IN THE MATTER of the Resource Management Act 1991

Transcription

1 IN THE MATTER of the Resource Management Act 1991 AND IN THE MATTER of an application pursuant to Section 201 for a Water Conservation Order on the Hurunui River. STATEMENT OF REBUTTAL EVIDENCE OF DAVOR BEJAKOVICH ON BEHALF OF NORTH CANTERBURY FISH AND GAME COUNCIL Dated 17 th day of April I prepared a first statement of evidence dated 6 March 2009, in respect of Fish and Game's application for a Water Conservation Order on the Hurunui. I confirm the detail of my experience and qualifications set out therein. 2. In this statement of evidence I set out my comments in rebuttal in respect of the evidence of: Bruce Norrie, for Hurunui Water Project and Mainpower Ltd. Richard Allibone for Amuri Irrigation Company Ltd ("AIC"). Terence Heiler for Amuri irrigation Company Ltd. Philip Mitchell for Meridian Energy Ltd. Bruce Norrie, evidence dated 23 March At paragraph 20 Mr Norrie states that Pahau River contains..a very valuable fishery which no doubt supplies many fish to the Hurunui system.. due to the augmentation of river flows through the discharge of the Amuri Irrigation Company s Balmoral scheme (AIC). Mr Norrie also suggests that the flow augmentation of the Waitohi River through the similar irrigation scheme would result in similar improvement. 4. I disagree with the above statements as Pahau River does not feature prominently in the National Angler Surveys of 1995, 2001 and 2008 as valuable fishing water. Fish & Game experience with this river is that it provides poor trout habitat due to the poor water quality resulting from stock access to the river and generally poor water quality due to the intensive agriculture in its catchment and the discharge from the Balmoral irrigation scheme (see rebuttal evidence by Dr Young). Fish and Game conducted an MAB V1:pam

2 electro-fishing survey of the river in 2008 in an attempt to collect juvenile and post spawning adult fish for a study in the migration patterns of trout in the Hurunui River system (Tobias and Bickel, 2009; reported by Dr Young, evidence dated 6 March 2009). The survey revealed very low numbers of fish with only four fish collected (2 juvenile and 2 small trout) in more than 2 km of the river. The Waitohi River survey resulted in ten juvenile and three adult post spawning fish in less than a kilometre of water. I do not believe that augmentation of flow in the Waitohi River through the irrigation scheme discharge would result in an improved fishery due to the potential intensified land use in its catchment and inherently low water quality discharge at the end of an irrigation scheme. Richard Allibone, evidence dated 23 March At paragraph 44 Mr Allibone makes a simplified assumption on the juvenile Brown trout growth and distribution in the Hurunui River system based on the paper of Hayes (1988) on the trout life cycle in the tributary of Lake Alexandrina, Mackenzie basin. Mr Allibone states that a small proportion of juvenile fish (only 24%) are likely to disperse to the mainstem after hatching. The statement was made in the context of questioning whether or not fry will have grown to sufficient size by the time they reach the Amuri intake to be prevented from entering the intake by a 5mm screen rather than the specifications I am recommending. 6. A number of studies on the Brown trout in other braided Canterbury rivers (Fox et al., 2003; Glova and Boubee, 2002; Greynoth et al, 2003, as summarised in my first statement of evidence) indicate that there is a significant migration of juvenile trout from their natal streams to the mainstem in search of rearing habitat. Juvenile fish as small as 30 mm are present in the lower reaches of the Rakaia River for at least three moths a year and fish smaller that 50 mm are present for up to five months (Jamieson et al., 2007; as presented in Table 1 of my first statement of evidence). A 5mm mesh size and approach velocities higher than proposed 0.12 m/s as mentioned by Mr Allibone (in paragraphs 43, 44 and 46) are not likely to provide sufficient protection to fish of that size. Fish & Game collected juvenile trout in the mainstem of the Hurunui River at SH7 and SH1 sites in 2003 for the trout growth study (Hayes and Quarterman 2003). MAB V1:pam Page 2 of 11

3 7. In the paragraph 51 Mr Allibone refers to my evidence as providing justification for fish screen parameters in general terms only and states that the evidence does not address current issues with the existing AIC Hurunui take. 8. In my evidence I intended to provide the Panel with the general justification for the proposed fish screen criteria in relation to the trout and salmon population in the Hurunui River. I did not address the issues with the AIC take due to the Applicants' intention not to instigate changes to consent conditions for the existing takes until their consents are due for renewal, in 2033 for AIC take (see paragraph 138 of the Hurunui River Water Conservation Order Application). I will comment on the potential issues with the current AIC take further in my rebuttal. 9. In paragraph 52 Mr Allibone states that in his evidence Mr Williamson claims there are no issues with the AIC Hurunui take. 10. I was not privy to Mr Williamson's evidence (it was not available while producing this rebuttal) but based on my experience with the other AIC take from the Waiau River, of very similar design to the Balmoral intake (5mm mesh as well, but larger volume intake with four instead of two drum screens), operated by the AIC it is likely that there are issues with juvenile trout and salmon entrainment at the Balmoral intake. In the past Fish & Game attempted salvage operations at the Balmoral scheme but it was not regarded feasible (see supplementary and rebuttal evidence by Mr Ross). Annual salvage operations are conducted at the AIC s Waiau scheme. Also Mr Heiler in his evidence mentions salvage of trout that happens annually in the Balmoral take settlement pond. 11. In paragraph 52 Mr Allibone also states that in 1997, during AIC take re-consenting, Fish & Game was satisfied with the operation of the Balmoral fish screen and that a number of monitoring reports shows compliance with consent conditions. In paragraph 53 Mr Allibone states that compliance with consent conditions equals the effective exclusion of trout fry from the intake. 12. Fish & Game's understanding of issues associated with fish screening have evolved significantly since 1997 when Balmoral intake was re-consented. In 2004 Fish & Game conducted a review of fish screens in the North Canterbury region (Hardy, 2004) and approached Environment Canterbury with serious concerns that this review raised. As a result Environment Canterbury formed a Fish Screen Working MAB V1:pam Page 3 of 11

4 Party (FSWP) and instigated work on the review and update of fish screen criteria for water takes in Canterbury. I strongly disagree with Mr Allibone s statement that compliance with consent conditions from the mid 90s results in a sufficient level of protection for juvenile sports fish that Fish & Game seeks nowadays. Terence Heiler, evidence dated 23 March In paragraph 13 Mr Heiler states that the fish screen criteria as proposed by the Applicant have their origin in the document Fish screening: good practice guidelines for Canterbury" (Jamieson et al, 2007). 14. The proposed fish screen criteria are based on Fish & Game research into the fish screening that I conducted as a part of the Fish Screen Working Party (Bejakovich 2006). The findings of the study were used to formulate the Applicants proposed fish screening criteria. An independent study undertaken by NIWA (Jamieson et al, 2007) for the FSWP reinforced the recommendations of the Fish & Game research in October 2007 (Hurunui WCO application was lodged in August 2007). 15. In paragraph 30 Mr Heiler wrongly states that Fish and Game proposed fish screen parameters for screen aperture were based just on the measurement of the width of the head of juvenile fish of various lengths (a surrogate for age). 16. Fish & Game proposed fish screen criteria for screening material aperture size in this Application and in the document produced for FSWP were based on the actual experimental data on live sports fish as well as numerous results of comprehensive testing of actual fish screening facilities overseas, mostly in USA (see my first statement of evidence, Appendix 1 (Bejakovich, 2006), pages 11-12, for summary of results) and not on juvenile fish head measurements. Data on fish screening for juvenile salmonid species from North American literature was most readily available as the current guidelines were implemented there in mid 90s to protect the very sports fish species we look to protect in Canterbury, Chinook salmon and various trout species. The proposed parameters and the Fish & Game document were peer reviewed and endorsed by the US fish screening experts. Mr Heiler has participated for three years in the FSWP process and has all the information I have referred to above. MAB V1:pam Page 4 of 11

5 17. In paragraphs 32 and 33 Mr Heiler states that he is not convinced that the 100% exclusion (of sports juvenile fish) that Fish & Game seek is justified based on the available information. 18. Fish & Game have sought 100% (or as close as practically possible) protection for juvenile sport fish at water takes due to the unprecedented deterioration of the sports fish resource (Mr Bell, evidence dated 6 March 2009; Mr Ross, supplementary evidence) in Canterbury. The potential cumulative effects that water takes have in combination with the deteriorating water quality, land use intensification and climate change effects could easily lead to collapse of the sport fishery. Even the best designed fish screen facilities are not 100% effective in protection of juvenile sports fish species. If proposed fish screen criteria are adopted Fish & Game believe that sufficient protection of the resource will be achieved. In the case of the outstanding fishery of the Hurunui River I see the 100% effectiveness of any future developed fish screen as appropriate to ensure continuation of this fishery resource for future. 19. In paragraph 34 Mr Heiler states that there are also practical consequences with small aperture screens in the NZ situation and lists blockages, the strength of the screens and concludes that adoption of proposed criteria would compromise some existing intakes. 20. Although the Applicant is not seeking to impose proposed fish screen criteria to the existing intakes on the Hurunui River until they become due for re-consenting I will comment on the issue of small aperture size and blockages. There is no experience in Canterbury with fish screen with the aperture size smaller than 5 mm. In the past I have asked leading US experts on fish screen design about the potential effects of smaller aperture size on fish screen operations following a similar statement by the engineers representing irrigation companies (in discussions in respect of an Environment Court appeal between Fish & Game North Canterbury and Ngai Tahu Ltd) regarding proposed Waimakariri River water take. I include Mr Nordlund s 1 response in full ( dated 8 March 2007): The reason why a small mesh opening does not restrict flow is because of three other criteria (approach and sweep velocity and effective maintenance). If the screen is kept clean by an effective screen cleaning system, and if the approach velocity (Va 1 Bryan Nordlund, National Marine Fisheries Service, is in charge of the bioengineering group that develops the official positions on fish screening criteria. MAB V1:pam Page 5 of 11

6 - perpendicular to the screen mesh) is kept low and uniform (we use max Va of 0.4 ft/s 0,12 ms-1), and if the screen material has at least 27% open area, very little head loss will occur across the screen - it should be less than 1/4 inch. If you double the opening size and keep the percent of open area the same, the head loss and flow will not change much. For example, I've calculated the flow difference between a 4-12 mesh (33.4% open area with inch square opening 3.7 mm) versus a 6-14 mesh (27% open area with inch square opening 2.2 mm). The calculation showed that the flow went from 30 cfs (cubic feet per second 0,027 m3s-1) with the inch opening, to cfs with the inch opening - not even within flow measurement capabilities of most instruments. Similarly, a study carried out by Stefan and Fu at the St Anthony Falls Lab, USA, showed very little difference in head loss coefficients between these two meshes, even though the openings in the 6-14 mesh were 60% smaller than the 4-12 mesh. The percent open area is the key. Any debris accumulation on the screen opening will reduce open area and increase head loss, and that's what irrigators typically worry about. However, since we require (NOAA fish screen guidelines) continuous cleaning (such as occurs with rotating drum screens), this is not really an issue so long as the screen is in good working order. 21. Similarly Mr Bates 2, (in dated 1 April 2007) comments, when I asked him to review similar statement to that made by Mr Heiler on small aperture size (5mm v smaller openings): "They (MWH and T&T) conclude that the operation and maintenance will be challenging if the aperture is less than 5 mm. They provide no information to justify that statement. What debris or sediment will accumulate with the smaller bar openings that won t with the 5 mm openings? What will be the effect on backwash timing and real effect on maintenance? 22. I had discussions with other US experts (Mr Williams, US NMFS, and Mr Dorratcague, MWH Global personal communication) during the International Ecohydrology Conference held in Christchurch in 2007 who all shared the same view that there was little justification for the concerns that smaller aperture size will lead to difficulties in fish screen operation compared to a larger aperture size. They commented that similar concerns of fish screen operators in US proved to be unjustified after new regulations were implemented in US in Ken Bates is an environmental consultant in US formerly employed as an engineer with US National Marine Fisheries Service. Mr Bates have done the original research(bates 1988; Bates and Fuller, 1992) that led to implementation of the contemporary fish screen criteria in US. MAB V1:pam Page 6 of 11

7 23. In paragraph 36 Mr Heiler comments on the issues of different nature of Canterbury rivers and their high sweep velocity and approach conditions as well as generally higher velocity in many New Zealand rivers than in the international studies. 24. I do not understand how the conclusion that the velocity conditions of the New Zealand rivers were very different to that of the rivers in the international studies was arrived at, as the statement is not supported by examples in Mr Heiler's evidence or in his views presented to the FSWP during my participation. In my experience with the extensively reviewed literature, fish screen facilities overseas have been developed in a variety of conditions and waterway types. Also, the issue of approach and sweep velocity is related to the design of the intake canal and hydrological condition in it, as well as the open area of the screen (approach velocity) and angle of the screen to the incoming flow (sweep velocity). Due to the nature of the lower Hurunui River it is likely that any intake would be designed away from the river just like the AIC Balmoral intake (1.5 km canal leading to the fish screen). 25. In paragraph 39 Mr Heiler states that the inclusion of fixed and conservative fish screen aperture standard into the WCO is not justified. In his opinion that would set a precedent and flow into the Regional Plan and prevent further effort to look for innovative solutions appropriate in New Zealand conditions. 26. I strongly believe that the proposed fish screen criteria (including aperture size) are justified as they are likely to provide very high level of juvenile sports fish protection for water takes developed at the Hurunui River. There are currently no proven innovative solutions and Fish & Game s experience with some innovative designs are much less than satisfactory. The outstanding fishing resource in the Hurunui River is worthy of the highest level of protection available. 27. In the paragraphs 43 and 44 Mr Heiler explains the reasons for Fish & Game's proposed sweep velocity criterion and concludes that the criterion was based on the US requirements where intakes are located in dead water that has no intrinsic current. 28. I can confirm that the proposed criteria are based on the extensive literature review and review of the relevance for Canterbury conditions and existing intakes. I do not understand the references to "dead water" and "intrinsic current" but I want to reiterate the necessity for the sweep velocity and approach velocity criteria to be met, MAB V1:pam Page 7 of 11

8 together with other requirements, to ensure effective protection of juvenile sports fish. As pointed out above, approach and sweep velocity are related to the design of the intake structure and not the velocity of the water in the waterway from which water is taken. 29. In paragraph 66 Mr Heiler states that the AIC Balmoral intake does not comply with the proposed fish screen criteria based on his analysis in paragraphs In paragraph 67 the statement is made that to comply a doubling of the capacity and hence duplication of the existing facility would be required". In Mr Heiler s view that would present a considerable difficulty from an engineering perspective and he estimates that compliance work would cost at least $400, I agree with Mr Heiler that the AIC Balmoral intake does not comply with the proposed criteria but I repeat that the Applicants clearly state in paragraph 138 of the Water Conservation Order Application that there is no intention of imposing proposed fish screen criteria to the currently consented water takes until their consent renewals are due (in 2033 for the Amuri Irrigation Company Ltd Balmoral intake). I disagree with Mr Heiler s statement that to comply the facility would need to double the capacity. To comply with the approach velocity criterion the facility would need to double the open area of the fish screen. When current AIC intake resource consent expires and a new consent is applied for (in 2033) the cost of compliance, based on Mr Heiler s estimate ($400,000), would be less than $70 per ha irrigable land (cca 6000 ha) or less than $2 per ha per year (based on the current 35 year consent period) in current value. 31. In paragraphs Mr Heiler describes and discusses sweep velocity at the AIC Balmoral intake and states that sweep velocity conditions will develop and given the generous escape routes the sweep velocity is issue of no importance on the facility. 32. I am familiar with the AIC Balmoral intake. I visited the facility recently. I agree that sweep velocity might be sufficient for the half of the fish screen but another half of the screen is perpendicular to the incoming flow. That, in combination with higher than recommended approach velocity and larger aperture size is likely to provide less than the required protection for juvenile sports fish at the facility. Still, the Applicant does not seek compliance with the proposed fish screen criteria until the scheme is due for the consent renewal in MAB V1:pam Page 8 of 11

9 33. In paragraph 74 Mr Heiler describes the characteristics of the Balmoral intake and concludes that it effectively excludes fish from entering the scheme. 34. Based on my expertise and experience with the Waiau part of the AIC scheme (larger intake but same design with four drum screens vs two drum screens at Balmoral), where I took part in fish salvage operations I can not support the above statement. A combination of insufficient sweep velocity (on at least half of the screen face), higher than required approach velocity and larger aperture size is likely to provide less than currently required protection for juvenile sports fish in the Hurunui River. 35. In paragraph 77 Mr Heiler concludes that the Balmoral intake arrangements are an example of sound design, construction and maintenance. 36. I concur with Mr Heiler that the Balmoral intake is an example of sound design for the time it was built but fish screening design criteria that are needed to ensure high level of protection for the juvenile sports fish have evolved during the several decades since the scheme was built. The need for protection of the sports fish resource has became more apparent and critical in recent times as well. Philip Mitchell evidence dated 31 March In paragraph 83 Dr Mitchell states that A prescriptive one size fits all standard prevents project specific design flexibility, and would also constrain new fish screening design and technological innovation. 38. The Applicant proposed minimum fish screen criteria proposed are required to provide a high level of protection for the juvenile sports fish of the nationally outstanding Hurunui River fishery. Overseas, the statutory agencies responsible for salmonid fishery management have found the proposed criteria as the only appropriate tools in protection of sports fish at water intakes. Other innovative solutions have yet to prove their effectiveness. The fish screen proposed criteria do not prevent site specific design flexibility. 39. In paragraph 84 Dr Mitchell states A purposive standard which firmly states that appropriate fish screening representative of best practice that prohibits fish from entering the intake would in my opinion be more appropriate. Suggested wording is MAB V1:pam Page 9 of 11

10 as follows: All intakes associated with the taking or diversion of water shall be designed, constructed and maintained to prevent the entrapment of fish. " 40. A similar less prescriptive wording with no specific fish screen design criteria was tried in the past and has resulted in designs that did prevent entrapment of fish but not the safe return of fish to the mainstem of the river. A number of existing operating fish screens in Canterbury (an example from the lower Rakaia River in Pictures 1 and 2) that are detrimental to the juvenile sports fish (for examples see Hardy, 2004) are compliant with the existing consent conditions (Bonnett 2004). The wording of these consents is consistent with the wording proposed by Dr Mitchell. I strongly believe that the Applicant s proposed fish screen criteria are bottom line requirements to protect juvenile sports fish at water intakes. References Bates, K (1988). Screen Criteria for Juvenile Salmon. Washington State Department of Fisheries. Bates, K. and Fuller, R. (1992). Salmon Fry Screen Mesh Study. State of Washington Department of Fisheries. Fox, S., Unwin, M. J. and Jellyman, D. (2003). The Migration of Brown Trout in the Rakaia River System. Report to Fish and Game. NIWA, Christchurch. Glova, G. and Boubée, J. (2002). Project Aqua: Summary of Screening Mitigation Considerations for Protection of Migrant Fish of the Lower Waitaki River. Report for Meridian Energy Ltd. NIWA, Christchurch Graynoth, E., J, G., Hayes, J. and Bonnett, M. (2003). Project Aqua: Environmental Study Aquatic Ecosystems: Salmon and Trout. Report for Meridian Energy Ltd. NIWA, Christchurch. Hayes, J. & A.J. Quarterman (2003). Modelling Trout Growth in the Hurunui River. Report prepared for Fish & Game New Zealand: North Canterbury Region. Nelson: Cawthron Institute. D Bejakovich April 2009 MAB V1:pam Page 10 of 11

11 Picture 1. Fish screen compliant with resource consent conditions excluding sports fish from the irrigation scheme. Picture 2. By pass leading nowhere. MAB V1:pam Page 11 of 11