Black Branch 2

Small headwater stream in rural agricultural area east of Nashville (Wilson County area). Silt-dominated substrate with limited habitat diversity suggests sediment impairment. Adjacent pasture/residential land use with minimal riparian buffer contributes to habitat degradation.

Channel appears natural without direct structural alteration. However, adjacent land use (pasture extending to bank edge, lack of riparian buffer) has likely altered hydrology and sediment delivery, resulting in a channel that is slightly incised and laterally eroding in places. No straightening or armoring observed. Score of 6 reflects natural form with some degradation from land use impacts.

The channel shows slight incision with banks approximately 1.5-2 feet above the water surface. Floodplain appears accessible during moderate events. No major impoundments or withdrawals visible. Adjacent pastoral land use has likely increased flashiness of runoff. Score of 6 reflects slight alteration from land use changes.

The bed substrate is dominated by fine silt/mud, indicating significant fine sediment loading from adjacent pasture and agricultural land. While no large point bars are forming (channel is too small), the pervasive fine sediment coverage of the bed (~20-30% affected beyond natural conditions) suggests moderate sediment deposition issues. Score of 5 reflects noticeable sediment enrichment.

At this low-flow condition, the channel appears to be dominated by slow-shallow runs with occasional fast-shallow sections over rock. No deep pools or fast-deep habitat visible. The narrow, shallow channel provides limited velocity-depth diversity. Score of 3 for only 2 regimes apparent.

Water is present and flowing but does not fill the entire channel width. Approximately 50-75% of the channel bottom is wetted, with some exposed substrate along the margins. Score of 5 reflects moderate flow status.

The channel appears to be dominated by low-gradient runs with infrequent riffle features. Some rocky substrate creates shallow riffle-like conditions but true pool-riffle sequences appear rare. The flat gradient limits riffle development. Score of 4 reflects poor riffle habitat.

This appears to be a small headwater stream (1st or 2nd order) in a broad, flat valley in Middle Tennessee. The stream has a low gradient, moderate sinuosity, and fine-grained bed material. Channel is very narrow (2-3 feet) and shallow. The broad unconfined valley, low gradient, and sinuous planform suggest a Rosgen E-type channel, though confidence is low due to the very small channel size and silt/clay dominance (E-types more typically have sand/gravel beds). Could also be classified as a C-type given the low W/D and broad valley. The stream may be transitioning toward an F-type if incision continues.

Left bank shows moderate erosion with bare soil exposure at the bank edge. Bank height is low (1.5-2 feet) but the angle is moderate to steep in places. Limited root protection — mainly grass roots with scattered tree roots. Some active scour evident. Pasture extends close to bank limiting deep root protection. Score of 4 reflects moderately unstable conditions with limited root protection.

Left bank has approximately 50-65% vegetative coverage of the bank face, primarily dormant grass and scattered trees. In winter conditions, root mats from grass provide some protection but woody root mass is limited. Some bare soil patches visible. Buffer is very narrow. Score of 4 reflects compromised vegetative protection with significant gaps.

Left bank shows active erosion from pasture runoff and lack of woody riparian vegetation. Fencing partially visible suggesting livestock may be present or recently removed. Bank composed primarily of soil with some embedded limestone fragments.

Right bank appears somewhat more stable than left bank with a more gradual slope transitioning to the residential lawn area. Low bank height. Grass cover provides some protection but limited deep root mass. Less active erosion visible compared to left bank. Score of 5 reflects moderate stability with some concerns.

Right bank has grass extending to the stream edge, providing approximately 60-70% coverage. However, this is mowed turf grass with shallow root systems offering limited bank protection compared to native woody vegetation. No shrub or tree root reinforcement at the bank face. Score of 4 reflects reliance on grass-only protection with inadequate woody vegetation.

Right bank transitions to mowed residential lawn with gentle slope. Riparian buffer essentially absent — mowed grass extends to bank edge. Less erosion than left bank but vulnerable due to lack of woody root reinforcement.

Left bank riparian buffer is essentially absent to extremely narrow. A few scattered trees are present along the corridor but open pasture extends very close to the channel edge (within 5-10 feet). For a 3-foot wide channel, even 0.33x width would be only 1 foot. However, the functional riparian buffer (woody vegetation, native plantings) is virtually nonexistent. Score of 2 reflects severely compromised buffer width and function.

Right bank has no functional riparian buffer. Mowed residential lawn extends directly to the stream bank. No native woody vegetation or shrubs present in the buffer zone. Score of 1 reflects absent/completely compromised riparian function.

Floodplain vegetation is dominated by mowed grass and dormant pasture grass. Most trees and shrubs have been removed or never established. Some scattered trees remain along the corridor but overall the vegetation community is not in a natural state. Score of 2 reflects marginal floodplain vegetation.

Canopy cover is very low, estimated at less than 15-20%. The UP face confirms mostly open sky with only scattered bare tree branches. Even in full leaf season, the sparse trees would provide only partial shade. Score of 2 reflects inadequate canopy cover for a warmwater stream.

Both banks are severely deficient in riparian buffer relative to TDEC MS4 permit section 4.2.5.4 requirements. The 30-foot minimum buffer standard is not met on either side. High restoration potential exists if willing landowners can be engaged — the flat terrain and existing soil conditions would readily support tree/shrub plantings. This is a priority location for buffer restoration.

Very limited favorable epifaunal substrate. The channel bed is dominated by fine silt/mud with some embedded limestone fragments. No snags, logs, or significant woody debris in the channel. Very limited undercut banks. The few scattered tree roots near the bank offer minimal colonization potential. Score of 2 reflects severely lacking habitat substrate.

Bed substrate is predominantly mud and silt with some limestone fragments that are heavily embedded (>75% surrounded by fine sediment). Limited gravel or sand visible. Some root mats present along banks but sparse. Score of 3 reflects mud-dominated conditions in this low-gradient stream.

Pools are essentially absent in this reach. The entire channel bottom is discernible due to the shallow water depth (generally <6 inches). Occasional slightly deeper spots may exist at bends but no significant pool habitat is visible. Score of 2 reflects near-absence of pool habitat.

Very limited fish cover. The only cover types available are occasional overhanging grass/herbaceous vegetation and minor root mats at the bank edge. No logs, deep pools, boulders, undercut banks, macrophyte beds, or backwater pools observed. Score of 2 reflects severely deficient fish cover for this headwater stream.

No physical barriers to fish movement visible in this reach. However, the extremely shallow water depth during low flow may seasonally limit fish access to this headwater section. Score of 8 reflects no constructed barriers but potential seasonal flow limitations.

Large woody debris is essentially absent. Only minor small twigs and branch fragments observed. No debris jams, no pool-forming wood, no channel-spanning features. The lack of mature riparian trees means virtually no LWD recruitment source exists. Score of 1 reflects absent LWD.

Very limited invertebrate habitat. The channel bed is primarily fine silt/mud with a few embedded limestone fragments that could provide limited hard substrate for colonization. No leaf packs, submerged logs, fine woody debris, cobble riffles, or significant undercut banks observed. Score of 2 reflects severely deficient invertebrate habitat.

No organisms directly visible in imagery. Score based on habitat quality assessment — the silt-dominated, habitat-poor conditions would likely support only tolerant macroinvertebrate communities.

No macroinvertebrates directly observed from imagery. However, the limited habitat (fine sediment dominance, lack of cobble/gravel riffles, minimal woody debris) suggests that tolerant taxa (Group III) would likely dominate if sampled. Winter conditions may reduce visible surface activity. Score of 2 reflects expected community based on available habitat.

Suitable Habitat: No

This degraded headwater reach with limited habitat diversity, minimal riparian buffer, and fine sediment dominance is unlikely to support species of concern. The stream may provide seasonal habitat for common amphibians but overall wildlife habitat value is low.

No wildlife directly observed during survey. Winter conditions and human presence (surveyor wading) likely suppress visible activity. The limited instream habitat and narrow, buffer-less corridor reduce overall wildlife habitat value.

Water has a brown/tan coloration typical of streams with fine sediment substrates. Clarity appears moderate — objects on the bed are visible but water has noticeable turbidity. No oil sheen, foam, or algal growth observed. The brown color may be partly natural (dissolved organics from leaf litter) but likely also reflects fine sediment suspension. Score of 5 reflects fair water appearance with moderate turbidity.

No visible algal mats, excessive algal growth, or dense macrophyte stands. Water is not green. Some minor algal film may be present on rocks but not excessive. The winter season may limit visible nutrient enrichment signs. Adjacent pasture could contribute nutrients but current conditions don't show severe enrichment. Score of 7 for minimal visible nutrient enrichment indicators.

Fencing is partially visible on the left bank side suggesting potential livestock access or recent fencing for exclusion. Adjacent pasture land could support livestock. No manure is directly visible in or near the stream, and no waste pipes or discharge observed. However, the pastoral land use and fencing suggest potential livestock access. Score of 7 reflects possible but not confirmed livestock impact.

Stream has very limited shade cover due to absent/minimal riparian buffer. During summer months, this reach would be fully exposed to solar radiation for most of the day. While thermal stress indicators are not evident during winter survey conditions, the lack of canopy would likely result in elevated summer water temperatures. Riparian buffer restoration would significantly improve thermal conditions.

No active permit violations observed. However, the chronic lack of riparian buffer should be noted for future buffer restoration planning under MS4 programs.

Terrestrial Invasives Assessment

Aquatic Invasives Assessment

Confidence in invasive species assessment is low due to winter dormancy — most terrestrial invasives are difficult to identify without foliage. The eastern red cedar visible in the left bank view is native. Some of the scattered shrubby vegetation along the corridor could potentially be bush honeysuckle or multiflora rose but cannot be confirmed in winter dormant condition. A follow-up assessment during the growing season (May-August) is recommended for proper invasive species identification.