nick paling lecture on river catchment water quality assessment

Upstream Thinking Spatial data and analysis in the improvement of aquatic ecosystem health and downstream water quality

The Tamar Catchment

1,800km2 and 300,000+ people

It provide us with.

food and materials

energy / fuel

drinking water

It regulates.

climate gases

flooding & drought

It also gives us areas for.

culture

recreation

habitat for wildlife

A catchment provides many

Ecosystem Services

Many pressures act to reduce ecosystem health

Contribution of pollution from diffuse sources in the catchment

Nutrients

Phosphorus compounds Nitrates/Nitrites Ammonia compounds Physico-chemistry

Dissolved oxygen Colour Turbidity / suspended solids Smell & taste

Microbiology

Faecal indicator organisms (FIO) Other bacteria Cryptosporidium spp. Algae Pesticides

Acid herbicides Neutral herbicides Insecticides

Many pressures act to reduce ecosystem health

Reduced ecosystem health impairs service provision

Heavily exploited ecosystem Natural ecosystem

Provisioning services Regulating services

Cultural services

Crops

Meat

Timber

Spaces for Wildlife

Recreation

Pest control

Water regulation Water purification

What services are we currently getting?

A participatory stakeholder-led approach

What services do we get?

Are we getting enough?

What areas effect provision?

What can we do to provision?

Where should they be targeted?

How is it funded?

What are the outcomes?

Are the new sources of funding?

Developing a shared vision & a shared language

- Habitat creation

- Landuse change

- Farm infrastructure

- Best practice advice

- Stewardship

- Water Company

- Biodiversity offsetting

- Flood Risk

- Research findings

- Spatial data

- Monitoring

- Reports & plans

Ecosystem services: Water regulation & quality

The water cycle is one of the fundamental processes we all depend on

Water regulation is dependent on -

Direction of water movement: laterally or vertically

Rate of water movement / timing of release

Interactions with contaminants

Some land areas play a role in water regulation and water quality

- Innate characteristics

- Condition/health

Ecosystem services: Water regulation & purification

3

4

3

6 9

6 2

2 1

INHERENT RISK

PR

AC

TIC

E

Source

Receptor

We want to understand why water quality is (or is not) degraded in certain locations

+++ Importance/opportunity


Seasonally wet gley

3

4

3

6 9

6 2

2 1

INHERENT RISK

PR

AC

TIC

E

Identifying areas of high importance/risk to water regulation

- Soil type & condition/practices

Free-draining brown earth

Gley with impeded drainage

Natural habitat

Cultivated land

3

4

3

6 9

6 2

2 1

INHERENT RISK

PR

AC

TIC

E

Permanent pasture



- Landuse & practice (intensity of use)

Direct connection to watercourse

Steeply sloping

3

4

3

6 9

6 2

2 1

INHERENT RISK

PR

AC

TIC

E

Hydrologically connected



- Location, topography & hydrological connectivity

Water Quality

Soil hydrology & condition

Run-off risk

Leaching risk

Topography (i.e. slope)

Hydrological connectivity

Proximity to watercourse

Flood plain

Surface & sub-surface flow accumulation

Land cover

Natural habitats (wetland, woodland or peatland)

Farmed land (tillage or permanent grass)

The group identified land most likely to have an impact on water quality:

Case study: South West Waters Crownhill WTWs

For SWW: Water Supply + Pollution = Risk + Cost

Crownhill WTWs

60 Ml/day

80,000 households in Plymouth & South Hams

3 raw water sources

- Burrator Reservoir

- Tamar at Gunnislake

- Tavy at Lopwell Dam

SWW change the raw water sources for Crownhill WTWs according to various pressures

Where is the ecosystem service derived?

BUT

changing the source can have a significant impact on the treatment process

RISK

COSTS

Challenges at the water treatment works


Increased treatment cost = Pumping + Purification

Using river sources increases the cost of treatment


Suspended sediment & turbidity

We need determine the scale of the problems and where they are derived from in the catchment

if we dont know this, how can we possibly estimate the potential for enhanced ecosystem service (clean raw water) delivery?

Sources of pollution in the catchment


River walkover surveys (APEM 2010)


653 pollutions found.


The sediment run-off risk model helps us to quantify the scale of the

problem & target high risk areas

Challenges at the water treatment works (WTWs)

Nutrients: Phosphorus



Morse et al., (1993)



P point

sources

PSYCHIC (ADAS, 2004)



P livestock sources

P Total

PSYCHIC (ADAS, 2004)



Total P

A well established toolbox of measures to reduce rural diffuse pollution

Improving water quality toolbox of measures

Improving water quality toolbox of measures

A well established toolbox of measures to reduce rural diffuse pollution

*

Assessing the prospects for improvement

ECM+ for predicting phosphorus export

Scenario 2: 100% uptake of BFPs on Caudworthy

Scenario 1: Current situation

*

Scenario 2: 100% uptake of BFPs on Caudworthy

Scenario 1: Current situation

Scenario 3: 100% uptake of BFPs on entire Tamar

Assessing the prospects for improvement

ECM+ for predicting phosphorus export

It provide us with.

food and materials

energy / fuel

drinking water

It regulates.

climate gases

flooding & drought

It also gives us areas for.

culture

recreation

habitat for wildlife

A catchment provides many

Ecosystem Services

Flooding Drought

Spaces for wildlife Carbon sequestration

Land value Recreational resources

Bringing it all together

We now have a shared understanding of what outcomes will come from a better catchment, who will benefit and importantly who might pay

Ecosystem Sustainability Meter

nick paling lecture on river catchment water quality assessment

Environment

water regulation quality

water regulation purification

water regulation location

water cycle

downstream water quality

connected ecosystem

direction of water movement

areas of high importancerisk