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10/13/2011 Backup Documents lO-\~-l\ J k VV\ Szrrr - t,. cA-c. ~4+~Y C v~'\~ e\l -...!.L~ ~ Lu Or I ~'1 ..0-\- c; . u V'.:>\_ t= ( Uf l ~ '"' When considering the establishment of nutrient criteria for an estuary the goal should be to establish nutrient criteria that are protective during periods when the estuary and coastal ecosystems are at their most vulnerable to nutrient enrichment and to protect the designated use, which in the case of Clam Bay is defined as Class II waters. The objective should be to restore the original ecological integrity to the best extent possible. Since estuaries exhibit a high degree if individuality relative to nutrient susceptibility, it is necessary to ascertain the general range of algal biomass that leads to impairment (hypoxia) at a known level of enrichment for each estuary. This type of assessment requires many years of measurement and observation. As data for many estuaries are not available to calculate these types of ranges, it becomes necessary to rely on historical data, local knowledge and technical workgroups where the scientific expertise of local and regional experts can be vetted to develop criteria. This should be viewed as a stop- gap measure until one can determine the range of algal biomass that leads to impairment at a known level of enrichment for each estuary. Once established, nutrient criteria should periodically assessed and refined as conditions dictate, since the standard set could still allow for continual deterioration of water quality or the biological components within an estuary or both. An anti-degredation policy attached to the document that promotes continually improving conditions. Estuaries such as Clam Bay that supply nutrients to relatively static coastal waters should have more stringent standards not only to protect the estuary but the coastal shelf waters that are often used for swimming and fishing. General Comments on the Atkins Proposed Criteria 1. In the Atkins report the statement is made that nutrient concentrations are inversely related to salinity in Hillsborough River, Sarasota Bay, Charlotte Harbor, EsteroBay Wetlands. Given these systems larger spatial extent it is logical that these systems receive a much higher point source, volume and flow of freshwater from rivers and streams that connect to these areas (Figure 1). Clam Bay on the otherhand, given its much smaller spatial extent receives less freshwater input (i.e. rain and stormwater runoff) with little point source discharges (no rivers or streams and less outflows). Therefore, logic would suggest that the duration and frequency of salinity and conductivity decreases during the wet season should be less dramatic than the northern systems previously mentioned (barring extreme weather events) (Figures 2 and 3). Given the premise that decreased salinity or conductivity coincides with increased nutrient (from the freshwater discharges), Clam Bay should have less of an increase in comparison to our northern neighbors, given that the pollution loads should be much less in this area (Table 1). Additionally, it seems that if you "normalize" salinity or conductivity values you are accommodating higher nutrient levels if flows are increased by natural causes which would be okay, but also by anthropogenic causes which would not be okay. Therefore given these differences, would it be more logical to not only use Clam Bay's data set to develop nutrient and salinity relationships, but develop its own best fit linear equation instead of plugging Clam Bay conductivity values into an Estero bay derived equations to determine site specific criteria? A method would also have to be developed to prevent the possibility of having the criteria reflective of higher anthropogenic flows, which decrease salinity and conductivity and thus potentially increase nutrient levels above what is desirable for a healthy estuary. Regarding the equation referred to in the above paragraph for Estero Bay (shown below). I assumed that Atkins used the same constant values (shown below in bold) for Estero Bay and Clam Bay? TN (mg/l) = 1.30908 - 0.00001664.14 (conductivity in Ilm) Same goes for the TP calculated standard The physical classification of estuarine or coastal waters is scale sensitive (Giller et. al 1994) and as such generalizations and predictions of nutrient enrichment effects may not be as useful, in contrast to findings in rivers and streams. Classification based on salinity gradients, circulation patterns, depth and flushing within larger estuarine and coastal systems may prove useful, especially in correlating different biological communities at risk to nutrient overenrichment, but in small-scale estuaries such as Clam Bay relationships may not be as clear (EP A Nutrient and Algal Criteria Development Chapter 7 in Nutrient Criteria - Estuarine and Coastal Waters). 2. The Atkins report states that the Clam Bay estuary is co-limited by Nand P, whereas FDEP is basing all of its criteria in the Collier region on an assumption of an N-limited system. Question: Is the premise that clam bay is co-limited based on the 2 years of data collected over a draught period? If so this is not enough data to support such an assumption which could affect how you are setting criteria. Question: Is the system n-limited during the summer as in the case of most of our estuaries? The Atkins report states that the data used for the comparison between Clam Bay and Estero Bay Wetlands were from "the IWR Run 42 and Collier County for the period of record". Question: Clarify what is meant by period of record? If this refers to the years 2009-2011 then the interpretation of the results could represent what is typical today during a draught period. This would create limitations on the resulting criteria derived from this particular data set as analysis occurred over a drought period and may not be a good representation of the system over different climatic conditions. 3. There is often a strong relationship between seasonal values - this does not seem to be taken into account - rather the average is used, which in the case of Florida estuaries, show strong seasonal responses based upon local climatic conditions that can skew the results and not be reflective of natural conditions. 4. Charlotte Harbor identified that the standard for chlorophyll of 11 Ilg/l was not fully supportive of seagrass in the deeper edge for most of the estuary segments and a more rigorous standard was recommended. Additionally FDEP is proposing more rigorous standards than those currently being discussed for Clam Bay (albeit they are not standardized for salinity) these standards are currently being proposed for the Ten Thousand Islands, Rookery Bay and other Collier inshore areas (CB is not included). FDEP Ranges proposed for these areas as follows in comparison to Atkins proposed criteria. Site TP (mg/I) TN (mg/I) Chi A (ug/l) Clam Bay 0.057 0.6 or 0.81 * 11 Estero Bay 0.07 0.63 5.9 Collier Estuarine Areas 0.015 to 0.054 0.242 to 0.39 1.36 to 5.86 * Differences between reports and technical notes. There seems to be a lot of differences in criteria values and approaches and there needs to be more time spent vetting all materials and methods by a working group made up of Collier County and its Consultants, Environmental Groups, Regulatory Groups and representatives from local interested parties so that there is not such a wide discrepancy between criteria as shown above. There is plenty of time to further evaluate this proposal since Clam Bay is not in the areas now being evaluated by FDEP for estuarine waterways. Rather it will be included in tidal systems whose standards will be developed after the freshwater and estuarine are completed, which could be years down the road. There is also a lot of controversy that needs to be settled on the overall question of nutrient criteria prior to making criteria for Clam Bay. 5. In so far as the duration and magnitude of non-compliance of criteria, investigations should be triggered so that the duration and magnitude of an out of compliance situation does not affect the distribution, abundance, and recruitment of key species in particular. Causal variables TN TP and response variables algal biomass, chI a for phytoplankton AFOW (ash free dry mass) for macroalgae; water clarity (secchi and depth); and dissolved oxygen for hypoxia are typically evaluated when proposing standards. Failure to meet any of the causal criteria should reflect in one or more of the response variables. However there should be contingencies to respond if one or more of the response variables are indicative of a problem then there has to be an investigation to determine whether or not the criteria are not responsive enough to indicate change or problems. Other Questions 1. What are the p values between regression analysis: i.e. chI A and secchi; tn and cond; tp and cond, etc? 2. What are the relationships between tn, chI a , do, turbidity, water clarity (secchi) and also to tp (show analysis or graphs). And the differences between using tn and tp versus using inorganic and organic nand p analysis. 3. Has analysis been done to ensure proposed nutrient criteria supportive of current State D.O. water quality standards? Concluding Comments: Hold the line strategy suggests that there is no intention of improving the health of the estuary, when clearly we can. Make sure that this document does not give the impression that this is the best we can do for the health of the estuary. This plan is not flexible enough as it does not state that modifications to the plan will occur as either the science improves or as evidence suggests that the set specific criteria are not enough to keep the health of the estuary from becoming compromised. The criteria should prove that the standards set provide for the protection and propagation for all stages of life cycles of fish, shellfish, benthic organisms, habitats, etc. that the estuary historically supported (within realistic attainable goals) that at the very least do not allow for any deterioration or decrease in growth rates and vitality. The data should be used to ascertain what levels are needed to attain certain biological endpoints that would indicate restoration of the bay's biological health. Figure 1: Estero Bay Watershed Source: Schmid, l.R., G.G. Buckner II, E.C. Milbrandt, and D.W. Ceilley. 2006b. Ecological calibration of Estero Bay basins. Final Report to the Environmental Protection Agency Gulf of Mexico Program Office. 103 pp. Hendry County N A 024 , 6 Kilometers Figures 2 and 3. Examples of Salinity Fluctuations at Estero Bay tributary sampling sites during the (a) early dry season (2005) and (b) early wet season sampling events (2004). Mixohaline sites are identified on each graph. ERI, ER2 and ER3 = Estero River; HCI and HC2 = Hendry Creek; IR2and IR3 = Imperial River; MCl= Mullet Creek; and SC2 =Spring Creek. Source: Schmid, J.R., G.G. Buckner 11, E.C. Milbrandt, and D.W. Ceilley. 2006b. Ecological calibration of Estero Bay basins. Final Report to the Environmental Protection Agency Gulf of Mexico Program Office. 103 pp 20 MC1 15 HC2 SC2 - ER3 15.. HC1 .8: IR3 ~ 10 c: 1ii C/) 5 ER2 o IR2 ER1 1 2 (b) Early wet season sampling events 3 L..,J -- 5 HC2 20 if 15 S ~ .c ~ 10 MC ER3 HC1 IR3 o E~2& ER1 2 (a) Early dry season sampling events 3 Table I: Area-weighted values total nitrogen load ([lbs/yr]/acre), total phosphorus load ([lbs/yr]/acre), and total suspended solids (TSS; [lbs/yr]/acre) from the Estero Bay Watershed Assessment (PBS&J, 1999) for sample sites and corresponding tertiary basins. Source: PBS&J, Inc. 2000. Estero Bay Watershed Assessment Report; Volumes A-F. Final Report to the South Florida Water Management District, West Palm Beach, FL. hUp:/ /www.sfwmd.gov/org/exo/ftmvers/report-text/index.html Sample Secondary site basin Nitrogen Phosphorus TSS ERO Estero Ri ver 5.5094 1.2325 46.4 770 ERl Estero River 9.5685 1.9658 119.2340 ER2 Estero River 9.5685 1.9658 119.2340 ER3 Estero River 9.5685 1.9658 119.2340 HCl Hendry Creek 11.5284 2.3836 222.6800 HC2 Hendry Creek 8.8395 2.3333 136.4537 IRl Imperial River 9.4661 1.5906 131.9180 IR2 Imperial River 9.8083 1.6435 160.7623 IR3 Imperial River 10.0056 1.6739 177.3310 MCl Mullock Creek 5.2004 1.0490 64.7426 SCl Spring Creek 9.2296 1.6832 138.1570 SC2 Spring Creek 11.3219 2.6564 215.5180 SMl Six-Mile Cypress Slough 7.7393 1.4205 78.6170 SM2 Six-Mile Cypress Slough 8.1950 1. 7648 93.7500 SM3 Six-Mile Cypress Slough 4.5836 0.9822 61.7240 TM3 Ten-Mile Canal 13.0457 2.6801 248.3160 TM2 Ten-Mile Canal 10.2542 1. 7051 192.8600 TM3 Ten-Mile Canal 9.3330 2.1638 147.3530 Pelican Bay* Pelican Bay* 4.1 .043 59 Seagate* Seagate* 6.5 .093 179 * Yields normalized for subbasin size. total nitrogen load ([lbs/yr]/acre), total phosphorus load ([lbs/yr]/acre), and total suspended solids (TSS; [lbs/yr]/acre). Source: PBSJ Clam Bay Seagrass Assessment 2007. CAC Meeting- 10/13/11 Re: Clam Bay Water Quality NNC Submitted by Linda Roth North Naples , iJ-~ Staff has asked CAC to review and approve two reports. One titled Collier County: Numeric Nutrient Criteria Clam Bay- Development of Site Specific Alternative Water Quality Criteria by Atkins, and the other titled Dissolved Oxyaen Site Specific Alternative Criteria Development by Cardno Entrix. The FDEP technical reviewer was highly critical of the Atkins' report as evidenced in the 4-page critique titled Standard and Assessment Section Comments on Collier County: Numeric Nutrient Criteria Clam Bay- Development of Site Specific Alternative Water Quality Criteria. On Page 1: it states ". . . I cannot recommend that DEP support the current proposal or adopt it as a water quality standard because the proposed nutrients limits are overlv strinaent and perhaps unrealistic for Clam Bay. The document makes a convincing argument that Clam Bav is a healthv system. . . . The problem with the proposal is that it could lead to the conclusion that Clam Bay requires nutrient reductions both in terms of within-bay concentrations as well as within upstream waters (i.e., exceeding DPVs). The problem originates from the fact that the conductivity to TP or TN relationships differ between Clam Bay and Estero Bay Wetlands. [EBW]. " On Page 2: it states ". . . There are elements of the approach that DEP may want to consider, with some modification, for reference or existina condition based nutrient thresholds." Existing condition based nutrient thresholds means using the existing Clam Bay data to set thresholds. This is an element of the "maintain existing condition" or "hold the line" approach. However on (page 3): it states " . . . This assessment approach (Atkins' approach) is highly prone to trigger unnecessary assessments given the differences in the conductivity to nutrient relationships between EBWand Clam Bay. . . . Ultimately, application of the EBW derived limits to Clam Bay would require response evaluations more frequently than is truly necessary. " Not only nutrient standards, but criteria for Downstream Protective Values (DPVs) are an issue. On (page 3): it states ". . . inspection of the data and regression analysis suggest that the EBW DPVs would be overlv strinGent for Clam Bay. . . . The proposed DPVs would most likely necessitate substantial upstream nutrient reductions. " In summary, FDEP deemed the criteria proposed by Atkins in its draft report to be inappropriate for Clam Bay--overly stringent, unrealistic and likely to require unnecessary evaluation and implementation of remedies for a system that is essentially healthy and unimpaired. Yet this is the report being presented to the CAC for approval. Rather than approving Atkins' draft report as it stands, the CAC should be considering the revised recommendations presented in Atkins Technical Note of Auaust 31,2011. This revision incorporates most of FDEP's technical recommendations (although it does not revise DPVs as suggested by FDEP). The revised criteria would still tighten water quality standards for Clam Bay, as acknowledged by Atkins in the second sentence of the Technical Note, "The proposed NNC are lower (more stringent) than the Florida Department of Environmental Protection (FDEP) and Environmental Protection Agency (EPA) estuarine screening criteria. " This is substantiated by the attached comparison of state and federal water quality standards to the proposed criteria for Clam Bay. Presently, it would be easier for Clam Bay to meet the current FDEP and EPA criteria than Atkins' proposed criteria. It appears Clam Bay water quality has already met FDEP criteria. This begs the question, Why undertake the cost and effort to develop site- specific alternative criteria for Clam Bay that are more stringent than the current FDEP and EPA criteria? Why not simply abide by the existing standards? In proposing "more protective" standards, Atkins has relied on comparisons to a reference area that is not strictly analogous to Clam Bay. Estero Bay Wetlands (EBW) is open to the Gulf whereas Clam Bay is not. Are these "more protective" standards necessarily "more appropriate" for Clam Bay? The FDEP technical reviewer suggests the alternative of using existing conditions in Clam Bay itself as an appropriate basis for establishing criteria: On page 3: it states ''An alternative approach would be to develop existinG condition nutrient thresholds using the conductivity to TP and TN relationships from Clam Bay. The document already argues that Clam Bav is not impaired at existinG nutrient levels. " The CAC should not approve the Atkins' Clam Bay Water Quality Numeric Nutrient Criteria Report because the recommendations of FDEP's technical # review staff have not been included. It would be a mistake for the CAC to approve the July draft report without these substantive revisions. Also, the Cardno-Entrix research on dissolved oxygen (DO) levels in Clam bay is ongoing, with at least one more data collection period scheduled for the last quarter of the year. The DO results need to be combined with Atkins' work into a comprehensive final report and recommendations, since the criteria are inter- related. Rather than rush to approve a report that FDEP rejected in key particulars, please direct that staff and consultants take the time to develop site-specific standards for Clam Bay that are truly appropriate for this unique water body and in accord with the recommendations of state technical reviewers. Thank you for your consideration. . . COMPARISON OF CURRENT FDEP AND EPA WATER QUALITY CRITERIA TO ATKINS' PROPOSED WATER QUALITY CRITERIA FOR CLAM BAY Current FDEP & EPA standard for total nitrogen (TN): 1.0ma/L. Atkins' proposed standard for Clam Bay: 0.81 mall Current FDEP & EPA standard for total phosphorus (TP): 0.19ma/L. Atkins' proposed standard for Clam Bay: 0.057ma/l (3.5 times more strinaent than FDEP & EPA) The FDEP & EPA minimum number of samples not meeting applicable water quality criteria needed to put a waterbody on the "Verified Impaired List" is 7 out of 39 samples. Atkins proposes 6 out of 32 -39 samples for the "Planning List", and 7 out of 33 -40 for the "Verified Impaired List". The current FDEP & EPA standard for Dissolved Oxygen (DO) must be met no less than 900/0 of the time, i.e. maximum 10% exceedance. Atkins proposed standard for DO must be met no less than 950/0 of the time, i.e. maximum 50/0 exceedance. Recent Clam Bay DO data indicated that the Criterion Minimum Concentration (CMC) was never actually exceeded for the entire 24 hour period at any sample station. (Cardno-Entrix Draft Report) Recent Clam Bay data (2009 - 2011) showed that Clam Bay's chlorophyll-a values (a proxy for nutrient impairment) exceeded the current FDEP & EPA standards for estuaries only once in the 3rd Quarter (summer) of 2010. However, Clam Bay's 9.0 ug/l annual average for chlorophyll-a did not exceed the FDEP & EPA annual average standard of 11 ug/L. It is a natural condition that chlorophyll- a is higher in the warmer months. The FDEP reviewer recommends using the 11 ua/l threshold as a standard for Clam Bay. ID-l')-/I CC:l0 \L~~ ~'f 1\<\1-1 I, 1.\ I Li....\__ I I d' \, " ~ ~.-, J~ , C L. <.i / . J c, VV - ~ L. \,) n ..)tv .JC/( V"l 3' ~ illL .3 ---- -- --- - ~.~. ---- - I o I 34 -- , 119 I I I 51 68 85 Days at Large -820 00' -810 30' I 102 I 17 -83. 00' -820 30' -810 00' -800 30' I ~r' Data and map may not be us ,J{yra N!ote Marine Laboratory 4 (1 50 km , . ,--~ 0)\ J ~ /Q . / / I / I L ,>. ~ /,fi./u ~ - ~~..',>...:'...'....'..'."............'./;;:~.? Distance Traveled: 955 km I I -10000 -7500 I -5000 GEBCO Bathymetry Straight-line Distance: 6 km 1m I I -2500 0 27" 00' 260 30' 260 00' 250 30' 250 00' 240 30'