Little Shoal Bay Stream Assessment
Summary of report findings
Development of the Little Shoal Bay Stream catchment began during the late 1800s and early 1900s, and in 1918 Edward Le Roy purchased much of the area, installing lily ponds, culverting the stream and introducing flora and fauna from other areas of New Zealand. The catchment is now fully developed and the remnants of Le Roy’s pipe network still remain within the upper main channel forming a restriction to flows. During the late 1950s and early 1960s the estuary in the lower catchment was reclaimed allowing a freshwater wetland to form. The stream otherwise still largely retains its natural morphology.
Documents
Little Shoal Bay Stream report PDF 
(929KB)
Little Shoal Bay Stream maps (PDFs)
Links
North Shore stream assessments overview page
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| Length | 3.8km | |
| Size Of Catchment | 97ha | |
| Vegetation Cover | 40% (39 ha), generally associated with the stream network. | |
| Imperviousness | 30% | |
| District Plan Land Use | Business | 7% |
| Recreation | 22% | |
| Residential | 59% | |
| Road | 12% | |
| Recreational Use | High, known high public use of the stream locality. | |
| Receiving Environment | Little Shoal Bay, Waitemata Harbour. | |
| Substrate | Silt/mud throughout the lower reaches, bedrock in the most of the upper tributaries. | |
| Natural Wetlands | Nil. | |
| Artificial Wetlands | 1 | |
| Periphyton | Below nuisance levels. | |
| Macrophytes | Possible management issues in Tributary 1. | |
| Macroinvertebrates | High species richness and MCI score. | |
| Fish | 4 species of native fish | |
| Potential Man-Made Barriers to Fish Passage to Upstream Habitat | 3 | |
| Channel Modification | Modified wetland in the lower main channel and old broken stormwater pipes in the upper main channel. | |
| Erosion around Structures | 4 structures with severe erosion, 3 with moderate erosion, and 1 with slight erosion. | |
| Bank Erosion | Slight throughout main channel, severe erosion in Tributary 2, and minor to moderate erosion in Tributaries 4, 5, 5A and 6. | |
| Temperature | One measurement indicating no adverse effect on ecology, however summer temperatures are likely to be higher. | |
| Suspended Solids, Turbidity And Visual Clarity | 3 clarity measurements, high in wetland + below average clarity for North Shore streams in Tributary 2 and the main channel. | |
| Oxygen and Oxygen Demand | Depressed oxygen concentrations in the upper and lower stream. | |
| Nutrients | No data. | |
| Contaminants | No data. | |
| Bacteria and Pathogens | No data. | |
| Sediment Quality | No data. | |
| Debris | Nil other than old channel pipes. | |
| Stream Grouping | Group 2, High value low disturbance | 52% |
| Group 3a, Urban semi-modified | 42% | |
| Group 3b, Urban modified | - | |
| Group 4, Concrete lined channel | 2% | |
| Group 5, Piped section | 2% | |