resources in the Greater Heretaunga and Ahuriri catchment area - - PowerPoint PPT Presentation

Making decisions for freshwater resources in the Greater Heretaunga and Ahuriri catchment area

March 2017

Welcome and Introductions

Outline of Presentations

• Purpose for this meeting
• Update on the TANK project
• What the TANK Group is considering
• A few sediment facts and what they mean for

your freshwater values

• Breakout sessions for discussion and feedback
• Farmer involvement – what is happening

already

• What else needs to happen?
• Support and advice
• Timelines

What the TANK project is about;

• The TANK Group is a community based collaborative

approach to developing a regional plan for the Ngaruroro Tutaekuri, Ahuriri and Karamu Catchments

• The TANK project is a process to;
• develop a shared understanding about important

freshwater values and how to provide for them

• enable better understanding of the science and the

issues

• result in more enduring solutions
• allow collective responsibility for outcomes
• reduce areas of contest in the Plan Change process

Greater Heretaunga and Ahuriri Land and Water Plan Change (TANK)

Catchments defined from surface water boundaries

TANK Update

A values-based approach to management

• Key Values;
• Ecosystem health and mauri of water
• Social and recreational values like swimming
• Other important values include;
• Irrigation
• Mahinga kai
• Domestic and urban supply
• Stock water
• Some of the ecosystem and social values are not

being met.

• A strong desire by the TANK Group to improve

the way we manage water resources

Increasing sediment deposited on stream bed

Clarity 2 m 10 20% cover Clarity 6 m 3% cover Clarity <1.5 m 17% cover

Sediment - Tutaekuri

Clarity 1.5 m 14% cover Clarity 2 m 25% cover

Very high DRP Moderate to high DIN Very low DRP Very low DIN Very high DRP high DIN

Nutrients and algae: Tutaekuri

High DRP moderate DIN Very high DRP Low to moderate DIN

Very high

All samples above guidelines

High

Most samples above guidelines

Moderate

most samples below guidelines but many above

Low

Most samples below stringent guidelines

Very low

All samples below all guidelines

Summary for Tutaekuri catchment

No issues with

• E. coli
• Nitrate and ammonia toxicity

Keep an eye on

• Nutrients, particularly P

 Algae, - lower Tutaekuri

• Sediment

Why is Sediment Management and Erosion Control is Important

• On farm benefits
• Production
• Stock health
• Amenity
• Farm infrastructure (fences, farm dams,

tracks, buildings)

• Etc
• Off-site benefits
• Biodiversity
• Amenity
• Protection of infrastructure

(roads/services)

• Water quality and ecosystem health

Why is there a focus on sediment?

• It means we can take advantage of

contaminant pathways;

• Phosphorous often attached to sediment
• Measures to reduce stream bank erosion can

also be effective at reducing bacteria levels

• Better riparian management can also reduce

losses of nitrogen

• Sediment is one of the key stressors for

ecosystem health;

• freshwater as well as estuary and the coast

Reducing Sediment Loss in the TANK catchments

Where from, how and how much?

Models and maps help predict and target the effect of different management approaches at a catchment scale

• Where most of the sediment is likely to

be coming from

• What type of erosion is resulting

in sediment loss

• Loss by location
• Worst water quality

Estimate of human influence on sediment loss

Current Hillslope erosion compared to forested catchment Catchment Pre-human Hillslope Sediment Load (t/yr) Current Hillslope Sediment Load (t/yr) Pre-human as %

• f current load

TANK (Tutaekuri) 90,394 333,651 27 TANK (Ahuriri) 8,009 54,723 15 TANK (Ngaruroro) 197,780 554,382 36 TANK (Karamu) 7,340 46,538 16 TANK hill country total 303,522 989,294 31

15

Landslide 50% Earthflow 1% Gully 6% Surficial 22% Bank erosion 21%

Breakdown of erosion types in TANK

Landslide Earthflow Gully Surficial Bank erosion

< 0 0 - 250 250 - 500 500 - 750 750 - 1000 1000 - 1250 > 1250

Sediment yield map of TANK area

High concentration of erodible land (Tutaekuri and eastern Ahuriri) t/km2/yr

Top 100 farms where if sediment plans were applied a 23% reduction in sediment would be expected.

Soil conservation and erosion control measures include;

• Retirement of steep erodible land
• Planting trees – forestry or space planting
• Debris dams
• Sediment ponds/wetland construction
• Stock exclusion
• Riparian planting
• Good pasture management
• Etc etc
• The effectiveness of each of these methods will vary

according to site specific characteristics +

• pportunities

From Catchment to Property Scale

• Modelling done at a catchment scale – but decision making

is done at a property scale

• Farm Plans can be a useful, practical tool to help;
• identify and address environmental risks and
• programme solutions
• monitor progress

so that you can farm in a way that is;

• environmentally sustainable,
• socially acceptable, and
• economically viable.

Assessing the costs…

Some things to consider.….

• Management options have been suggested –

1. a farmer led commitment plus

• bottom lines (rules) for some activities
• rules for some activities like cultivation,

winter grazing and protecting water from stock??

3. regulatory approach to farming imposed through plan rules and resource consents

• Rules about farm plans/farming
• National regulations for stock exclusion*
• Biodiversity strategy
• Govt Emissions Trading Scheme (forestry) and Afforestation

grants

• The TANK Group want to work with

farmers to;

• Agree on water quality and ecosystem

values and objectives

• Investigate the impact of a sediment

reduction target of up to 30% (of the total) and

• Show how this target might be met

• BREAKOUT DISCUSSION –
• Record and Report Back;
• What are the steps we can take to meet the

sediment management target?

• What else is needed for success?
• Help and resources you need to achieve

reduced sediment loss from your farm

• Timeframes
• Monitoring implementation

Some ideas……

Peter Kay - TANK Group pastoral farmer representative Mark Harris - Beef and Lamb NZ

Being involved – Being informed

• Next Steps;
• Farmer reference group
• Meeting 9th May
• Develop and discuss options
• Feedback to farming community
• Refine options
• Provide suggestions to TANK Group by

August 2017

• TANK group to prepare recommended draft

plan change by end of November 2017