the riparian zone be left undisturbed or replaced when moved; 

• all support and processing operations (e.g., gravel washing) be done outside the riparian 

zone; 

• gravel stockpiles, overburden and/or vegetative debris not be stored within the riparian 

zone, and they be disposed of properly after extraction; 

• operation and storage of heavy equipment within riparian habitat be restricted; 

• access roads not encroach into the riparian zones; and 

• riparian zone protection extend well upstream and downstream from the project site when 

possible because the erosional effects of instream gravel mining can be manifested miles 

upstream and downstream from the site of operations. 

10. NMFS recommends that the cumulative impacts of gravel extraction operations to 

anadromous fishes and their habitats be addressed by the Federal, state, and local 

resource management and permitting agencies and be considered in the permitting 

process. The cumulative impacts on anadromous fish habitat caused by multiple extractions 

and sites in a given stream, river, or watershed are compounded by other riverine impacts 

and land use disturbances in the watershed. These additional impacts may be caused by river 

diversions/impoundments, flood control projects, logging, grazing, and channel/riparian 

encroachment. The technical methods for assessing, managing, and monitoring cumulative 

effects are a future need outside the scope of this Gravel Guidance document. Nevertheless, 

it is recommended that individual gravel extraction operations be judged from a perspective 

that includes their potential adverse cumulative impacts (Kondolf 1997, 1998a; see also 

Council on Environmental Quality 1997 and U.S. EPA, Office of Federal Activities 1999 for 

general cumulative impact guidance). It is recommended that this be reflected in any gravel 

extraction management plan. NMFS will promote the same watershed approach to 

cumulative impact analysis when reviewing non-mining activities in or near the aquatic 

environment. 
 

14 

11. NMFS recommends that an integrated environmental assessment, management, and 

monitoring program be a part of any gravel extraction operation, and encouraged at 

Federal, state, and local levels. Assessment is used to predict possible environmental 

impacts. Management is used to implement plans to prevent, minimize, and mitigate negative 

impacts. Monitoring is used to determine if the assessments were correct, to detect 

environmental changes, and to support management decisions.

Before gravel mining operations commence, it is recommended that operators submit plans 

to the appropriate Federal, state and local agencies outlining their proposed project, including 

but not limited to location, methods, timing, duration, proposed extraction volumes, and 

post-mining landscape morphology. Prior to extraction, it is important to establish existing 

biological and physical conditions, evaluate possible environmental impacts, and describe 

ways in which adverse environmental impacts are to be prevented or minimized, with the 

goal of achieving and maintaining the natural ecological functions of the habitat. Using a 

combination of best available technologies and methods, it is recommended that the 

following be assessed: 

• Characterize and identify fish species distributions, abundances, and life stages. 

• Identify habitat requirements and determine limiting environmental factors of the 

anadromous fish populations. In addition to the limiting factors identified by Koski 

(1992), it is recommended that this analysis evaluate the proposed timing of extraction 

operations relative to adult and juvenile migration patterns and choose in-water work 

windows accordingly. 

• Develop a flow frequency curve. 

• Calculate sediment budgets, taking into consideration such periodic natural events as 

floods (Meador and Layher 1998). 

• Predict possible changes in water quality, channel morphology, and potential adverse 

cumulative impacts. 

• Propose a mitigation and restoration strategy based on preventing impacts, minimizing 

unavoidable impacts, and mitigating for all immediate and cumulative impacts (see 

Recommendation Number 12, below). 

NMFS recommends that the operators also check with their NMFS Regional Offices for any 

regionally specific procedures and guidelines. 

While gravel mining operations are ongoing, it is important to monitor permitted operations 

and verify environmental safeguards. At a minimum, it is recommended that the following 

attributes be monitored on a regular basis: 

• extraction rates and volumes; 

• impacts to the river bed, banks, and bars adjacent to, upstream, and downstream of the 

project using benchmarked channel cross sections, Digital Elevation Models, and aerial 

photographs; 

• species distributions and abundances; 

• water quality, including turbidity, dissolved oxygen and contaminants; and 

• effectiveness of mitigation activities. 
 

15 

NMFS recommends that permits have a maximum 5-year limit and be subject to annual 

review and revision to protect anadromous fish and their habitats (e.g., it is recommended 

that one element of the annual review determine whether resource management and 

monitoring objectives are being met). NMFS recommends that a third party be responsible 

for carrying out monitoring activities and reporting these results to the permitting agency, the 

operator, the appropriate natural resource agencies, and other stakeholders.

12. NMFS recommends that mitigation be an integral part of the management of gravel 

extraction projects. It is important that mitigation be based on replacing equivalent habitat 

values and functions, as per the U.S. Army Corps of Engineers (USACE) Regulatory 

Guidance Letter No. 02-2 (2002) on compensatory mitigation. It is recommended that a 

mitigation strategy be included in the management program of each project, and, where 

possible, mitigation activities be initiated concurrently with the gravel mining operations. 

NMFS recommends that a mechanism for correcting problems identified via monitoring be 

written into the permit, as monitoring is not worthwhile unless there is a mechanism to 

address problems that are identified as a result of the monitoring program. In terms of 

National Environmental Policy Act (NEPA) regulations, mitigation includes, in sequential 

order: 

• avoidance of direct or indirect impacts or losses;

• minimization of the extent or magnitude of the action;

• repair, rehabilitation or restoration of integrity and function;

• reduction or elimination of impacts by preservation and maintenance; and 

• compensation by replacement or substitution of the resource or environment.

Thus, restoration follows avoidance and minimization. The preceding definitions 

recommend that restoration aim to restore the biotic integrity of a riverine ecosystem, not just 

repair the damaged abiotic components. An overview of river and stream restoration can be 

found in Gore et al. (1995). A universal, prototype long-term monitoring strategy for 

watershed and stream restoration can be found in Bryant (1995); see also the various papers 

by Kondolf and others (e.g., Kondolf and Larson 1995; Kondolf and Micheli 1995; Kondolf 

1998b). In addition, see Beechie and Bolton (1999), who discuss approaches to restoring 

salmonid habitat-forming processes in Pacific Northwest watersheds, and Roni et al. (2002), 

who review stream restoration techniques and present a hierarchical strategy for prioritizing 

restoration in these watersheds. 

Koski (1992) states that the concept of stream habitat restoration as applied to anadromous 

fishes is based on the premise that fish production increases when those environmental 

factors that limit production are alleviated. Thus, an analysis of those “limiting factors” is 

critical to the restoration process. Koski (1992) further states that effective stream habitat 

restoration must be holistic in scope, and approached through a three-step process:

1. First, a program of watershed management and restoration must be applied to 

the watershed to ensure that all major environmental impacts affecting the entire 

stream ecosystem are addressed (i.e., cumulative impacts). Obviously, an 

individual gravel extraction project is not expected to restore an entire watershed 
 

16 

suffering from cumulative effects for which it was not responsible. Rather, needed 

mitigation and restoration activities in a riverine system should focus on direct 

and indirect project effects and must be designed within the context of overall 

watershed management. 

2. Next, restore the physical structure of the channel, instream habitats, and 

riparian zones (e.g., stabilize stream banks through replanting of riparian 

vegetation, conserve spawning gravel, and replace large woody debris). This 

would reestablish the ecological carrying capacity of the habitat. 

3. Finally, the fish themselves should be managed to ensure that there are 

sufficient spawning populations for maximizing the restored carrying capacity of 

the habitat. 

Without restoration, stream recovery from gravel mining can take decades (Kanehl and 

Lyons 1992). However, NMFS recommends that reliance on restoration be put into proper 

perspective. It is important to acknowledge that there are significant gaps in our 

understanding of the methodology and effectiveness of restoration of streams and 

anadromous fish habitat affected by gravel extraction activities. Overall, restoration as a 

science is relatively young and experimental, and the processes and mechanisms are poorly 

understood. Little is known about the functional value, stability and resiliency of many socalled “restored” habitats. To date, existing regulations or plans pertaining to the mitigation 

and restoration of gravel extraction sites have been simplistic or vague, and, because 

restoration science and planning is still rudimentary, NMFS recommends that each project 

first begin its mitigation analysis with avoidance and minimization. 

As an example, gravel extraction in California is regulated under the concept of 

“reclamation,” which is derived from open-pit surface mining, such as large coal mines. 

Although the definition and implementation of reclamation may vary among states, Kondolf 

(1993, 1994b) states the concept of reclamation, as applied to open-pit mines, often assumes 

that the environmental impacts are confined to the site; therefore, site treatment is considered 

in isolation from changes in the surrounding terrain. Kondolf (1993, 1994b) suggests that this 

definition treats the site as an essentially static feature of the landscape. He argues that, while 

these assumptions may work for extraction operations located in inactive stream or river 

terraces, active channels and floodplains are dynamic environments, where disturbances can 

spread rapidly upstream and downstream from the site during and after the time of operation. 

The stream or river will irrevocably readjust its profile during subsequent high flows, 

eradicating the gravel pits and giving the illusion that extraction has had no impact on the 

channel. Kondolf (1993, 1994b) claims that a survey of bed elevations will show a net 

lowering of the bed, which reflects the more even distribution of downcutting (erosion) along 

the length of the channel. Even if the channel profile were to recover after project completion 

due to an influx of fresh sediment from upstream, habitat will have been lost in the 

meantime. Thus, it is not possible to disturb one site in isolation from the rest of the 

ecosystem, or confine the disturbance to a single, detached location, and then subsequently 

reclaim or reverse the impacts (Brown et al. 1998). Kondolf (1993, 1994b) concludes that 

reclamation can be applied to gravel pits in terrace deposits above the water table, but the 

reclamation concept is not workable for regulating instream gravel extraction. Similarly, 
 

17 

regarding instream gravel mining, Brown et al. (1998) conclude that “total restoration of 

severely affected streams would probably be impossible.” 

Moreover, Kondolf (1998a) reminds us that: 

The effects of instream gravel mining may not be obvious immediately because 

active sediment transport is required for the effects (e.g. incision, instability) to 

propagate upstream and downstream. Given that geomorphically-effective 

sediment transport events are infrequent on many rivers, there may be a lag of 

several or many years before the effects of instream gravel mining are evident and 

propagate along the channel. Thus, gravel mines may operate for years without 

apparent effects upstream or downstream, only to have the geomorphic effects 

manifest years later during high flows. Similarly, rivers are often said to have 

“long memories,” meaning that the channel adjustments to instream extraction or 

comparable perturbations may persist long after the activity itself has ceased. 

This delayed manifestation of geomorphic effects leads to the false assumption that floods 

cause damage to stream systems, when in actuality anthropogenic changes often “set the 

stage” for geomorphic change. Large flood events simply provide the necessary stream 

power for the changes to occur. 

For further guidance on mitigation, refer to the USACE Regulatory Guidance Letter 

(USACE 2002) noted above and the joint guidance on the Use of In-Lieu-Fee Arrangements 

for Compensatory Mitigation Under Section 404 of the Clean Water Act and Section 10 of 

the Rivers and Harbors Act (65FR 66913, November 7, 2000). 

13. NMFS recommends that gravel extraction projects proposed as stream restoration 

activities be regarded with caution. Resource management agencies acknowledge that, 

under the right circumstances, some gravel extraction projects, whether commercial or 

performed by the agencies themselves, may offer important opportunities for anadromous 

fish habitat enhancement. That is, gravel removal itself can be used beneficially as a tool for 

habitat creation, restoration, or rehabilitation (OWRRI 1995). While it is tempting to 

promote gravel extraction as a means to enhance or restore stream habitat, the underlying 

objective of this Guidance document is to prevent adverse impacts caused by commercial 

gravel extraction operations. Therefore, NMFS recommends that gravel extraction for habitat 

enhancement purposes, done in conjunction with commercial gravel operations, not take 

precedence over, and not be a substitute for, habitat protection. It is recommended that any 

proposals to perform gravel extraction for habitat enhancement purposes be done in 

consultation with NMFS regional field offices and technical experts. 

NMFS recommends that either a mitigation fund, with contributions paid by the operators, or 

royalties from gravel extraction be used to fund mitigation programs and to perform 

effectiveness monitoring. A possible use of mitigation funds and royalties could include 

conducting studies to further the knowledge of extraction impacts in a given watershed. Such 

studies might include: a review of historical impacts; identification of alternative aggregate 

sources; a watershed-based evaluation of mitigation alternatives; identification of sites where 
 

18 

it is recommended that extraction activities be avoided; and recommended removal 

thresholds. 

In light of the dynamic, unpredictable, and episodic nature of stream hydrology and sediment 

transport, NMFS cautions against relying too heavily on restoration, and agrees with both 

Murphy (1995) and Langer (2001) that the best form of habitat mitigation is to avoid or 

minimize adverse impacts to the environment.
 

19 

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23 

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25 

APPENDIX 1

SUMMARIES OF MAJOR STATUTES

The following summaries of the major statutes mentioned in this Gravel Guidance document, 

with the exception of the Rivers and Harbors Act of 1899, are based on Buck (1995)1

. 

Clean Water Act

The Clean Water Act (CWA) (33 U.S.C. 1251-1387) is a very broad statute with the goal of 

maintaining and restoring waters of the United States. The CWA authorizes water quality and 

pollution research; provides grants for sewage treatment facilities; sets pollution discharge and 

water quality standards; addresses oil and hazardous substances liability; and establishes permit 

programs for water quality, point source pollutant discharges, ocean pollution discharges, and 

dredging or filling of wetlands. The intent of the CWA Section 404 program and its 404(b)(1) 

Guidelines is to prevent destruction of aquatic ecosystems, including wetlands, unless the action 

will not individually or cumulatively adversely affect the ecosystem. The National Marine 

Fisheries Service (NMFS) can provide comments to the U.S. Army Corps of Engineers 

(USACE) as to the impacts to living marine resources of proposed activities and can recommend 

methods for avoiding such impacts. 

If NMFS determines that a proposed action will result in “substantial and unacceptable adverse 

impacts on aquatic resources of national importance,” the Assistant Secretary for Oceans and 

Atmosphere may request that the decision be reviewed at a higher level in the USACE. A 

404(q) elevation pauses the permit process for about 2 months while the two departments 

exchange information to address concerns about the proposed project. Although outright permit 

denials are rare, there are often modifications to the project proposal resulting in a less harmful 

action. 

Endangered Species Act

The purpose of the 1973 Endangered Species Act (ESA) (16 U.S.C. 1531-1543) is to provide a 

means whereby the ecosystems upon which endangered or threatened species depend may be 

conserved, and to provide a program for the conservation of such endangered and threatened 

species. If a Federal action may affect ESA-listed species or their critical habitat, the action 

agency must initiate consultation with NMFS under section 7 of the ESA. Other pertinent 

sections of the ESA include section 9 (direct take) and section 10 (exemptions from take 

prohibitions). 

 

1

Buck, E.H. 1995. Summaries of major laws implemented by the National Marine Fisheries Service. CRS Report for 

Congress. Congressional Research Service, Library of Congress, March 24, 1995. 
 

26 

Fish and Wildlife Coordination Act

The Fish and Wildlife Coordination Act (FWCA) (16 U.S.C. 661-666c) requires that wildlife, 

including fish, receive equal consideration and be coordinated with other aspects of water 

resource development. This is accomplished by requiring consultation with the U.S. Fish and 

Wildlife Service, NMFS and appropriate state agencies whenever any body of water is proposed 

to be modified in any way and a Federal permit or license is required. These agencies determine: 

(1) the possible harm to fish and wildlife resources; (2) the measures needed to both prevent the 

damage to and loss of these resources; and (3) the measures needed to develop and improve the 

resources, in connection with water resource development. NMFS submits comments to Federal 

licensing and permitting agencies on the potential harm to living marine resources caused by the 

proposed water development project, and provides recommendations to prevent harm. 

Magnuson-Stevens Fishery Conservation and Management Act 

The Magnuson-Stevens Fishery Conservation and Management Act, first passed in 1976 and 

amended in 1996, is the primary legislation governing marine fisheries in the United States. 

This legislation established eight Regional Fishery Management Councils to manage fishery 

resources in the Exclusive Economic Zone under Fishery Management Plans (FMPs) for 

Federally managed fisheries. Plans may include one or several species and are designed to 

achieve specified management goals for a fishery. 

The 1996 reauthorization of the Magnuson-Stevens Act included a provision for Essential Fish 

Habitat (EFH). The act states: “One of the greatest long-term threats to the viability of 

commercial and recreational fisheries is the continuing loss of marine, estuarine, and other 

aquatic habitats. Habitat considerations should receive increased attention for the conservation 

and management of fishery resources of the United States” (16 U.S.C. 1801 (A)(9)). The 

definition of EFH in the legislation covers “those waters and substrate necessary to fish for 

spawning, breeding, feeding, or growth to maturity.” The legislation mandates that NMFS and 

the Councils implement a process for conserving and protecting EFH. Key features of this 

process are: 

1. Designate EFH. Councils are required to describe and identify EFH for each life stage of the 

species included in their FMPs. 

2. Minimize to the extent practicable the adverse effects of fishing on EFH. Councils must 

assess fishing impacts to EFH, taking Habitat Areas of Particular Concern (HAPCs) into 

special consideration (i.e., habitat types that are especially sensitive, ecologically important, 

or rare), and minimize the impacts of fishing on EFH to the extent practicable. 

3. Consult on potential fishing and non-fishing impacts to EFH. NMFS and the Councils are 

required to comment on activities proposed by Federal action agencies (e.g., U.S. Army 

Corps of Engineers, Federal Energy Regulatory Commission, and Department of the Navy) 

that may adversely impact areas designated as EFH. 

4. Further review of decisions inconsistent with NMFS or Council recommendations. If a 

Federal agency decision is inconsistent with a NMFS conservation recommendation, the 
 

27 

Assistant Administrator for Fisheries may request a meeting with the head of the Federal 

action agency to review and discuss the issue. 

National Environmental Policy Act

The National Environmental Policy Act (NEPA) (42 U.S.C. 4321-4347) requires Federal 

agencies to analyze the potential effects of a proposed Federal action that would significantly 

affect the human environment. It specifically requires agencies to use a systematic, 

interdisciplinary approach in planning and decision making to ensure that presently unquantified 

environmental values may be given appropriate consideration and to provide detailed statements 

on the environmental impacts of proposed actions, including (1) any adverse impacts, (2) 

alternatives to the proposed action, and (3) the relationship between short-term uses and longterm productivity. The agencies use the results of this analysis in decision making. Alternatives 

analysis allows other options to be considered. NMFS plays a significant role in the 

implementation of NEPA through its consultative functions relating to conservation of marine 

resource habitats. 

Rivers and Harbors Act of 1899

The Rivers and Harbors Act of 1899, Section 10 (33 U.S.C. 403), authorizes the USACE to 

regulate activities that affect waters of the United States. These activities include construction of 

wharves, piers and jetties and excavating or altering stream channels of navigable waters. NMFS 

may comment on proposed activities (usually via the FWCA), and the CWA 404(q) elevation 

process (see Clean Water Act, above) is available to NMFS under the Rivers and Harbors Act.