24 WKP- sites. Fish abundances were higher at both WKP- sites, than T-Stream sites, with 85 and 104 individuals recorded at WKP-3 and WKP-2, respectively. This increase in abundance and diversity is as expected with the waterfall restricting fish passage upstream. Fish QIBI scores were within the excellent category which is comparable to the best conditions without human disturbance, with all regionally expected fish species for the stream position represented (WRC 2007; Table 2). 7.3.6 Warm spring A warm spring (Ca. 19-20oC) emerges from the ground some 5 m from the true right bank of the main stem of the Wharekirauponga Stream between the Thompson and the Edmonds Stream tributaries (near the “R” tributary), 120 m upstream of the hydrological monitoring site named WKP 3. It has been measured with a flow of Ca. 2.5L/s. The emergence is a pool area heavy in orange algae (taxa unknown), following the spring pool the water passes as a shallow sheet flow (also heavy in bed orange algae) some 5 m to meet the main stem falling down a small bank (falls) into the Wharekirauponga Stream. There is minimal aquatic habitat present, and it is poor habitat for macroinvertebrates and fish as it is shallow and smothered in heavy algae (Figure 5). No fish were observed and are unlikely to be present in this shallow short reach, raised from the main stem “reach”. Two macroinvertebrate samples (samples a and b, Table 9) were taken to understand the value of the aquatic community in this feature, as we wanted to understand if the specific chemistry has produced an unusual aquatic macroinvertebrate community (Table 9). The common snail Potampoyrgus antipodarum was the dominant organism within the watercourse. No unique or unusual macroinvertebrates were encountered. GWS (2021) sampled the spring waters and show that it has moderately raised SO4, Sodium, moderate raised metals and is a calcium bicarbonate dominant water type. It is sufficiently unusual in the environs as to reduce the diversity and abundance of the typical macroinvertebrate and floral community, by excluding species intolerant of the specific water quality characteristics, but not so unusual as to produce a unique flora and fauna community. The ecological value is assessed as Low. The warm spring enters the Wharekirauponga Stream contributing warm fluids to the cool freshwater ecosystem. There may be some local influence of the discharge within the Wharekirauponga Stream, notably from sulphate, but we would expect that to dissipate rapidly within the receiving environment.
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