Black Branch 2

Small headwater stream in agricultural/rural setting near Wilson County, TN. Very low flow at time of assessment. Bedrock-controlled channel suggests intermittent to perennial flow regime. The narrow channel and low flow make classification difficult. Adjacent agricultural land use and nearby residential structure (red-roofed building) suggest potential for non-point source influences.

Channel appears natural with no visible alterations, dikes, or engineered structures. Bedrock-controlled channel with natural sinuosity. No evidence of straightening or channelization. Minor natural erosion at banks but no excessive downcutting. Score of 8 reflects natural condition with very minor lateral erosion.

Channel shows slight incision into bedrock with banks 3-6 feet high on the right side. Floodplain appears connected on the left with lower banks. Agricultural land use in the watershed may have altered runoff patterns. The bedrock control limits downcutting. Score of 6 reflects minor hydrologic alteration likely from land use changes in the watershed.

Very little sediment deposition visible. Bedrock substrate is predominantly exposed with only minor fine sediment in crevices. No point bars or mid-channel bars observed. The bedrock-controlled channel naturally limits sediment storage. Score of 8 reflects minimal deposition, though this may partly be due to the bedrock control rather than low sediment supply.

At current low flow conditions, only shallow regimes are present. Water is uniformly shallow (under a few inches) flowing over bedrock as thin sheet flow. No deep pools visible at this location. Limited to slow-shallow in pooled areas and fast-shallow over bedrock runs. Score of 3 reflects only 2 regimes present, though this is partly a function of the very low flow conditions.

Water is present but at very low levels. Approximately 25-50% of the channel width contains flowing water, with exposed bedrock and dry channel margins visible on both sides. The thin sheet of water barely covers the bedrock substrate in the thalweg. Score of 3 reflects the limited channel coverage.

The bedrock-controlled channel creates some natural variation in flow, with minor riffles where bedrock ledges create steps. However, at this very low flow, distinct riffle-pool sequences are not well developed. The generally flat bedrock surface creates primarily uniform shallow runs. Score of 5 reflects moderate riffle occurrence controlled by bedrock geology.

This is a bedrock-controlled headwater stream in the Nashville Basin limestone region. The flat-lying limestone bedrock creates a channel with limited depth variability and high width-to-depth ratio. The moderate gradient and bedrock control suggest a B-type stream, though the high W/D ratio is somewhat atypical. The channel appears stable due to bedrock resistance to erosion. Bank erosion is limited. The asymmetric cross-section with a lower left bank and higher right bank is consistent with a slightly sinuous channel with preferential floodplain development on one side.

Left bank is moderately low with some areas of exposed soil and rock. Bank appears relatively stable with vegetation providing some root protection, though the dormant season reduces visible vegetation density. Some bare soil visible (26-50%) but much of this is natural rock exposure. Agricultural field is visible beyond a narrow riparian strip, suggesting the buffer is thin. Score of 6 reflects moderately stable conditions with minor concerns about the narrow buffer width.

Vegetation coverage is approximately 50-70% when accounting for dormant season conditions. Dense shrubs and small trees are present but the narrow riparian strip transitions quickly to open agricultural land. Early spring herbaceous growth is just beginning. Some bare soil and rock exposed along the bank face. Score of 5 reflects marginal vegetative protection, partly due to the narrow buffer and seasonal dormancy.

Left bank transitions from the channel edge through a narrow riparian strip of dormant shrubs and small trees to open agricultural fields. The narrow buffer width is a concern for filtering and bank protection. Bedrock at the channel bed provides natural grade control.

Right bank is moderate height (3-6 ft) with steep angle. Dense dormant shrub cover and some tree root systems provide stabilization. A large fallen tree on the bank could indicate past bank instability or wind damage. Some exposed rock and soil at the bank toe. Overall moderately stable with natural vegetation holding the bank. Score of 6 reflects moderate stability with the higher bank height being a concern.

Dense dormant shrubs and vines cover approximately 70-80% of the right bank face. Trees and woody vegetation provide root stabilization. The fallen tree reduces canopy cover at one point. Some bare soil and rock exposure at the bank toe. Score of 6 reflects generally adequate but not optimal vegetative protection, accounting for seasonal dormancy.

Right bank is taller and steeper than the left, with dense shrub coverage. A large fallen tree may indicate past bank instability. The red-roofed structure visible downstream appears to be on or near the right bank floodplain, suggesting some residential development in the corridor.

The left riparian buffer appears quite narrow, approximately 10-25 feet, before transitioning to open agricultural/pastoral land. For a channel approximately 5-8 feet wide, this represents roughly 2-3x channel width, but the absolute width is narrow. Open fields are clearly visible through the bare trees suggesting the buffer provides limited filtering capacity. Score of 4 reflects a buffer that is minimally adequate in width relative to channel width but may not meet absolute minimum standards.

The right riparian buffer appears somewhat wider than the left, approximately 25-50 feet, with denser woody vegetation. However, a structure (red roof building) is visible downstream suggesting development encroachment. The buffer provides moderate filtering and bank protection. Score of 6 reflects an adequate but not generous buffer width.

Some plants, bushes and trees are present along both banks and the narrow floodplain. The riparian zone includes a mix of shrubs, saplings, and some mature trees. However, the buffer is narrow on the left side and the vegetation is in winter dormancy. The transition to agricultural land limits floodplain vegetation extent. Score of 3 reflects fair conditions with adequate but not abundant riparian vegetation.

Currently in early spring with leafless canopy providing minimal shade (under 25%). However, the dense branch network visible in the UP face suggests that when fully leafed out, shade coverage would be approximately 50-75%. Scoring based on the expected growing season condition rather than current dormant state. When trees are in full leaf, moderate shade would be provided. However, the narrow buffer on the left means some of the channel will receive direct sunlight. Score of 6 reflects expected moderate shade conditions during the growing season.

The left bank riparian buffer is likely below the TDEC MS4 permit minimum of 30 feet. Agricultural fields extend close to the channel. Buffer restoration through planting native trees and shrubs along the left bank and expanding the existing buffer would significantly improve filtering capacity and bank stability. The right bank is marginally compliant with a structure visible in the downstream direction.

Substrate is predominantly flat bedrock which provides limited surface area for colonization by epifaunal organisms. Some favorable habitat is present in the form of loose rock fragments creating interstitial spaces, minor undercut banks, and woody debris. However, the bedrock-dominated channel limits colonization potential. Approximately 20-40% of substrate is favorable. Score of 4 reflects limited but present epifaunal substrate.

The bedrock-controlled channel has limited loose substrate to evaluate for embeddedness in the traditional sense. Where loose rock fragments and gravel are present, fine sediment coverage appears to be approximately 25-50%. The bedrock itself is relatively clean with only thin fine sediment deposits in crevices. Score of 7 reflects moderate embeddedness of available loose substrate.

Pools are essentially absent at this location under current low flow conditions. The flat bedrock substrate creates a nearly uniform depth profile. One small pooled area is visible in the left bank view but it is very shallow. Entire bottom is discernible throughout. Score of 2 reflects near-absence of meaningful pool habitat.

Limited fish cover is available. Some woody debris and branches are in and over the channel, overhanging dormant vegetation provides marginal cover, and minor undercut banks exist. However, deep pools, boulders, macrophyte beds, and backwater areas are absent. The very shallow water depth further limits fish cover utility. Score of 3 reflects 3 cover types present.

No physical barriers to fish movement visible in this view. However, the very low water depth at this location would effectively limit fish movement during low flow periods. The bedrock ledges create very minor grade changes but nothing constituting a barrier. Score of 8 reflects no engineered barriers but potential seasonal flow limitations.

Sparse to moderate woody debris present. A large fallen tree is visible on the right bank that could contribute LWD to the channel. Some smaller branches and woody material are in and over the channel. One piece appears to span the channel. No debris jams formed. Mix of size classes present including the large fallen tree. Score of 5 reflects sparse but present LWD with some size diversity.

Three types of macroinvertebrate habitat identified: fine woody debris in and along the channel margins, leaf packs accumulating in crevices and along banks, and some coarse gravel/rock fragments in the bedrock crevices. The predominantly flat bedrock substrate limits habitat diversity. Undercut banks are minimal. No submerged logs colonized for extended periods are visible. Score of 4 reflects limited but present habitat diversity.

Habitat assessment only - no direct observations of macroinvertebrates possible from panoramic imagery. Bedrock substrate with some interstitial spaces and leaf packs suggests potential for facultative organisms. Clean water conditions support this assessment.

No macroinvertebrates directly observed in the imagery. Assessment based on habitat availability only. The clean bedrock substrate, clear water, and presence of some habitat features suggest potential for at least Group II organisms. The early spring timing and low flow may limit observable activity. Score of 6 assigned based on habitat potential for Group II organisms, though direct observation was not possible from imagery.

Suitable Habitat: No

Limited habitat for species of concern at this location. The small, low-flow headwater stream with bedrock substrate provides minimal fish habitat. No mussel beds visible. The narrow riparian buffer and adjacent agricultural land use limit terrestrial wildlife habitat value.

No wildlife directly observed during assessment. Fallen tree on right bank provides some structural habitat. Dense shrub thickets could serve as songbird nesting habitat during breeding season. The bedrock stream with very low flow has limited aquatic habitat value for fish and other aquatic organisms.

Water appears generally clear with slight turbidity. The very shallow depth makes clarity assessment difficult, but the bottom is entirely visible. No discoloration, oil sheen, or film observed. Some minor brown coloration visible in the left bank standing pool area. Score of 7 reflects generally good water clarity with minor turbidity.

No algal growth or excessive macrophytes observed. Water is clear without green coloration. No algal mats on rocks. The bedrock substrate appears clean. However, the early spring timing and low flow may mask nutrient enrichment that could manifest during warmer months. Adjacent agricultural fields could be a non-point nutrient source. Score of 8 reflects good conditions at time of assessment.

No direct evidence of manure, waste, or livestock access visible at this location. However, adjacent agricultural/pastoral fields suggest potential for livestock access elsewhere along the reach. No waste discharge pipes, manure deposits, or related odor indicators observed. Score of 8 reflects no visible evidence at this point but acknowledging agricultural land use proximity.

Currently in dormant season with minimal canopy shade. When fully leafed, the riparian trees on both banks would provide moderate shade coverage. The narrow buffer on the left bank reduces shade potential. The very shallow water depth makes this stream highly susceptible to temperature fluctuations. No springs or groundwater seeps observed that would provide thermal refugia. Agricultural land use nearby does not appear to include significant impervious surfaces that would contribute heated stormwater.

No permit compliance concerns observed. The narrow left bank buffer adjacent to agricultural fields is a management concern but not necessarily a compliance violation at this location.

Terrestrial Invasives Assessment

Aquatic Invasives Assessment

Confidence is low due to dormant season timing making positive identification very difficult. The dense shrub layer on both banks includes some stems that are consistent with bush honeysuckle (Lonicera maackii) and privet (Ligustrum sp.) based on stem architecture and branching pattern, but positive ID requires leaf and flower confirmation. Some vine material in the canopy may be Japanese honeysuckle. A growing season revisit would greatly improve invasive species assessment accuracy.