HYDROLOGY
It would appear that the water replenishment in both Whistling Kite and Turtle Swamp are from a combination of precipitation and ground water, flowing in from the sparsely populated urban areas surrounding the wetlands. There is little drainage infrastructure resulting in most of the surface water flow following land slope, street formations and tracks, with erosion being the outcome in some situations.
The wet areas of Turtle Swamp and the large water body in Whistling Kite are both permanent with the water overflow from both wetlands flowing directly into Browns Bay.
GEOLOGY
The rocks underlying open forest areas and catchment areas in and surrounding both Turtle Swamp and Whistling Kite consist predominantly of sandstone, comglomerate, sedimentary, breccia, siltstone and shale.The soils within the central more wet areas of both Turtle Swamp and Whistling Kite are, as would be expected, comprised predominately of back swamp and coastal freshwater swamp sediments (sand, peat, mud).
In the areas adjacent to Browns Bay and Canaipa Passage are intertidal and supratidal deposits (silt, sand, mud), with some storm beach deposits between Browns Bay’s intertidal deposits and Turtle Swamp.
WATER QUALITY
Surface water in low lying areas is generally fresh and acidic. The acidity can mostly be attributed to the presence of organic acids that also impart a "tannin" colour to the water.
Below is the first group of tests taken on August 3, 2009. Our aim is to broaden the field of testing and increase the area of testing to include Moreton Bay adjacent to outflow points of the wetlands.
|
Parameter --> |
Temp |
Conductivity (µs/cm) |
Depth (m) |
pH |
Turbidity (NTU) |
D.O. (Mg/l) |
B.O.D (mg/L) |
Total Nitrogen |
Total Phosphorous |
Total Suspended Solids |
Algal Count |
|
Site 1 High Street (concrete plant) |
15.3 |
157 |
0.16 |
7.02 |
1.2 |
5.4 (54%) |
<5 |
0.19 |
0.01 |
ND |
|
|
Site 2 Minjerriba Road (culvert north) |
18.3 |
105 |
0.17 |
5.59 |
2 |
3.8 (40%) |
ND |
||||
|
Site 3 Minjerriba Road (culvert south) |
15.3 |
92 |
0.18 |
4.95 |
- |
2 (20%) |
<5 |
0.88 |
0.02 |
ND |
|
|
Site 4 Centre Road (culvert east) |
14.4 |
281 |
0.16 |
5.3 |
20.4 |
1.2 (10%) |
13 |
1.84 |
0.13 |
47,000 |
|
|
Site 5 Centre Road (culvert west) |
18.4 |
264 |
0.16 |
5.34 |
50.4 |
2.4 (25%) |
ND |
||||
|
Site 6 (Turtle Swamp) |
ND |
||||||||||
|
Site 7Centre Road (Turtle Swamp inlet drain) |
12.1 |
141 |
0.31 |
4.83 |
44 |
0.8 (12%) |
<5 |
0.58 |
0.02 |
ND |
|
|
Queensland Water Quality Guideline (QWG) values |
NV |
NV |
6.5 - 8.0 |
<50 NTU |
85 -110% Saturation |
NV |
<500 |
<50 |
<6 |
NV |
|
|
NV=no value |
ND=none |
detected |
