|
Habitat
Parameter |
Condition Category |
|
Optimal |
Suboptimal |
Marginal |
Poor |
|
1. Epifaunal Substrate/Available Cover |
Greater than 70% of substrate favorable for epifaunal colonization and fish cover; mix of snags, submerged logs, undercut banks, cobble or other stable habitat and at stage to allow full colonization potential (i.e., logs/snags that are not new fall and not transient). |
40-70% mix of stable habitat; well suited for full colonization potential; adequate habitat for maintenance of populations; presence of additional substrate in the form of newfall, but not yet prepared for colonization (may rate at high end of scale). |
20-40% mix of stable habitat; habitat availability less than desirable; substrate frequently disturbed or removed. |
Less than 20% stable habitat; lack of habitat is obvious; substrate unstable or lacking. |
|
SCORE |
20 19 18 17 16 |
15 14 13 12 11 |
10 9 8 7 6 |
5 4 3 2 1 0 |
|
2. Embeddedness |
Gravel, cobble, and boulder particles are 0-25% surrounded by fine sediment. |
Gravel, cobble, and boulder particles are 25-50% surrounded by fine sediment. |
Gravel, cobble, and boulder particles are 50-75% surrounded by fine sediment. |
Gravel, cobble, and boulder particles are more than 75% surrounded by fine sediment. |
|
SCORE |
20 19 18 17 16 |
15 14 13 12 11 |
10 9 8 7 6 |
5 4 3 2 1 0 |
|
3. Velocity / Depth Regime |
All 4 velocity/depth regimes present (slow-deep, slow-shallow, fast-deep, fast-shallow). (slow is <0.3 m/s, deep is >0.5m) |
Only 3 of the 4 regimes present (if fast-shallow is missing, score lower than if missing other regimes). |
Only 2 of the 4 habitat regimes present (if fast-shallow or slow-shallow are missing, score low). |
Dominated by 1 velocity/depth regime (usually slow-deep). |
|
SCORE |
20 19 18 17 16 |
15 14 13 12 11 |
10 9 8 7 6 |
5 4 3 2 1 0 |
|
4. Sediment Deposition |
Little or no enlargement of islands or point bars and less than 5% (<20% for low-gradient streams) of the bottom affected by sediment deposition. |
Some new increase in bar formation, mostly from gravel, sand or fine sediment; 5-30% (20-50% for low-gradient) of the bottom affected; slight deposition in pools. |
Moderate deposition of new gravel, sand or fine sediment on old and new bars; 30-50% (50-80% for low-gradient) of the bottom affected; sediment deposits at obstructions, constrictions, and bends; moderate deposition of pools prevalent. |
Heavy deposits of fine material, increased bar development; more than 50% (80% for low-gradient) of the bottom changing frequently; pools almost absent due to substantial sediment deposition. |
|
SCORE |
20 19 18 17 16 |
15 14 13 12 11 |
10 9 8 7 6 |
5 4 3 2 1 0 |
|
5. Channel Flow Status
|
Water reaches base of both lower banks, and minimal amount of channel substrate is exposed. |
Water fills >75% of the available channel; or <25% of channel substrate is exposed. |
Water fills 25-75% of the available channel, and/or riffle substrates are mostly exposed. |
Very little water in channel and mostly present as standing pools. |
|
SCORE |
20 19 18 17 16 |
15 14 13 12 11 |
10 9 8 7 6 |
5 4 3 2 1 0 |
|
6. Channel Alteration |
Channelization or dredging absent or minimal; stream with normal pattern. |
Some channelization present, usually in areas of bridge abutments; evidence of past channelization, i.e., dredging, (greater than past 20 yrs.) may be present, but recent channelization is not present. |
Channelization may be extensive; embankments or shoring structures present on both banks; and 40 to 80% of stream reach channelized and disrupted. |
Banks shored with gabion or cement; over 80% of the stream reach channelized and disrupted. In stream habitat greatly altered or removed entirely. |
|
SCORE |
20 19 18 17 16 |
15 14 13 12 11 |
10 9 8 7 6 |
5 4 3 2 1 0 |
|
7. Frequency of Riffles (or bends) |
Occurrence of riffles relatively frequent; ratio of distance between riffles divided by width of the stream <7:1 (generally 5 to 7); variety of habitat is key. In streams where riffles are continuous, placement of boulders or other large, natural obstruction is important. |
Occurrence of riffles infrequent; distance between riffles divided by the width of the stream is between 7 to 15. |
Occasional riffle or bend; bottom contours provide some habitat; distance between riffles divided by the width of the stream is between 15 to 25. |
Generally all flat water or shallow riffles; poor habitat; distance between riffles divided by the width of the stream is a ratio of >25. |
|
SCORE |
20 19 18 17 16 |
15 14 13 12 11 |
10 9 8 7 6 |
5 4 3 2 1 0 |
|
8. Bank Stability (score each bank)
Note: determine left or right side by facing downstream.
|
Banks stable; evidence of erosion or bank failure absent or minimal; little potential for future problems. <5% of bank affected. |
Moderately stable; infrequent, small areas of erosion mostly healed over. 5-30% of bank in reach has areas of erosion. |
Moderately unstable; 30-60% of bank in reach has areas of erosion; high erosion potential during floods. |
Unstable; many eroded areas; "raw" areas frequent along straight sections and bends; obvious bank sloughing; 60-100% of bank has erosional scars. |
|
SCORE _____ (LB) |
Left Bank 10 9
|
8 7 6 |
5 4 3 |
2 1 0 |
|
SCORE _____ (RB) |
Right Bank 10 9
|
8 7 6 |
5 4 3 |
2 1 0 |
|
9. Bank Vegetative Protection (score each bank) |
More than 90% of the streambank surfaces and immediate riparian zone covered by native vegetation, including trees, under story shrubs, or nonwoody macrophytes; vegetative disruption through grazing or mowing minimal or not evident; almost all plants allowed to grow naturally. |
70-90% of the streambank surfaces covered by native vegetation, but one class of plants is not well-represented; disruption evident but not affecting full plant growth potential to any great extent; more than one-half of the potential plant stubble height remaining. |
50-70% of the streambank surfaces covered by vegetation; disruption obvious; patches of bare soil or closely cropped vegetation common; less than one-half of the potential plant stubble height remaining. |
Less than 50% of the streambank surfaces covered by vegetation; disruption of streambank vegetation is very high; vegetation has been removed to 5 centimeters or less in average stubble height. |
|
SCORE _____ (LB) |
Left Bank 10 9
|
8 7 6 |
5 4 3 |
2 1 0 |
|
SCORE _____ (RB) |
Right Bank 10 9
|
8 7 6 |
5 4 3 |
2 1 0 |
|
10. Riparian Vegetative Zone Width (score each bank riparian zone) |
Width of riparian zone >18 meters; human activities (i.e., parking lots, roadbeds, clear-cuts, lawns, or crops) have not impacted zone. |
Width of riparian zone 12-18 meters; human activities have impacted zone only minimally. |
Width of riparian zone 6-12 meters; human activities have impacted zone a great deal. |
Width of riparian zone <6 meters: little or no riparian vegetation due to human activities. |
|
SCORE _____ (LB) |
Left Bank 10 9
|
8 7 6 |
5 4 3 |
2 1 0 |
|
SCORE _____ (RB) |
Right Bank 10 9
|
8 7 6 |
5 4 3 |
2 1 0 |