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7. To determine the morphological conditions applicable to a lake or any part thereof, the Department must assign the hydromorphological characteristics of the lake or part thereof as being of the type specified in column 1 of Table 9 below which corresponds to the applicable measurements specified in columns 3 and 4 of that Table.
Site Altitude | Alkalinity (as mg/l CaCO3) | ||||
---|---|---|---|---|---|
Less than 10 | 10 to 50 | 50 to 100 | 100 to 200 | Over 200 | |
Under 80 metres | Type 1 | Type 2 | Type 3 | Type 5 | Type 7 |
Over 80 metres | Type 4 | Type 6 |
Final typology for dissolved oxygen, ammonia and biochemical oxygen demand in rivers | |
---|---|
Column 1 | Column 2 |
Upland and low alkalinity | Types (1+2), 4 and 6 |
Lowland and high alkalinity | Types 3, 5 and 7 |
Type | Characteristics | |||
---|---|---|---|---|
Bedrock channel | Normally high altitude | Channel cuts down laterally | May have waterfalls and/or cascades | Bedrock substrate |
Cascade Step Pool | Normally high altitude | Channel cuts down | Both turbulent and tranquil flows | Cobble and boulder substrate |
Pool-riffle-glide | Normally medium altitude | Often not confined within a valley | Slightly meandering | Pebble and cobble substrate |
Meandering | Normally low altitude | Flow laminar and would naturally interact with floodplain | Meandering | More fines than other substrates |
Column 1 | Column 2 | Column 3 | Column 4 | |
---|---|---|---|---|
Type | Standard Average Annual Rainfall mm (period 1961-1990) | Base Flow Index (BFI) | Catchment area (km2) | |
A1 | < 810.5 | < 0.715 | Any | |
≥ 0.715 | ≥ 251.8 | |||
A2 | < 810.5 | ≥ 0.715 | < 251.8 | ≤ 100 (A2 headwaters) > 100 (A2 downstream) |
≥ 810.5 and < 1413 | ≥ 0.7495 | Any | ≤ 100 (A2 headwaters) > 100 (A2 downstream) | |
B1 | ≥ 810.5 and < 1155 | ≥ 0.3615 and < 0.7495 | < 267.4 | |
B2 | ≥ 810.5 and < 1413 | ≥ 0.3615 and < 0.7495 | < 267.4 | |
C2 | ≥ 1155 and < 1413 | ≥ 0.3615 and < 0.7495 | < 267.4 | |
≥ 1413 | ≥ 0.3615 | ≥ 32.33 | ||
D2 | ≥ 1413 | ≥ 0.3615 | < 32.33 | |
≥ 810.5 | < 0.3615 | Any |
Geological category | Annual mean alkalinity (micro-equivalents per litre) |
---|---|
Low alkalinity | < 200 |
Moderate alkalinity | 200 – 1000 |
High alkalinity | > 1000 |
Marl |
Depth category | Mean depth (metres) |
---|---|
Very shallow | < 3 |
Shallow | 3 – 15 |
Deep | > 15 |
Colour category | Platinum (mg/l) |
---|---|
Humic | > 30 |
Non humic | ≤ 30 |
Categories | |
---|---|
Column 1 | Column 2 |
Peat | Non-Peat |
mean water colour ≥90 hazen units; or | mean water colour <90 hazen units; or |
≥75% of solid catchment area comprised of peat | <75% of solid catchment area comprised of peat |
Column 1 | Column 2 | Column 3 | Column 4 |
---|---|---|---|
Type | Lake-MImAS(1) code | Mean Depth | Alkalinity |
(1) Morphological Impact Assessment System | |||
Low Alkalinity Very Shallow | P/L-vS | <4m | < 20 mgl-1 CaCO3 |
Low Alkalinity Shallow/Deep | P/L-ShD | >4m | < 20 mgl-1 CaCO3 |
Moderate Alkalinity Very Shallow | MA-vS | <4m | 20 – 100 mgl-1 CaCO3 |
Moderate Alkalinity Shallow/Deep | MA-ShD | >4m | 20 – 100 mgl-1 CaCO3 |
High Alkalinity Very Shallow | HA/M-vS | <4m | > 100 mgl-1 CaCO3 |
High Alkalinity Shallow/Deep | HA/M-ShD | >4m | > 100 mgl-1 CaCO3 |
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