Black Branch 2

Small headwater stream in rural/agricultural setting east of Nashville. Low flow with sediment deposition over limestone bedrock suggests sedimentation stress. Riparian buffer compromised on right bank (downstream) by mowed grass extending to bank edge.

Channel appears relatively natural with no direct engineering modifications visible. However, the channel shows signs of mild incision with moderate bank heights relative to channel width. The exposed bedrock substrate and moderate bank angles suggest some downcutting has occurred, likely exacerbated by land use changes in the watershed. The channel maintains connection to its floodplain but is showing early signs of entrenchment.

Stream shows moderate incision with banks approximately 3-6 feet high for a channel that is only about 3-6 feet wide. The adjacent mowed areas suggest some hydrologic alteration from land use change. Floodplain access appears partially maintained but the incision ratio indicates reduced flood frequency. Agricultural/residential land use in the watershed likely contributes to altered hydrology.

Fine sediment (silt and mud) visible overlying bedrock substrate, particularly in the down view where turbid muddy water covers portions of the bed. Approximately 20-40% of the visible bed appears affected by fine sediment deposition. The bedrock substrate is partially obscured. Not severe enough to cause braiding but pool habitat is likely compromised by sedimentation.

At current low flow, the channel is dominated by shallow flow conditions. Visible flow is primarily slow-shallow in pools and fast-shallow over exposed bedrock. No deep pools or fast-deep areas are evident. The very low water level limits habitat diversity significantly.

Water fills approximately 50-75% of the active channel width. Exposed bedrock substrate visible in multiple areas as seen in the front view. Water is very shallow but continuous. Some areas show water touching bank bases while other sections have exposed substrate along the margins.

This appears to be a low-gradient stream where riffle-pool sequences are naturally less frequent. The bedrock substrate creates some shallow riffle-like areas where water flows over exposed rock, but the dominant morphology is runs and shallow glides. True riffles are infrequent based on the visible reach.

Small headwater stream with limestone bedrock bed. The channel appears moderately entrenched in a rural setting typical of Middle Tennessee. The bedrock control limits downcutting but the banks show moderate height suggesting some historical incision. The sinuous planform with moderate bank heights and bedrock bed is most consistent with a Rosgen F-type channel that has some bedrock grade control. The low gradient and moderate sinuosity support this classification.

Left bank (right bank when facing downstream, seen in left face image) has dense shrubby vegetation providing root stabilization. Bank height is moderate (3-6 ft) with steep angle. Vegetation cover provides some protection but the species composition appears to be predominantly invasive shrubs which provide less deep root stabilization than native trees. Minor erosion visible at the bank toe. Overall moderately stable.

Dense vegetation covers approximately 70-80% of the left bank when accounting for dormant season visibility. However, much of this appears to be invasive shrub species rather than native vegetation. The dense tangled growth provides surface protection but the invasive composition reduces the score. Some bare soil and litter visible at the bank face.

Left bank has dense invasive shrub coverage that provides some bank protection. Structures and possible fencing visible behind the riparian zone. Some litter present. Bank is steep with moderate height.

Right bank (left bank when facing downstream, seen in right face and front images) has mowed grass extending nearly to the bank edge with scattered trees. The grass provides minimal deep root protection at bank toe. Bank is moderate height (3-6 ft) with a moderate angle. Less stable than the left bank due to the absence of woody root systems at the bank face. Some scour evident at the bank toe.

Right bank has grass coverage over the bank top but the bank face shows bare soil and exposed bank material. Only scattered trees provide woody root protection. The mowing regime extends close to the bank edge, removing natural shrubby buffer vegetation. Approximately 50-60% of the bank face has adequate vegetative protection when considering both grass at top and exposed face.

Right bank is significantly compromised by mowing/grass management extending to the channel edge. Very minimal woody riparian buffer. Scattered mature trees provide limited bank protection but most of the bank face lacks deep root systems.

Left bank riparian zone has a relatively narrow strip of dense shrubby vegetation before transitioning to what appears to be developed/residential areas behind. The buffer width appears to be approximately 10-25 feet, which is roughly 0.5x the channel width. While the vegetation is dense, it is narrow and appears dominated by invasive species.

Right bank riparian buffer is essentially nonexistent. Mowed grass extends nearly to the bank edge with only scattered individual trees providing any woody cover. The functional buffer width is less than 10 feet and is dominated by mowed turf grass rather than natural vegetation. This severely compromises filtering and bank stabilization functions.

The floodplain vegetation is significantly altered. The right bank floodplain is mowed grass with scattered trees — a highly altered condition. The left bank has dense vegetation but is likely dominated by invasive species. Overall, the floodplain vegetation is not in a natural state and filtering/habitat functions are compromised.

Currently in winter with bare deciduous trees, canopy shade is under 25%. Even in full leaf, the right bank's scattered trees and the left bank's short shrubby vegetation would provide perhaps 25-40% shade. The open mowed area on the right bank ensures significant solar exposure. For a warmwater stream, this level of shade is below optimal.

The right bank represents the most critical buffer deficiency. The mowed grass field provides essentially zero riparian buffering function. Establishing a native riparian buffer of at least 30 feet on the right bank should be a high priority. The left bank would benefit from invasive species management and replanting with native trees and shrubs to improve buffer quality even if width is constrained.

Limited favorable substrate for colonization. The bedrock substrate provides stable surface but offers limited interstitial habitat. Some undercut bank areas and root masses from the left bank shrubs provide habitat, but woody debris is sparse and cobble/boulder habitat is limited. Approximately 20-30% of available substrate is favorable for epifaunal colonization.

The substrate is primarily bedrock with fine sediment (silt/mud) filling depressions and covering portions of the bed. The down face shows muddy/silty substrate with poor visibility. Fine sediment embeds what little gravel or cobble may be present. Root mats are limited to the left bank where shrub roots reach the water. Overall, the substrate condition is marginal for invertebrate habitat.

Pools are very shallow and infrequent. The bedrock-dominated channel does not create deep scour pools under current conditions. Most of the channel appears to be shallow runs and glides. Water depth is mostly under 6 inches. Pool bottom is largely discernible through the shallow water, though turbidity partially obscures the bed in some areas.

Fish cover is limited. Some overhanging vegetation from the left bank provides limited cover. Minor undercut bank areas and root masses offer shelter. However, deep pools, logs/woody debris, cobble/boulder habitat, macrophyte beds, and backwater pools are absent or very limited. Only 2-3 cover types are readily available.

No barriers to fish movement are visible within this reach. However, the very low water depth during low flow conditions may seasonally inhibit fish passage over exposed bedrock areas. No culverts, dams, or drop structures are visible in either the upstream or downstream views.

Very little large woody debris is present in the channel. Only small branches and twigs are visible. No debris jams or pool-forming LWD observed. The sparse mature tree population along the right bank and the invasive shrub dominance on the left bank contribute to the lack of LWD recruitment. The small channel size means even modest LWD would be beneficial but it is essentially absent.

Very limited invertebrate habitat diversity. The bedrock substrate provides stable surface but limited interstitial spaces. Some minor undercut bank areas on the left bank and scattered coarse material provide limited habitat. Fine sediment covers much of the bed. Leaf packs, submerged logs, cobble, and boulder habitat are essentially absent. Only 1-2 habitat types available for colonization.

Score assigned based on habitat quality suggesting Group II community potential. No direct observation possible from panoramic imagery. The moderate water quality and limited but present habitat features suggest a facultative community could persist.

No macroinvertebrates directly observed in imagery. Score based on habitat assessment suggesting the available habitat could support Group II (facultative) taxa. Winter conditions and low flow may suppress visible activity. The bedrock substrate with some silt would likely support moderate diversity of tolerant to facultative organisms.

Suitable Habitat: No

This small headwater stream in a modified landscape is unlikely to support rare or threatened species. Habitat quality is marginal. However, limestone bedrock streams in Tennessee can support unique invertebrate assemblages. Winter conditions limit direct wildlife observation.

No wildlife directly observed during survey. A broken snag/stump on the right bank could provide habitat for cavity-nesting birds in warmer months. The dense shrub thicket on the left bank likely provides cover for small mammals and songbirds. What appears to be a bird nest (ball-shaped) is visible in one of the bare trees in the right face image.

Water appears slightly turbid to turbid with a brownish color. In the front view, the substrate is partially visible through shallow water suggesting moderate clarity. In the down view, the water is more turbid with reduced visibility. No oil sheen, foam, or unusual odor indicators visible. The brown color may be partly from tannins and partly from suspended sediment. Visibility estimated at 0.5-1 foot.

No significant algal blooms or dense macrophyte growth observed. Water is not green-colored. The winter season may suppress visible algal/macrophyte growth. Minor algal growth may be present on substrate surfaces but is not conspicuous. No excessive nutrient enrichment indicators present during this observation.

No evidence of manure, livestock access, or waste discharge visible. The mowed grass area on the right bank could be pasture but no livestock, fencing (except possibly on the left), or manure deposits are visible. No waste discharge pipes detected. Score slightly reduced from maximum due to the agricultural land use context.

This small stream receives minimal shade, especially on the right bank side where mowed grass provides no canopy cover. In summer with full leaf-out, the left bank trees would provide some shade but the right bank would remain exposed. Establishing a woody riparian buffer on the right bank would significantly improve thermal conditions. Currently winter so thermal stress is not a factor, but summer conditions should be assessed.

The ongoing mowing of the right bank riparian zone to the channel edge represents a chronic disturbance to the riparian buffer. While this may not constitute a specific permit violation, it significantly degrades riparian buffer function and should be addressed through landowner outreach.

Terrestrial Invasives Assessment

Aquatic Invasives Assessment

The dense shrubby vegetation on the left bank has a growth pattern highly consistent with bush honeysuckle (Amur or Morrow's honeysuckle), which is extremely common in Middle Tennessee riparian areas. The tangled vine growth visible in the left face is consistent with Japanese honeysuckle. Some multiflora rose may also be present. These identifications are based on growth habit and morphology during dormancy — confidence is medium. Spring/summer assessment would confirm. The invasive shrub layer dominates approximately 26-50% of the visible riparian zone, primarily on the left bank.