peer review report 2 on economic effects of a reservoir re operation policy in the rio grande bravo for integrated human and environmental water management

Journal of Hydrology: Regional Studies (2017) 163–165 Contents lists available at ScienceDirect Journal of Hydrology: Regional Studies journal homepage: www.elsevier.com/locate/ejrh Peer Review Report Peer review report on “Economic Effects of a Reservoir Re-operation Policy in the Rio Grande/Bravo for Integrated Human and Environmental Water Management” Original Submission 1.1 Recommendation Major Revision Comments to Author Review of Ortiz-Partida et al ‘Economic Effects of Reservoir Re-operation Policy in the Rio Grande/Bravo for Integrated Human and Environmental Water Management’ David Dean April 15, 2016 2.1 General Comments Ortiz-Partida et al., analyze the economic effects of a potential environmental flow (EF) scenario for the Rio Grande/Bravo that was proposed by Lane et al., 2014 The proposed EF policy aims to restructure the operation of Luis L Leon dam on the Rio Conchos, in order to better support the native aquatic and riparian ecosystem of the RGB Benefits to the native ecosystem include the maintenance of Rio Grande silvery minnow habitat, and the limiting of channel narrowing The economic effects of this proposed policy are analyzed in reference to irrigated agriculture, river recreation, flood control/damages, and environmental factors This Journal of Hydrology:Regional Studies is a suitable outlet for this topic This manuscript is important for describing a vision, and analyzing the economic costs of one environmental flow scenario for the RGB in the Big Bend region Water management and ecosystem health have generally been at odds for this portion of the RGB, and this manuscript illustrates that certain flow scenarios may benefit both the economy and the environment This finding has the potential to shift the current thinking of water management, where benefits to the economy and the environment are mutually exclusive Although this manuscript has a strong premise, and potentially binational impact, I believe it falls short on a few levels, and major revisions should be required before publication By incorporating the below comments, I believe this manuscript can make a strong contribution to water management and policy First, the proposed EF policy is not adequately explained Even though the proposed EF policy is described extensively in other manuscripts (Lane et al., 2015; Sandoval-Solis and McKinney, 2014), this manuscript should be able to stand on its own To accomplish this, afigure that illustrates reservoir rules for the EF policy should be included, along with a schematic of the effects that the proposed monthly EFs have on monthly streamflow, with an underlying justification for those EF policy rules (something similar to Lane etal., 2014 Fig 3) The reader is left in the dark as to what the hydrology of the RGB actually DOI of the original article:http://dx.doi.org/10.1016/j.ejrh.2016.08.004 2214-5818/$ – see front matter http://dx.doi.org/10.1016/j.ejrh.2016.12.047 164 Peer Review Report / Journal of Hydrology: Regional Studies (2017) 163–165 looks like, and how the baseline and EF policies differ for the past 55 years Another useful figure could show the entire hydrograph of daily flows, with both the monthly baseline and EF flow volumes superimposed on the daily hydrograph The hydrograph can be used to illustrate periods of flash flooding, and periods of long duration dam releases, and/or floods produced by tropical storms The reader would then be informed as to how the daily hydrograph, and the different hydrologic aspects that compose that hydrograph are translated into monthly flow volumes under the baseline and EF flow scenarios This could be used as a main figure for the results Additionally, the Discussion is lacking The Discussion briefly describes the results as pertaining to each individual economic aspect under consideration However, there is no discussion regarding whether or not the proposed EF policy would actually be successful at achieving what it was designed to do, which is environmental based (according to Lane etal., 2015) One angle to improve on this would be to discuss how the proposed EF policy could be incorporated into an adaptive management scheme whereby the environmental effects of the EF policy are analyzed over a specific time period to gage success of the measures The EFs were designed based on the IHA metrics produced in the BBEST 2012 report, however, there is quite a bit of uncertainty regarding the IHA metrics within that report Thus, framing the EFs within an adaptive management context allows for the revision of the EF guidelines which have potential feedbacks into the economics As it currently reads, the manuscript is too deterministic (i.e If EFs are implemented, the environment will be rehabilitated, and the economics will generally improve) However, there is no talk about how these measures are uncertain, and how these things may change as more is learned, both environmentally and economically It is ok if this angle is not pursued, however, the discussion needs to be strengthened given that this proposed reservoir re-operation scheme has the potential to be of impact at the binational level Specific Comments: (note, I am not sure if the journal requires line numbering, but it is difficult to comment/edit without them Authors should consider providing line numbers in next submission) Page 2, line 3: delete “nowadays” Page 2, middle paragraph: delete semicolon after the word “activities” Page 3, 1st full paragraph: revise to read “Third, flood management, considering the protection of Presidio and Ojinaga cites from floods” Page 4, 1st paragraph: delete “the repetition of” Page 5, end of Section 2.1.1: consider revising to read " (i.e more water allocated than available for use)" Page 5, 2nd sentence of 2.1.2: I am surprised this number is not larger than 300,000 Page 5, 2nd sentance of 2.1.2: consider revising to read "(NPS, 2015); in 2011, visitors spent over 16 million dollars” Page 6, 3rd sentence of 2.1.3: At times the Rio Conchos can supply nearly all of the total stream flow to the RGB below its confluence This sentence should be edited reflect this Not sure where the 20x factor came from Page 6, 4th sentence of 2.1.3: consider revising to read “Major historic floods have resulted from extended periods of steady rainfall associated with tropical storms and hurricanes, although ." Page 7, 2nd sentence: The native silvery minnow population has not only been dramatically reduced, but it was actually extirpated from the reach This sentence should be edited to reflect extirpation, not simple reduction The 2nd sentence of the following paragraph should be edited to read “Its disappearance appears to be related to channel modification ." because the exact cause has not been determined Page 7, 4th sentence of same paragraph: revise to read “In contrast, tamarisk and arundo donax are invasive riparian plants prevalent in the RGB that can reduce water availability and quality, and may outcompete native riparian species under certain hydrologic scenarios” There are hydrologic scenarios that discourage the proliferation of these non-native species Page 7, Delete last sentence before “Rationale”: Page 7, 3rd sentence of “Rationale”: state that “Some of the negative effects can potentially be reversed ." and cite Dean et al., 2016 at the end of sentence Dean, D J., D J Topping, J C Schmidt, R E Griffiths, and T A Sabol (2016), Sediment supply versus local hydraulic controls on sediment transport and storage in a river with large sediment loads, J Geophys Res Earth Surf., 121, http://dx.doi.org/10.1002/2015JF003436 Page 8, Methods: it seems that the Methods section includes both methods and results Consider reorganizing such that the Methods and Results are separated into their own sections, or revise the heading of Section to include both Methods and Results Page 8, paragraphs and 2: Strikes me that stating the cost at $.108 million per mcm is a strange way to present the units (million per million?) Maybe this is the unit requested by journal, but consider revising to $108,000 per mcm Page 8, last paragraph, 2nd sentence: change “experience” to “experiences” Equation 1: Clarify how water demand is calculated Page 10, last paragraph 3.1: This points back to explaining how the EFs impact the hydrograph, as I state at the beginning of this review In this instance, it appears that base flows would be reduced at certain times of the year, while intermediate flows would increase at other times The reader needs to be explained how the proposed EFs generally impact the hydrology in a more clear and concise manner, as well as what the goals of the EFs are specifically (e.g high flow pulses in late summer/fall to convey sediment and prevent channel narrowing, high flows in spring to queue spawning of silvery minnow, etc.) Page 11, paragraph after Fig 4: The logarithmic relation should be included as a figure so the reader can see the shape of the function, and further understand this relation Peer Review Report / Journal of Hydrology: Regional Studies (2017) 163–165 165 Page 13, section 3.3: state that recreation benefits “slightly decrease” instead of just “decrease” End of same paragraph: Clarify point (3), under the EF scenario, you state the probability of flood related damage goes down, however, there are a number of flood events that will be greater than the baseline, potentially offsetting some of the cost savings associated with the lower probability Page 14 1st sentence of last paragraph: I don’t understand this first sentence because agriculture is the largest benefactor to the EF policy Fig 3: These data points are not intrinsically linked to each other, and therefore, should be plotted as a scatter plot, not as a line plot A linear regression, should then be fit to the data points First revision 3.1 Recommendation Minor Revision Comments to the author Review of Ortiz-Partida et al ‘Economic Effects of Reservoir Re-operation Policy in the Rio Grande/Bravo for Integrated Human and Environmental Water Management’ David Dean April 15, 2016 General Comments: Ortiz-Partida et al., made a substantial effort at improving the manuscript referenced above They have addressed most of my comments sufficiently, and the new requested figures have the effect that I had hoped I had a number of minor edits and comments, that are listed below, and I’m sure the authors can address these quickly Based on these comments, I am recommending minor revisions Page 2, line 2: insert “for” after searching Page 5, line 23 − (Eflowstnormat) should be (Eflowstnormal) Page 6, Fig caption In the caption, describe the changes the take place between the Baseline and EF policy in B To me, it looks increases in storage are capped, and released as EFs, which causes the purple “top of conservation” capacity line to fluctuate Please either describe in the text, or in the caption Also, I not see Fig referenced in the text Page 8, lines 4–9, flooding proxy?????? Page 8, line 22, edit to read, ";even though the cause of its extirpation has not been determined, substantial geomorphic changes occurred, and key habitats of the silvery minnow were lost (Dean and Schmidt, 2011) Page 11, line 28 Is this the “raftable” streamflow limit? Or the “canoeable” stream flow limit The raftable limit is considerably higher than the canoeable limit Page 13, lines 18–19, edit to read “Monthly flow volumes show that under the baseline policy, ." Page 15, lines 28–31 Increased water availability would only occur if nonnatives are killed, and those surfaces remain bare This is a possibility under the EF scenario, whereby erosion may create additional bare substrates However, without sufficient flood disturbance, another type of vegetation is likely to recolonize those bare surfaces, and water savings would likely be nonexistent or negligible A sentence or two in this section, or in the discussion, would be helpful to clarify these potential dynamics Page 16, line 14, “flood” should be “floods” Page 17, line 26, change rising to increasing Page 18, line 15 Change “dragging” to “adopting” or something similar Page 18, lines 25 and 26, change “down-ramp” to “flow recession” Research Hydrologist David J Dean USGS, SBSC GCMRC, 2255 N Gemini Dr, Flagstaff, AZ 86001, United States ... author Review of Ortiz-Partida et al ? ?Economic Effects of Reservoir Re- operation Policy in the Rio Grande/ Bravo for Integrated Human and Environmental Water Management? ?? David Dean April 15, 20 16... channel modification ." because the exact cause has not been determined Page 7, 4th sentence of same paragraph: revise to read ? ?In contrast, tamarisk and arundo donax are invasive riparian plants... based on the IHA metrics produced in the BBEST 20 12 report, however, there is quite a bit of uncertainty regarding the IHA metrics within that report Thus, framing the EFs within an adaptive management