Drain maintenance rule Key issues & proposed amendments - - PowerPoint PPT Presentation

Drain maintenance rule –

Key issues & proposed amendments

Definitions

• artificial farm drainage canal
• drain
• highly modified river or stream

Concerns

• complex, lack clarity, please map
• water races, stormwater network, channels

that flow only during rainfall?

Proposed amendments

• New method: Map drains and highly

modified water courses

• Rationalise and reword definitions

Artificial farm drainage canal – delete Farm Drain

An open watercourse, designed and constructed for the purpose of land drainage of surface or subsurface water from farmland. (Note - Most watercourses considered to be farm drains are actually natural watercourses that have been highly modified, often over many decades, and include channels dug to drain natural wetlands.)

Highly modified river or stream:

For the purposes of Rule R121 only, means a river or stream that has been modified and channelled for the purpose of land drainage of surface or sub-surface water and has the following characteristics:

• it has been channelled into a single flow, and
• the channel is predominantly straight, with no

‘natural curves’, and

• the channel is mechanically formed with straight or

steeply angled banks, and

• it exhibits these characteristics for its entire length

through the property in which the activity is being carried out and downstream to the next confluence. Note: Water races, the stormwater network, and artificial channels that only convey water during rainfall events are not highly modified rivers or streams.

Do the amended definitions make it easier to interpret which watercourses are covered by Rule R121?

Methods

• Method M14 drain maintenance education

programme

Concerns

• highlight collaboration with industry and

landowners

Proposed amendments

• Highlight importance of working with landowners &

industry

• Information to increase understanding of ‘drains’ as

natural waterways and their ecological values

• Support land management practices to reduce

inputs of sediment and nutrients reducing need for ‘drain’ maintenance

R121(e) Sediment management

R121(e) excludes sediment condition

• impossible to meet
• step-wise improvement
• amend R121(k) to require sediment trapping

+ Method M14 to support practice change

Discuss under clause (k)

R121(f) Changes in grade or x-section

• Provide for fish refuge bays & livestock drinking

bays

Proposed amendments

• Add ‘for purpose of constructing a fish refuge bay’ (link to

clause (j))

R121(g) Weed bucket

Concerns

• Bucket specification too detailed

Proposed amendments

• Delete clause (g)

R121(h) Return of fish

Concerns

• clause is impractical - amend to take ‘all reasonable steps’ to

return fish

• require kakahi to be returned too

Proposed amendments

• maintain clause, minor rewording
• add kakahi

R121 (i) sediment spread

• Minor amendments for clarification

R121(j) Fish refuge

Concerns

• Clause is impracticable and inefficient

Proposed amendments

• Clarify intent to provide fish refuge
• Provide options:

(i) If waterway is wide enough, clear only one side or (ii) Leave vegetated refuge areas at intervals or (iii) Construct fish refuge bays at intervals

Are amendments to provide options supported? Are the following metrics about right:

• a fish refuge area every 200m length of

watercourse

• a 10m long vegetated buffer
• a 1m2 fish refuge bay

R121(k) Sediment trapping

Concerns

• Working downstream is impractical

Amendments

• Replace with requirement for a sediment

trap (a vegetation buffer or an installation) Are these amendments supported ?

Biosecurity (change to note)

• Add a note to highlight need to comply

with the Biosecurity Act

R121(new): Notification

• Request notification to understand

practice Is this addition supported ?

Drain Any artificial watercourse, open or piped watercourse, designed and constructed for the purpose of land drainage of surface or subsurface water and, for the purpose of Rule R121 only, excluding any ‘device’ included within the definition of stormwater

• network. Channels designed and constructed to convey water
• nly during rainfall events and which do not convey or retain water

at other times are excluded from this definition. Only for the purpose of Rule R121 (drain clearance) a drain also includes a highly modified watercourse or river and is channelled to such an extent that it has the characteristics of a farm drainage canal.

Note: For the avoidance of doubt, this definition does not include water races or artificial channels or swales that

• nly convey water during rainfall events.

Many watercourses that are considered to be drains are actually natural watercourses that have been highly modified, often over many decades, and include channels dug to drain natural wetlands.

For the purposes of Rule R121 only, means a river or stream that has been modified and channelled for the purpose of land drainage of surface or sub-surface water and has the following characteristics: to the extent that it has the characteristics of (in form or function) an artificial farm drainage canal. For the purposes of this definition, the characteristics of a farm drainage canal are considered to include that;

• it has been channelled into a single flow, and
• the channel has been straightened is straight, with no ‘natural

curves’, and

• the channel is mechanically formed with straight or steeply

angled banks, and

• it is maintained to keep the water table at least 0.3m below the

root zone of the surrounding pasture, and

• that it exhibits these characteristics for at least its entire length

through the property in which the activity is being carried out watercourse is being assessed.

Note: Artificial channels that only convey water during rainfall events, water races and the stormwater network are not Highly modified rivers or streams