Lecture 4, 5, 6, 7 - Guest Lectures

Question 1

Water Quality

Answer 1

• Our native freshwater species and ecosystems are under threat
• More information available in latest report - ‘Our fresh water 2020’
• EVIDENCE-BASED ASSESSMENTS (data is important)

Question 2

WRC’s river water quality monitoring network

Answer 2

Identify STATE and TRENDS

Question 3

New Developments

Answer 3

Need Baselines
Baselines
- Emerging contaminants:
o Glyphosate (herbicide)
o PFOS, PFOA Flame retardants
- New methods are evolving every year
- DNA, genetic monitoring - can tell sources of toxins

Question 4

Sources of sediments and contaminants

Answer 4

Dairy Farming - effluent, trampling

- Used to be small scale - now large-scale increased stresses

Question 5

Waikato River trends with examples

Answer 5

some improvement (ammonia, chlorophyll);
some deterioration (turbidity, nitrogen)

Question 6

Cause for an increase in nitrogen?

Answer 6

Pastoral agriculture

Question 7

Lake monitoring

Answer 7

Depths and stratifications important

Question 8

Important considerations for Water Monitoring

Answer 8

• Must consider effect of flow when interpreting water quality data
• Long term data-sets are important
• Timing of sampling is important - diurnal and seasonal changes.
• What to measure depends on what you want to achieve.

Question 9

Water quantity

Answer 9

Defining allocation limits

level and flow monitors

Question 10

How to Measure flow

Answer 10

weight off bridge with rotating device more rotations = increased flow (Large River)
Small river = flow meter + person
ADCP- automatic device tells you speed (radar)

If you change how, you measure - compare data and show relationship between methods (long term data sets)

Stage better than flow

Question 11

Ratings Curve

Answer 11

• Can change due to effects such as weed growth (i.e. seasonal effect) or channel morphology changing
  Water level is monitored continuously and converted to flow time series with a rating equation

Question 12

Monitoring river flow helps to determine

Answer 12

• Minimum flows for allocation
• Peak flows for flood protection
• Flow variability
• Temporal and spatial variations
  o Seasonal variability
  o Climate influences
  o Land use change

Question 13

Q5

Answer 13

1 in 5 year, 7-day low flow statistic

Question 14

Worrying trends

Answer 14

= 6 of the 7 driest summers on record have occurred since 2008

Question 15

Coastal monitoring

Answer 15

• Waikato coastal marine area
  o over 10,000 km2
• Monitoring includes:
  o the health of estuaries (benthic ecology, sedimentation and sediment quality, vegetation and water quality)
• Shoreline change monitoring
• Sea level monitoring
• Coastal water quality for contact recreation

Question 16

SOE monitoring

Answer 16

= To be able to assess the state of, and broad-scale changes in, the coastal marine area of the Waikato region, and to be able to assess the effect of activities on the coastal marine area.

Key Points

• Water quality
• Biodiversity - indigenous habitats and species
• Sediment quantity and quality

Question 17

Site selection

Answer 17

Many pressures clustered around estuaries especially:

• Coromandel Harbour,
• Whitianga Harbour,
• Tairua Harbour,
• the Firth of Thames,
• Whaingaroa (Raglan) Harbour

Question 18

Monitor for estuarine health

Answer 18

• Measured intertidal macroinvertebrates, sediment quality and sediment deposition rates at five sites in each estuary
• Use data to assess state and trends in estuarine health

Question 19

DPSIR

Answer 19

Drivers, pressures, state, impact, response

Question 20

Future Directions

Answer 20

• Align health monitoring across various ecosystems
• Fit within the DPSIR framework
• Use environmental indicators in our reporting