PAUP EXPERT CONFERENCING
Subject
Freshwater Ecology related to C.5.14: Lakes, rivers, streams and wetland
management
Scope
The scope of the conferencing was specified at IHP facilitated mediation held on the
12 and 25 May 2015 and included matters relating to the definition of stream types
and their associated values and management approaches as described in the PAUP
Chapter C.5.14, specifically;
1.
2.
3.
4.
The definition of permanent, intermittent and ephemeral streams
The values of the three types of stream
Potential RDA “matters of discretion” for works in intermittent streams.
Identify the considerations that should be taken into account if or when any
application is made for an activity on intermittent streams or any activity
affecting intermittent streams
Bullet points 1 to 3 arose from the first mediation session held on the 12 May.
Bullet point 4 was a modified request following a verbal report of the expert
conferencing to mediation on the 25 May and superseded the original bullet 3.
The experts met for two sessions on the 20th and 25th May 2015.
Attendees
Both sessions;
Brett Ogilvie (Tonkin & Taylor/NZTA)
Ian Boothroyd (Boffa Miskell/Southern Gateway)
Grant Dumbell (Aranovus/Gibbs Foundation)
Adam Daniel (Fish & Game)
Wolfgang Kanz (Auckland Council)
Martin Neale (Golder Associates/Auckland Council)
First session only;
Ben Woodward (Department of Conservation)
1. Definition
The group discussed three issues associated with the current set of definitions as
detailed in the PAUP;
1. Definition of intermittent is ‘negative’, in that it is encompasses streams that
do not meet the definition of ephemeral and permanent streams (i.e.
intermittent is defined by ‘exclusion’ from these other stream types. It was
agreed that because the PAUP is attempting to manage intermittent streams,
there needs to be a ‘positive’ definition for this category.
2. The criteria used to determine ephemeral stream type are framed in a
negative manner (i.e. the absence of a characteristic)
3. Intermittent category too broad, including streams that may contain water all
year round (i.e. stable pools) and those that may be dry for part of the year.
Agreement;
There was agreement by all on issues 1 and 2. Furthermore, it was agreed that the
proposed revisions to the definitions described below would address these issues.
Permanent – The continually flowing reaches of any river or stream
Intermittent – Stream reaches that cease to flow for some periods of the year
because the bed can be above the water table at some times.
This category is defined by those stream reaches that do not meet the definition of
permanent and meet at least three of the following criteria;
•
•
•
•
•
•
It has natural pools
It has a well-defined channel, such that the bed and banks can be
distinguished
It contains surface water more than 48 hours after a rain event which results
in stream flow
Rooted terrestrial vegetation is not established across the entire crosssectional width of the channel
Organic debris resulting from flood can be seen on the floodplain
There is evidence of substrate sorting process, including scour and deposition
Ephemeral – Stream reaches with a bed above the water table at all times, with
water only flowing during and shortly after rain events.
This category is defined as those stream reaches that do not meet the definition of
permanent or intermittent.
Outstanding issue;
There was a difference of opinion on issue 3. Grant was of the opinion that greater
differentiation of types of intermittent streams (i.e. with pools, without pools) is
merited, with a different management regime applied to those different types of
intermittent. This position was not supported by the other members of the group.
2. Values
There were differing views on the values (including ecological, hydraulic, biodiversity,
biogeochemical and functional) of intermittent streams.
It was agreed that the values of permanent, intermittent and ephemeral streams are
not identical.
There was no agreement on the existence of a hierarchy of values with regards to
intermittent and permanent streams. For some values it was considered that
intermittent streams may be of greater importance than permanent streams and vice
versa, but we were unable to reach a consensus on this issue.
3. Matters of discretion
This topic was superseded by the instructions from mediation on 25 May (reported in
bullet 4 below).
4. Considerations for activities in intermittent streams.
It was reported back to mediation on 25 May that the experts were unable to agree
on the relative values of the permanent and intermittent streams.
The mediation group subsequently requested the experts to report back on a further
request, that being ‘identify the considerations that should be taken into account if or
when any application is made for an activity on intermittent streams or any activity
affecting intermittent streams’
There was agreement that the considerations should be;
A. Whether suitable alternatives can be implemented
B. The existing and potential values of the stream and its catchment and the
effects of the activity on those values, including ecological, hydrological,
recreational, cultural and natural character values
C. The ability of aquatic fauna to utilise habitats (including refugia) and move
upstream and downstream, including the relevance and provision of fish
passage
D. Effects on downstream environments arising directly from the activity, and any
effects arising from any permanent modification in stream state or function
caused by the activity
E. The extent to which any effects that cannot be avoided, remedied or mitigated
are offset
F. The construction methodology, including the timing and duration of the activity
and erosion and sediment controls
G. Upstream or downstream flooding effects
H. Effects on any scheduled historic heritage place or scheduled sites and
places of significance to Mana Whenua
5. Additional matters
Activity table
Brett, Ian and Grant were supportive of an additional column in the activity table to
relate specifically to activities in intermittent streams, where the activity status of
these activities in intermittent streams could be different to their status in permanent
streams. Wolfgang, Martin, Adam and Ben did not support different status for
activities in intermittent streams. It is possible that the activity status for some
activities could differ between intermittent and permanent streams based on effects,
but the activities were not assessed in that context and the group was unable to
reach a consensus on this issue.
It was agreed that reclaiming (piping) intermittent streams was an undesirable
outcome and the activity status for such an activity should act as a deterrent to doing
so.
Artificial and modified streams
Grant raised concerns about artificial and modified watercourse and how they are
managed using the activity table. It was noted that the PAUP definition of a river or
stream includes ‘modified’ watercourses, but not ‘artificial’.
Brett raised a related concern about the activity status of partial removal of existing
structures from such modified streams.