Tuesday, September 20, 2016 ICF International, 630 K Street, Sacramento, CA. Meeting Summary

Transcription

1 Tuesday, ICF International, 630 K Street, Sacramento, CA Meeting Summary Upcoming Meetings LAR BPWG 8 th Meeting: Tuesday, November 15, 2016 LAR BPWG 9 th Meeting: Tuesday, January 17, 2017 Meeting Summary I. Welcome, Introductions, and Agenda Review (Gregg Ellis, ICF) Gregg Ellis brought the Lower American River (LAR) Bank Protection Working Group (BPWG) meeting to order and noted that the group was convened a year ago. A majority of this time has been spent on understanding the broader erosion processes and looking at the analytical tools and methods available for analysis. The group has made a lot of progress on that front, and is ready to transition into more site specific investigations. Gregg then initiated a round of introductions (see Attachment A for a list of attendees) and provided an overview of the agenda. He solicited ideas for future agenda items, but there were no suggestions. II. Initial Feedback on July 19 Meeting Summary Gregg asked for feedback on the notes from the most recent meeting (July 19, 2016). Christian Carleton said he appreciates the increased level of detail in the recent sets of notes. III. Updates to the Lower American River Geomorphic Assessment (Ed Wallace, NHC) Introduction Gregg introduced Ed Wallace from Northwest Hydraulic Consultants (NHC) and explained that at the last meeting of the BPWG, NHC presented the results of their LAR Geomorphic Assessment and had a good discussion about the Assessment with the group. Based on that discussion and comments received from Chuck Watson on the document, NHC has made some changes to the draft document, which Ed will describe during the presentation. A revised draft will be posted to the BPWG website soon for further review and comment ( Ed noted that his goals for the presentation are to summarize the updates made to the LAR Geomorphic Assessment since the original draft was released in June 2016 and to review the findings of the Assessment. Ed began the presentation with a review of the Assessment s objectives and approach. The objectives of the Assessment are to (1) provide a physical process context to assist in the interpretation of modeling results and observations and (2) understand the past processes that shaped the LAR in order to help predict future behavior of the river. The approach 1

2 taken by NHC in the Assessment was to first assess several independent factors important in influencing river behavior, including floodplain and valley geography, hydrology, sediment supply, downstream and upstream controls, and human influences. NHC then developed a qualitative understanding of the behavior of different reaches of the LAR. Revisions to the Geomorphic Assessment Ed moved on to a description of revisions made to the Assessment based on comments received. In all chapters of the Assessment, NHC has added citations and more detail, including additional discussion on river processes and influences on river behavior. The biggest changes occurred in Chapters 6 and 7; the original Assessment had broken the LAR down into 5 reaches, but NHC has gone back and subdivided those reaches into smaller units. Descriptions of each sub unit have been added to the Assessment. Finally, NHC has added a new appendix (Appendix D), which is an analysis of historic banklines and how they have changed over time, particularly during the period. He provided an example of bankline change from the new Appendix D. This example focused on River Mile (RM) 10, and aerials of the river from 1953, 1957, 1964, and 1972 show substantial channel widening over those years caused by gravel mining. A review of the historical sources shows that there has not been a major shift in planform of the LAR during the historical record except for the gravel mining influences of the 1950s and 1960s. It also shows that the LAR is slow to regenerate the depositional deposits that were original features of the LAR and that were mined in the midcentury. The initial draft of the Assessment broke down the LAR into 5 reaches. The revised draft divides each of those 5 reaches into sub reaches for a total of 15 sub reaches. Each reach has common bed/bank materials, patterns of deposition, human modifications, and channel characteristics. The sub reaches are divisions of those reaches based on channel morphology, sediment transport, and storage. Summary of Reach Characteristics Ed then provided a summary of the characteristics of the original 5 reaches and discussed how each reach was subdivided into sub reaches. Reach 5 Reach 5 is characterized by a steep bar complex with active shifting. The bed is comprised of an erosion resistant unit, the Fair Oaks Formation, that dates to the Pleistocene age and controls the bed elevation of the upper part of the river. This unit is overlain by gravel. The banks are also comprised of both the Fair Oaks formation and Upper Modesto Formation, which is a slightly younger formation with high erosion resistance. Reach 5 was subdivided into 4 sub reaches related to morphology and sediment transport. Question: Peter Buck asked for clarification regarding what is meant by a steep bar complex does that mean the reach is vertically steep? Answer: Ed said that yes, compared to the rest of the LAR, Reach 5 is steep longitudinally. 2

3 Reach 4 Reach 4 is a straight reach that has been widened by gravel mining. The bed consists of gravel over Fair Oaks Formation, and the banks are Fair Oaks Formation with thick Upper Modesto Formation cobbles and sandy silt. Reach 4 was subdivided into 4 sub reaches. Reach 3 The LAR begins to narrow in Reach 3 as the river approaches Sacramento State University. The Fair Oaks Formation (overlain by gravel) is still present in the bed at this reach, however it slopes more steeply than the river channel, so as we move downstream, we are losing the influence of that erosion resistant unit. The banks are composed of a thin layer of Upper Modesto formation cobbles overlain by sandy silt. Reach 3 has been subdivided into 3 sub reaches. Question: Ron Stork asked if the sandy silt in Reach 3 dates from the Holocene epoch. Answer: Ed said yes, it likely dates to the Holocene, though maybe the late Holocene or even more recent. Reach 2 Reach 2 is slightly more sinuous than the previous reaches, and represents the limit of where we see gravel deposits in the river. At this point, we have lost the influence of the erosion resistant Fair Oaks Formation. The bed consists of gravel. The banks consist of sandy, silty sediments with some cobble. Though there are cobbles in the banks, this reach has also lost the influence of the Modesto Formation. Reach 2 has been subdivided into 3 sub reaches. Reach 1 Reach 1 is generally a straight reach that is influenced by backwater from the Sacramento River when the stage in the Sacramento River is high. The bed is mostly sand, and the banks are sandy/silty deposits. Reach 1 was not subdivided into any sub reaches. Geomorphic Assessment Findings: Sub Reaches where Potential Adjustments May Occur Ed then summarized the findings of the Geomorphic Assessment, which details sub reaches where we might expect to see future channel adjustments. Adjustments does not necessarily mean the same thing as erosion; it could also mean lateral movement of the river, vertical movement, or a significant change in channel morphology. Sub reach 5.1: This reach has experienced ongoing bed lowering in the past, and NHC expects that to continue. Ed also expects increasing stability as the bed lowers. Question: Ron asked if the bed is expected to lower through the gravels or into the Fair Oaks formation. Answer: Ed said that even though the Fair Oaks Formation is present in this sub reach, it is not necessarily consistently present in all places. Question: Mary Maret asked if sub reach 5.1 represents the location referred to as the nick point. 3

4 Answer: Brian Wardman responded that Ken Rood has referred to RMs 12 and 13 (which roughly overlap with sub reaches 5.3 and 5.4) as the nick point. Sub reach 5.3: This reach has been historically active, with coarse sediment deposition/bar formation and channel shifting. However, in this part of the LAR, the levees and bike trails are generally set back a good distance from the river. Sub reach 4.1: This reach may experience further sediment deposition along the left bank and, potentially, some erosion on the right bank. The levee and bike trails are generally set back from the river in this location as well. Sub reach 3.3: This sub reach has the potential for channel widening on the right overbank, which may impact the bike path and the levee foundation. Higher flows might influence this increase in width. Part of the left bank in this location is revetted, so widening is likely to occur on the right bank. There is less distance from the levee and bike path to the river in this sub reach (which stretches from the Fairbairn Intake to H Street). Sub reach 2.1: Ed expects to see continued mid channel bar growth in this sub reach. The bar growth has been associated with right bank erosion, which may begin to affect the golf course. There is risk of levee impingement on the left bank, where there is a very narrow distance between the river channel and the levee. This sub reach stretches from H Street to Paradise Bend. Sub reach 2.2: In this sub reach, there is potential for the Paradise Bend chute cut off to become the main channel. If that occurs, the bed could lower upstream and result in increased upstream velocities. This could affect the stability of sites upstream in Reach 2 (around H Street). Conclusions and Discussion Ed concluded by recommending that if the group is concerned about areas of the river where changes are expected and where the levee is close to the river, attention should be focused on Reaches 2 and 3. He then opened the floor to questions. Question: Steve Chainey noted that there is a lot of sediment storage potential in the reaches upstream of Reach 2. Presumably, whatever sediment comes downstream settles out in the widened channels and gravel pits in Reach 4. He asked where the sediment is coming from that is building up in Sub reach 2.1 s mid channel bar. Answer: Ed responded that the source for all the material deposited within the LAR comes from within the LAR, since no coarse sediment passes through Folsom Dam. Brian Wardman observed that recent HEC 6 modeling shows that three is still a lot of gravel upstream of Reach 5, and some of that material does get pushed downstream. Question: Ron lauded NHC s effort, through the Geomorphic Assessment, to describe the circumstances and ongoing processes that influence the LAR. He believes it is very helpful for the project purposes and an important thing to characterize. He asked if there will be an attempt to characterize post project environments or longer term processes on the LAR (like 50 years out). Answer: Ed observed that to some extent, trying to determine what long term future processes may look like on the LAR is what the Geomorphic Assessment already does. It looks at longer term processes from the historical record as well as evidence from stratigraphic mapping to determine how the river behaved in the past and how it might behave in the future. The Geomorphic Assessment attempts to put it in the context of longer term processes, including sea level rise. 4

5 Ron observed that it is difficult to describe future conditions because we don t know what the bank protection projects will look like at this point. However, he noted that one of the things the BPWG needs to do is post authorization design. He thinks it would be helpful to have some context not just of the nature of the classical bank protection benefits, but also to have some sense of how the projects themselves interrupt or change river processes. How we think the river would behave now might change as a result of hardening one bank, and that may cause ripple effects elsewhere. Ed noted that the Geomorphic Assessment steps back in time to look at a bigger scale than what might be looked at if we were talking about a specific erosion site. He said that, in a way, we are never done trying to understand the river processes. As one moves forward into looking at specific sites or a specific set of sites, we will look further into river processes on a more local scale. This Geomorphic Assessment is providing the context to do that well. Question: Mary observed that the photos Ed showed from Appendix D only go back to the 1950s. She said she has a set of aerial photographs from the 1930s she could share. Answer: Ed responded that NHC did look at aerial photography from the 1930s, but he focused on the 50s and 60s in the appendix because it was an era of active gravel mining and the closure of Folsom Dam. Ron mused that it would be a nice service to provide high quality scanning of old maps of the river and to make those scans widely available. Observation: Joe O Connor observed that another change in the area since the 1950s is the amount of urbanization that has occurred, which causes more water runoff to the streams instead of soaking into the earth. Response: Ed agreed that increased urban runoff can make a local difference along the river, especially where there are outfalls. However, the American River is a huge watershed, and the peak flows are enormous compared to urban runoff. IV. Discussion of Process/Methods to Investigate Erosion Sites of Concern (Brian Wardman, NHC; group discussion) Ed introduced his colleague at NHC, Brian Wardman, who would be providing the next presentation. Brian s recent work consider sites identified as having current or potential erosion concerns by the different evaluation methods, where they fall in context to one another, and where they fall in the context of the Geomorphic Assessment. The goal is to find out if another layer of screening needs to be developed for site selection, or even if a new method for site identification needs to be developed. The ultimate goal is to determine if these potential sites should be categorized as real sites of concern or not. Approaches to Date Brian provided a review of the methods that have been used recently to identify erosion sites of concern and anticipate where erosion might be expected in the future. LAR Erosion Monitoring (MBK Engineers) Each year, MBK Engineers performs a visual inspection by boat to identify erosion sites on the LAR from RM 0 to 12. Brian Janowiak provided a summary of MBK s most recent survey during the January 19, 2016 BPWG meeting. This effort identifies sites that are actively eroding and sites that may impinge on the levee or parkway resources. Brian observed that the LAR erosion monitoring 5

6 provides a good idea of what is going on in the river right now, but does not really give one an idea of what could erode in the future under big flows. Question: Ron asked how the LAR erosion monitoring is funded. Answer: Pete Ghelfi responded that it is supported jointly by SAFCA and American River Flood Control District (ARFCD). DWR Erosion Screening Process (ESP) Methodology DWR has developed an erosion screening process (ESP) that was applied to the LAR by NHC earlier this year. Ken Rood provided a presentation of the results to the BPWG in May This particular methodology serves as a planning level tool to evaluate the potential for levee failure due to erosion in extreme events at individual sites. The methodology takes into account geometry, soil composition, ground cover, and local hydraulics. It doesn t look at local scour processes; rather, it evaluates the levee s competence to withstand erosional forces in general. When NHC applied the ESP methodology to the LAR, it identified several places along the levees and banks that may be susceptible to erosion. Geomorphic Assessment NHC s recent Geomorphic Assessment (described by Ed in the previous presentation) serves as a system based approach to understand processes and relationships through the LAR system from a wide point of view (miles at a time) and over many years. It considers the interaction of hydrology, geology, sediment supply, sediment transport, and downstream and upstream controls. It helps us to understand what long term developments we may expect to see in the river, like locations where the river may be likely to move for one reason or another. Sites of Concern Identified to Date Brian s most recent effort involved plotting the sites of concern identified by each of the three efforts on one map to see if there were any overlapping sites that might indicate locations with critical erosion risk. For discussion purposes, Brian divided the identified sites into three groups based on proximity: the upstream sites, which are the sites upstream of Watt Avenue; the mid stream sites, which are the sites located between Watt Avenue and Paradise Bend; and the downstream sites, which are the sites located downstream of Paradise Bend. Brian also prefaced the discussion, noting that additional information may change his/our current understanding. Upstream Sites Brian considers the upstream sites fairly stable. Although MBK has identified erosion sites in this area, the ESP study does not predict concerns in that area in that area during a 160,000 cubic feet per second (cfs) event. Brian found it interesting that the erosion sites identified by MBK do not overlap with the sites/reaches of concern identified by the ESP and the Geomorphic Assessment. This stretch of the river is already over widened, and the substrate is stable, so Brian attributes the erosion in this area to local effects (like human access and a tree with an exposed rootwad causing local scour). Based on the geomorphic findings, he doesn t expect large scale changes in this reach of the channel, and wouldn t expect the channel to explode in a big flow event. Brian then showed the velocities and water depths in this stretch at 160,000 cfs as modeled by the Corps in their RMA 2 model. Many of the meeting attendees were surprised to see that there are depths up to 50 feet in this portion of the river. 6

7 Question: Ron asked Mary if the LAR Parkway managers have the ability to construct steps or something else that might reduce the amount of human caused erosion. Answer: Mary responded that the Parkway Plan doesn t say they couldn t do something like that, but they would not be able to call them steps without needing to make them ADAcompliant. Question: Steve asked for Brian s opinion on the erosion site identified by MBK at RM 10.5L. He said that when he was performing field reconnaissance with the Corps, the Corps seemed concerned about the site because the material was very sandy. However, it seemed to Steve that the erosion was mostly caused by human activity, and that there was not any evidence that there was a dramatic potential for bank retreat in that location. Answer: Brian doesn t believe there are processes at work in that location that would cause large scale erosion. He noted that the river bed is not close to the levee in this location, and that there are some erosion resistant layers higher up in the river bed. Rivers are supposed to have scarps and erosion, and it s possible that the erosion would encounter resistant layers before it ever reached the levee. Unofficially, Brian doesn t see the site at RM 10.5 as a big concern at flows of 160,000 cfs but recognizes additional information is needed to be more conclusive. Brian noted that Steve s question feeds in to the next discussion the BPWG will need to have. The BPWG will need to decide what site specific information it will need in order to decide which sites are critical or not. There may be active erosion sites at certain locations, but they may be determined harmless or critical depending on their distance from the levee or other infrastructure, the substrate type, and other site specific factors. Pete noted that one of the reasons for convening the BPWG was to figure out if there are any sites on the LAR that could make use of repair by the Sacramento River Bank Protection Project (SRBPP). The BPWG should work quickly to utilize the SRBPP as appropriate. Brian then identified the necessary next steps for determining erosion risk on the upstream sites. He called for continued monitoring and observation to identify potential channel instabilities and better understand the mechanisms behind the current erosion sites. He also recommended an effort to map Parkway resources (e.g., habitat, recreation, or non flood infrastructure) that may require protection if erosion or scour is ongoing. Downstream Sites In the downstream section, the ESP calls out three stretches as having high erosion risk. MBK identified one active erosion site, which coincides with one of the ESP high risk stretches. In this location, the levee is right next to the river, there are high velocities, and there is the potential for continued erosion. Brian then showed the group graphics illustrating the velocities and depths in this location at 160,000 cfs, as modeled by the Corps using RMA 2. Question: Ron asked why the river is hugging river left in this location and not accessing the substantial terrace on river right. Answer: Ed explained that the terrace is approximately 30 feet higher than the main channel. Question: Ron asked if NHC considers the river to be depositional over the right berm at flows of 160,000 cfs. 7

8 Answer: Brian said that based on the modeled velocity, there could be settling out occurring on the right terrace. It would not be surprising to see deposition there. The banks in this location are steep and sandy, which means they are not great rearing habitat for fish, so Brian believes lowering the right bank in this location to alleviate constrictions at higher velocities could be an option. Brian showed photos of the ESP high erosion risk stretches, and of the active erosion site found by MBK at RM 2.8L. He noted that the erosion site is characterized by an over steepened slope with a concrete flood wall on top. There is some revetment downstream. Mary noted that there is technically no levee in this location, and Pete explained that this is because the land at this location is high ground. However, there are areas nearby where ground surface is lower and could be flooded. Question: Steve asked what would happen if the floodwall was taken out. Answer: Pete said that the Bell Marine property (landward of the site) could flood if the floodwall was taken out. Brian laid out his recommended next steps for the downstream sites. As with the upstream sites, he called for continued monitoring and observation, identification of the causes of active erosion, and mapping of important floodway resources and infrastructure. Mapping of infrastructure can inform the group as to what needs to be protected, and also could provide clues about what might increase local scour risk. He also recommended that a detailed revetment map and revetment evaluation be undertaken to determine if the revetment size is adequate to protect against a 160,000 cfs event, and if the revetment is adequate to provide erosion protection to areas of concern. Question: Ron asked if SAFCA has a master revetment map. Answer: Pete said that SAFCA does not have a master revetment map, but Tim Kerr noted that the Corps does have one. Brian said that NHC updated a revetment map in 2010, but it didn t contain a lot of detail regarding size or depth of revetment. Question: Ron mentioned that the Central Valley Flood Protection Board (CVFPB) has tasked staff with finding levee encroachments. Answer: Bob Clarke confirmed this, and said they are working on that effort right now. Pete said that SAFCA is looking at encroachments as well under ULDC and SAFCA s accreditation program. It is possible that some of the problematic encroachments may actually have been permitted several decades ago. An encroachment that seemed like a fine idea 100 years ago might not be acceptable today; the CVFPB would have to decide if they are willing to rescind encroachment permits. Mid Stream Sites There are numerous locations within the mid stream region that are identified as high risk by the ESP and as sub reaches of concern by the Geomorphic Assessment. Geomorphic Assessment subreach 2.2 (Paradise Bend) is an historically active reach, and there is a possibility that a chute across Paradise Bend may form. A chute in this location could lower water levels on the upstream subreach, increasing friction, slope, and sediment transport capacity and lowering bed levels upstream. The bike path is located close to the channel (right bank) in this location and is at risk due to current local erosion. 8

9 The Geomorphic Assessment anticipates that some channel widening may occur upstream of the Guy West Bridge. However, there is an outcropping of erosion resistant material just downstream of the Guy West Bridge, so channel widening wouldn t be expected to occur downstream of the bridge. Sub reach 2.1 (H Street to Paradise Bend) was also flagged by the Geomorphic Assessment because ongoing deposition in the mid channel is causing erosion of the right bank, where the Campus Commons Golf Course is located. The right bank in this location is made of very erodible material. The ESP identifies the left bank in this area as high risk because the levee bench is minimal and instream velocities are over 10 feet/second. Development of a chute at Paradise Bend could affect deposition and velocity in this location, or could impinge on the levee toe. Ron pointed out that initial City planning efforts had development set back much further from the river in this reach. However, after Folsom Dam was constructed, people weren t worried about natural flood events anymore, and Campus Commons was approved for construction, significantly narrowing the levee to levee width. This segment of the river is now a raceway reach, but it wouldn t have had to be if the floodway was not so narrow in this location because of urban development. Question: Mary asked whether something might be done about the island if deposition there is causing a problem. Answer: Pete responded that the option is not off the table, but Steve pointed out that some islands on the Sacramento River have been removed and/or moved, and they have a tendency to re form. There s a hydraulic reason behind their forming in the first place. Brian noted that these islands also often serve as habitat. Brian explained that the Geomorphic Assessment predicts movement of the channel in this location as the mid stream bars push the channel one way or the other. The Geomorphic Assessment predicts that the erosion will cut into the right bank (golf course), because that bank consists of erodible material, whereas the left bank is somewhat more erosion resistant. However, the ESP points us to the fact that the velocity is high in this area and the left bank levee is close to the channel. This is a location that deserves further scrutiny and study to determine if the left bank levee is in danger or not. Conversation ensued regarding the tough decisions that might lie ahead regarding this unstable reach and whether or not to protect the golf course, or to let it erode in order to take pressure off the left bank. Gary observed that the golf course is within the floodway (between the levees) and he believes it would not be proper public policy to further constrict an already narrow floodway just to protect a golf course. He also noted that SAFCA does not have an unlimited budget and should prioritize protecting public safety with public dollars. Pete pointed out that even if part of the golf course is allowed to erode, it will need to be halted before the erosion reaches the two sewer lines that run underneath it, nearer the levee. However, according to Steve, one half to two thirds of the right berm could be lost before erosion got close to the sewer lines. Discussion then turned to the potential effects of a chute forming downstream at Paradise Bend. Mary said that there is a proposal to construct a side channel through Paradise Bend for fish purposes, but Brian noted that the idea has not been studied enough to know if it is a desirable change or not. Peter noted that presently, velocities are substantially slowed around the sharp bend at Paradise Bend, and a cutoff chute could increase velocity through that stretch and cause erosion elsewhere. However, Ed observed that the right bank on the far outside bend of Paradise Bend is 9

10 eroding now, and is only about 30 feet from the bike path in places. A cutoff chute may relieve pressure on that eroding bank, shifting the pressure downstream to the end of the cutoff where there is more room, all while protecting the bike path. Question: Steve remembered that several decades ago, Cal Expo was considering constructing a golf course within the floodway in the Bushy Lake area, where they possibly constructed a berm or plug along the right bank. He asked what the hydraulic and sediment transport effects might be if the elevation of the high berm on the right side of the river downstream of Paradise Bend was brought down. Answer: Ed said that generally, if the right bank were lowered, it would take some pressure off the left bank downstream of Paradise Bend. However, this effect would be dependent on the flow. He noted that the topography on that berm does not look natural; it appears to have been modified. There are also a number of electrical towers to consider on that berm. Brian shifted focus to sub reach 3.3 (Fairbairn Intake to H Street), which was called out in the Geomorphic Assessment as a section of the river that is getting wider, with erodible soils in the overbank. MBK also identified a couple of active erosion sites in this sub reach. These are likely being caused by the fact that the channel has been artificially widened, and there is some deposition pushing flow into the banks. The ESP shows a potential for erosion on the left levee near H Street, but there is a lot of toe protection already in place there. The ESP also shows potential for erosion on the right levee near the Fairbairn Intake. Brian noted that the 1986 flood event caused significant erosion on the right overbank. Brian s recommendations for next steps related to the mid stream sites are to continue monitoring and observation of the area, evaluate the potential impacts of a cutoff chute at Paradise Bend by modeling chute hydraulics and upstream and downstream effects, develop a detailed revetment map and evaluation that identifies existing revetment and transitions, and perform surveys and research to identify resources and structures within the floodway. Brian then turned the discussion to the overall path forward. He noted that several sites and stretches of the river have been identified already. The group will now need to decide if we should focus on looking further into these already identified sites, or if we want to go out and look for more sites. Brian recommends developing a site assessment approach that is adaptable to other sites, evaluating sites using the approach, and then evaluating the results of that approach. Brian then provided two examples of what site specific analyses might entail. These involved updating survey data; mapping existing features, resources, and infrastructure; assessing habitat values, assessing bank material; defining local erosion and hydraulic processes; and determining what would be likely to occur if erosion continues in that location. Brian asked the group to tell him what sites would be of interest to further examine. The following ideas were submitted: The left and right banks from Paradise Bend to the Fairbairn Intake; assess whether the rock at the toe on the left bank is big enough, and assess the effects of the jacket around the sewer on the right bank (Steve). Golf course bendway cutoff (Steve). Campus Commons (Peter). Right bank downstream of Howe Avenue because of the steep bank in that location (Peter). 10

11 Bell Marine site (Peter). RM 10.2 because of the sandy material and small bench in that location. Steve also said it would be good to know where historical (buried) channel deposits are in relation to where they cross under existing levees. There have been some cataclysmic failures in other parts of the Central Valley Flood Protection Project where buried channel deposits are suspected as the cause. This would require supplementing bank/bed material mapping with historic imagery. Ed noted that NHC has surficial mapping from the 1930s that was likely informed by aerial photographs. Gregg proposed that the consultants take the input from this meeting and narrow the identified sites down to 2 4 sites of interest and take a thorough look at those sites as recommended by Brian. Gregg would welcome any follow up thoughts from the group after the meeting. Peter pointed out the importance of getting the Corps re engaged in the BPWG. Pete mentioned that a process for involving the Corps has been established with the help of Bob Clarke. Gregg informed the group that he had a conversation recently with Stephen Osgood, the project manager for the SRBPP, who said has a continuing interest in the BPWG and thinks he may have more time to reengage as the Corps fiscal year draws to a close. Jim Morgan said he doesn t have a clear understanding of what the criteria are for SRBPP funding. It would be helpful, in selecting sites to pursue, if the BPWG knew what those criteria are. Gregg and Bob said they would work together to get some general criteria together. V. Meeting Wrap Up and Next Steps Gregg thanked everyone for attending the BPWG and provided a reminder of the dates of upcoming meetings (below). Upcoming Meetings The next meetings of the BPWG are scheduled to occur: (3 rd Tuesday every other month) Tuesday, November 15, 2016 from 1 3:30 p.m. Tuesday, January 17, 2017 from 1 3:30 p.m. Action Items Gregg will work with KC to post today s presentations and the revised Geomorphic Assessment on the SAFCA BPWG website ( He noted that Ed gave a presentation to the LAR Task Force the week before; KC will post that PowerPoint presentation to the BPWG website as well. The entire BPWG will review the modifications made to the Geomorphic Assessment (available at the BPWG link above) and provide comments to Ed Wallace at NHC. The consultant team will narrow down the identified sites of concern to 2 4, and will perform site specific analyses as recommended by Brian. Gregg and Bob will put together a summary of what is known about criteria for SRBPP funding. 11

12 Attachment A Meeting Attendees Name Annalisa Batanides Peter Buck Christian Carleton Steve Chainey Bob Clarke Gregg Ellis Gary Estes Pete Ghelfi Jennifer Hobbs Vance Howard Daniel Huang Tim Kerr Mary Maret Sara Martin Tancy Moore Jim Morgan Joe O'Connor Andrey Shvidchenko KC Sorgen Dale Steele Ron Stork Ed Wallace Brian Wardman Organization NOAA SAFCA CSUS GEI DWR ICF CEPSYM SAFCA USFWS GEI Delta Stewardship Council ARFCD Sacramento County Parks ICF NOAA SARA/Butterfield Neighborhood Association Butterfield Neighborhood Association NHC SAFCA Friends of Sutter s Landing Park Friends of the River NHC NHC 12