Good evening, everyone. I'm Daniel Amstitz. I'm the senior transportation planner for the town of Arlington, and this is the second meeting of the Mystic River Path connection to the Minoan Bikeway feasibility study. Here I've got Amber Christopherson from the Mystic River Watershed Association and also a couple of folks from Tool Design Group, and they'll introduce themselves in a minute because we go on to the next slide. So I know we've been doing this for a little while, but when you enter, everyone's muted. By default, please keep yourself muted if you're not speaking so we can avoid any background noise that comes in. You're free to turn on your camera if you would like, or keep it off if you are speaking. During the meeting, your video might be picked up, but we're recording it so that other people can watch this later and we'll put it onto the town's website afterwards. The chat is enabled for basically asking questions of the hosts, which we will get to further on about 20 or 30 minutes into the meeting. We'll have lots of time for questions and also comments on what we'll be seeing today. Again, if you need any information about raising your hand, it's lower part of the screen if you're calling in by phone. Star nine controls mute and unmute and star six is to raise your hand. And I think at this point, Amber, if you want to introduce yourself very briefly and then send it over to Stephanie. Sounds great. Thank you, everyone. My name is Amber Christopherson. I'm the Greenways Director at the Mr. Gribber Watershed Association. We're really thankful that you are giving up part of your evening tonight to join us and share your input. This is a really important project for us because it is connecting people of all ages and all abilities to some amazing natural resources in the area of the Mystic River, Mystic Lakes, the Aleway for Greenway, and Minuteman Bikeway. So we see a lot of potential here. Glad to be starting the process. Okay, get over to Stephanie, who's our consultant. All right. Thank you. I'm Stephanie Weyer, landscape architect with tool design and the project manager for this project. I am here tonight with Sneha Adekari from tool and Lucy Gibson as well. They're both engineers. Have quite a lot of information to present tonight. So I'm going to essentially kind of recap where we've been, what we heard from you in the last meeting and survey, and then give a high level overview of our various concepts, both kind of what's happening in the cross section in the corridor and intersection concepts for all of the different intersections in this project. At 8 p.m., we're going to try to start our question and answer session. We are really going to focus the first 10, 15 minutes on taking questions only, just because, you know, my presentation is staying high level. We want to make sure everyone's able, while they're able to stay on the meeting, really get some clarification for anything we couldn't cover in the presentation. 8 p.m., we'll start an open comment and additional question period and anyone who asked questions earlier on will be able to raise hands again. So with that, just want to give some brief reminders on what the project's about. This is a feasibility study. So it's a high level planning look at establishing an alignment facility types that fit in the alignment for a multi-use path from the Ale White Brook Greenway to the Minuteman Bikeway. So really trying to create, you know, this key connection between what are already two established paths, and again, focusing on intersections and creating safety improvements throughout this corridor at those major intersections and neighborhood connections. I won't read through this whole slide, but these are our goals. We presented these in the last meeting. Generally, you just want to reiterate some major points, which is that, you know, we're really trying to create an accessible route for all users, all abilities. Create that route, recognizing this as part of the walking and biking network between communities, between Arlington, Medford, Somerville, and to your neighborhood streets and local park spaces. Safety and comfort are, of course, a priority. But we also really want to recognize this is a place for people to be, and as they move along Lower Mystic Lake, Mystic River, we really want people to have a great experience and really be drawn to these resources. Just a little tidbit on where we are in the progress of this project, you know, we're kind of a little over halfway through here at the end of March. We have delivered an existing conditions assessment memo to the town. They'll be posting that online shortly right now. You know, we're having this meeting to go over our draft alternatives intersection place making concepts with you. We'll take the feedback in the meeting tonight and incorporate that over the next two months into refining more of our concepts into a whole preferred alternative. Development maintenance recommendations. We have some meetings with stakeholders coming up. We've already just had a focus group meeting recently and a stakeholder group meeting earlier this month. And then we're going to be wrapping that all into a feasibility study report. That's the final deliverable. It'll include cost estimates or detailed information on how to implement this project and carry it to the next stage. So with that, I want to briefly touch on what we heard in the last public meeting and survey. This is covered in detail in that existing conditions memo. So all of that information, the full survey results will be made available. This has to be a short presentation, so I'm just going to stay really brief. You know, public meeting, we had about 110 people. The survey, we had a 520 completed responses. And of those, over half were from Arlington. We did get a good proportion, 18% from Medford. And then other listed here, they primarily included Cambridge, Somerville, and Winchester. But there were several people from a number of different communities who responded. So it really shows how much of a regional value this trail can provide. I'm just going to skip a lot of the questions that were part of the survey, but just some key points are we asked people what are their major priorities. There were a number of different things you could have responded to here or write in your own answer. But really the most important and most frequently rated as most important were safe crossings, slow vehicle speeds, and then those connections between Arlington and Medford, particularly over bridges. Key safety concerns, far and away, we heard about the road or use and the lack of safe crossings there. All intersections were mentioned multiple times. A number of people mentioned along Summer Street, along the parkway as it heads down to the lake and along the lake. That space being constrained as it is, you know, is really uncomfortable to use. So a number of people commented on the lack of a usable shoulder for biking there. And then many people commented on poor sidewalk and roadway pavement conditions. A few key takeaways. Again, reiterating the need for connectivity with Medford, surrounding paths and the park spaces that are off to the side and on the other side in Medford. In a number of you really prioritized recognizing users of all ages and abilities, including different types of cyclists in the design. There's only so much we can do at a high level project like this, but our recommendations will be made to kind of carry forward into next stages and expand on those themes for different types of cyclists. But hopefully, some of what we've been thinking about will come through tonight and recognizing all users. A lot of you called for separation between cyclists and pedestrians. There are both a lot of pedestrians who really wanted their own space and some commuting cyclists who really wanted to maintain a faster space to move. So we thought about that. And then finally, what you won't see tonight is a connection through Buzzle Field. We heard from several people in both the breakout groups we had in the last meeting and in the public survey that Buzzle Field wasn't a great connection just due to all of the uses there due to game days. We also recognized in our own assessment that really Buzzle Field is going to need a master plan to kind of reconfigure that space to make a path work. So our concept deals with getting people along Summer Street and through the Mill Street intersection down to the Minuteman Bikeway. So those were just some key takeaways. Again, a lot of detail and many of you provided some really excellent ideas and kind of minute things to think about that are really important. So we did go through comments in detail and have really tried to pull those into the design even if I don't describe it tonight. So we want to go through an overview of our concepts kind of starting from a cross-section basis. So you're looking at the whole corridor from this is the Summer Street and Mill Street intersection on the left and the West and the Minuteman Bikeway all the way down along the Mystic River to L. Whitebrook Greenway on the right. Throughout the corridor we proposed one primary shared use path. That's the bright green line and greenish yellow. Where we have space we've proposed some accessory paths and one of those is a bike lane. We're currently proposing it as a two-way bike lane. This would start south of the Rotaries. Like I mentioned earlier the constrained space on Summer Street and along to the lake really doesn't allow for good incorporation of bike lanes. But we can do it south of the Rotaries and I will give more detail on these. We also proposed some separate areas you can see with the orange lines for pedestrian only path. So places to split off of the primary shared use path also down here at the Confluence with L. Whitebrook. And finally I'm not going to spend much time talking about them tonight but you know we heard from people within the meeting and the survey about meeting to either strengthen existing connections and making them safer making them more visible or handling various erosion issues between neighborhoods here and creating some new neighborhood connections. So we are thinking about those and I will present one concept that we're thinking about. So I talked about a primary path I talked about pedestrian only paths and two-way bike lane. All three of those can work in those three limited areas. Otherwise the primary shared use path is what we're saying is it's working throughout. The primary shared use path these these two cross sections you see here are part of the same design. They are not two different proposals. We're showing a wide cross section basically where the space is the widest how this would look and then constrained cross sections. Essentially we're looking you know wide along the river constrained along lower mystic lake at the bottom. And this primary shared use path we're proposing to be asphalt throughout from start to finish and with some changes in with again we we want to recognize that the need to make this path accessible for everyone. We also want to slow speeds. So along the river where we have space to kind of split out our paths. One thing we've done is propose a 10-foot wide shared use path something that's actually a little narrower so that we can get some soft stone dust shoulders on either side where we can create the space for the stone dust pedestrian paths proposing that in as well and those are generally proposed to be closer to the river. In the roadway we're proposing a two-way bike lane we've asked. We have a second public survey that we'll talk about but we also want to hear from you tonight about your preference between two-way bike lane which we're proposing on the river side of the parkway or just one-way bike lanes on either side of the road. We propose two-way bike lanes just for having shared space so people can ride fast but also ride together as a group and because there is a hill along mystic valley parkway just south of the rotaries that's give people a little bit more climbing space we avoid some of the conflict with dryways and intersections. We're looking to hear more about that with the the shared use path and we propose to keep it a little narrower from here to be able to accommodate shoulders. Asphalt is going to help us a bit with some of the maintenance issues that exist now with the stone dust and earth paths that are there today. Those wash out there's a lot of problems in winter. As we go more toward the constrained area that is already a narrow asphalt path and we're basically proposing to widen it in all cases moving the curb just out into the roadway away from the river and the path could really be between 12 and 14 foot wide. Again there's not enough space for bike lanes in this section but just trying to get as wide of a path as we can and as wide as a buffer as we can and this buffer can also arrange between six feet and a minimum 14 feet as a maximum. I will just say there is some finalization to be done in our conversations with the state with other stakeholders. So the widths that I'm talking about now may still change but generally this is our proposal and what we're taking into our conversations with the stakeholders and what they've already seen. Those are the cross sections that are part of the same concept. For summer street this works a little bit differently. This is a unique space and we propose 2 different concepts that we would like to hear from you on. These are also asked about in the survey. Summer Street you know right now is wide road that fills on both the north and south sides during game days with parking. We're showing 2 different cross sections one that takes advantage of the kind of space you can get if you were to remove parking along buzzlefield and on both sides of the road. So we're talking during game days. Just 2 travel lanes throughout they would be the typical with the travel lanes are often aiming for create as wide of a path as we can and we're able to get a little bit wider of a buffer to create a bit more opportunity for some landscape space and maybe are able to give it a little bit more of a park feel. The other alternative that we're showing down below is if we're keeping the parking on the south side or on the park side field side. This is a constrained cross section but it is a functional one. These are cross sections that exist elsewhere including on Mass Ave in Boston. But you know this is as narrow as parking would go. Your path gets a little bit narrower. Sorry for all the pop up boxes and try to move my mouse less. But your buffer is essentially it's essentially just a hardscape buffer is just going to be functional to try to prevent you know give enough space to keep people from getting door when they're in the path for both of these cross sections. We are proposing and we discussed with our stakeholders moving the existing utility polls. You know right now if you walk along summer street the sidewalk is very narrow with those utility polls. And so it's everybody just kind of agreed that really we're going to get the best design not obstructs path. Not create any accessibility issues by just going ahead and investing in moving those utility polls. So that is the long-term vision for summer street with 2 different concepts we want to hear about parking or no. So this brings us to intersections. I'm going to go through each one. There are a lot of different things that went into these intersection designs. But I'm just going to hit on some major points and clarify things if you have questions starting at mill street and summer street. The image north is is to the right of this image. The summer streets coming in from the West here. The big the big points here that we've removed all the medians around this intersection and the right turn lanes to really tighten up the intersection. Shorten the various crossings around the intersection and really slow vehicles down on these terms. With summer street on the West side we've proposed as part of the long-term vision carrying bike lanes through so really creating work at a gateway with this intersection into the path connection. And then finally you know we proposed with the tightening of the intersection more of a protected intersection for cyclists. So there would be raised curb on each of these corners. So by taking out of this meeting as we really get a generous amount of space and are able to create a comfortable path and a comfortable intersection to transition around to get down to the minute man likely. Moving east along summer street. This is the one neighborhood connection concept I'm going to show tonight. Generally these ideas would kind of carry along to the other neighborhood connections across the parkway. But for summer street and Victoria road Victoria road has a crossing existing today on the east side. We are proposing to move that crossing to the West side. We understand this is the sauce of something that's been discussed by the town Transportation Advisory Committee. That's really you know doing some good things by lining up the crossing with the entry to buzzle field. It also places the crossing more on the crest of this curve and kind of increases the visibility for drivers to see people who are in that crossing. And generally we've proposed advanced warning signage and are thinking probably a rectangular rapid flashing beacon. So this bright yellow signs with blinking lights are fees. Those likely work well here to any other concepts generally I'm not going to spend time getting down to the details on signage. But signage and pavement markings can really help increase visibility throughout any of these concepts. Going further east to the summer street mystic street mystic valley parkway intersection. You might see here the key point is incorporating this diagonal crossing which is really meeting the desire line for the path as it comes in on the south side of summer street and then transitions over here to the north side of the mystic valley parkway and then it stays on the north side of the parkway. To do this. We have removed the right channelized turn lane or the slip lane on summer street and expanded out this curve. You know the design within the curve is to be determined. But really this allows us to accommodate all kinds of crossing space. We've worked bike lanes into the center section as well on mystic street. And with this diagonal crossing right now this fits the way we have modeled it within the total existing signal cycle link for the center section is crossing works but essentially what we're doing is where where you have a really short. There's a dedicated phase or exclusive phase for pedestrians across now. It's very short today. We're proposing to lengthen that out. Essentially cars will wait longer. But the total signal cycle length would be the same. And the other big benefit to this crossing besides following this desire is really preventing some conflict with the gas station. This is a very hard space to work around. There's not a lot of sidewalk space to work with to create any kind of queuing if we had people go on 2 legs. So going down to Medford Street high street. The roaderies today we're trying to turn into modern roundabouts with crossing incorporated throughout pads on both sides. You can see that we've incorporated crossings on both sides of the river to really meet the desire lines with existing paths. This bridge is 60 feet today curb to curb with 8 foot sidewalks behind that. So that gives us so much space to work with you. We're not able to really build anything out on the bridge without reconstructing the bridge. So instead we've proposed to 2-way bike lanes on either side to kind of support whatever loop someone might be making. In general we have formalized these roaderies into roundabouts and really tightened up all of the geometry so that vehicles do have to move slowly through. We propose truck aprons for larger vehicles on route 60. So they will be able to get through and more of a straight movement that doesn't prevent their movement. Finally I'll just say that you can kind of see that the crossings are set back from the roaderies and you know one reason we do this is to make sure that any vehicle that's approaching they're not sitting on top of these crossings and ignoring who might be within the crossings as they're trying to nose in to the roundabout. Finally we're headed all the way down to River Street or the Harvard Avenue bridge. The big thing we've done here currently the informal pedestrian path is up by the bridge. It's more of a mid block crossing. It's about 90 feet off of the intersection. We have pulled that pedestrian path down and made it part of the whole primary shared use path and incorporated a wide crossing here that takes into it both the path and all of this existing sidewalk area and the movements people are making there. We've proposed you know as follows kind of plans set out by both Arlington and Medford bike lanes on either side of the intersection. You can see the two-way bike lane coming through east to west. And I think just kind of want to note that the gas station on the southeast corner we would be closing this driveway to accommodate this. So those are the really big points to cover in the intersections. And lastly I talked about really creating an experience. We've thought about some just kind of big ideas in terms of place making of course you already have benches out there today. Some people have mentioned wayfinding. We know that's a priority. But that's kind of something that will be part of recommendations. These are really just kind of big place types that we want to think about and get feedback on. One is way sides. You can see them starred here on our different connections to the Minuteman and Illinois Brook Greenway also in the middle south of the Rotaries. A wayside would essentially be kind of a small gathering space and orientation area that includes a map kiosk interpretive signage seating bike racks bike repair stations are something that people have suggested that can be incorporated. So they're good places for people to kind of stop along the trail. Scenic overlooks we're showing 4 locations one up kind of close to the culvert Melbrook under the lake. One at Hays Street and then one west of the Harvard Abridge. One at the confluence and Mystic River with L.Y. Brook. We're showing 4 locations. Wood 4 overlooks definitely be built. That's to be determined. But we're looking to get input on those locations. Generally when we talk about overlooks you just look at the picture on the bottom here we're talking about small wooden construction. So nothing to outlandish. And then nature opportunity areas. This is you can see these here. Actually I'll go to the next slide. We've proposed these north of the Rotaries on the curve where there's a big wide open space or you can maybe just see the crossing at Palmer Street here and essentially the space that's just a cross from that crossing or again near the L.Y. Brook Greenway connection. Those opportunity areas we're talking about for things like native planting, rain garden, butterfly gardens. Apparently some people have suggested orchard planting. Interested to get more ideas on what those could incorporate and the potential locations for those. But they're good opportunity for preserving and enhancing the habitat and ecosystem along the path. So with that that's all of the concepts in next steps or just what I mentioned before we're headed into more refined stage of design once we have your feedback tonight still at a high level. We'll be working toward various recommendations and cost estimates and really trying to package all of this together. We'll present a final report to you in June. Everything I presented is in a second and last public survey which I think Sneha will be adding the link in the chat. So if you could please pop into the survey and give us your opinions. That would be great. We are now going to go to somehow I will eventually prevent my screen from going yellow. I not figured this out yet. How to get it to stay. We're now going to go to the question and answer session. Really want to reiterate we want to stick with questions at this time. We absolutely will take comments. And anybody you ask a question now you're going to be able to raise your hand in the comment period later if you have general comments. We really just want to be able to clarify information now while everybody's still here. So with that I'm going to leave the slideshow up in case I need to go back to any slides. We will be if people want to ask questions in the chat they can. You're also welcome to raise your digital hand which again you do by going to the bottom of your screen. There we go. The reactions is not showing on my screen. So yeah that worked. As the presenter I don't see it. Hey Stephanie I've got some questions through the chat that came in while you were talking. I can briefly go over those if where that works to start that way. Yeah, let's turn that and then we'll go to I see John has his hand up. We'll go after you, Daniel. So yeah quickly I have answered everybody. Three or four people have asked some questions to start with but I'll just read them out and briefly maybe add a little bit. Jennifer asked about the parking on Summer Street. Will you propose what other options people have for parking or will that just be a necessary compromise? And so basically that is to be determined. I think the if you were to just sort of say remove parking from Summer Street people would end up parking into the neighborhoods. There are some side streets such as Victoria Road, Johnson Road that do sometimes get parked up. I actually used to live very close to there. Understanding that that may be a hardship for the neighborhood residents if that were to happen. It's the sort of thing that would still need to be determined through like another parking study or further as this project moves along. I think we're trying to get through here some feedback on that whether or not that's sort of worth going that route or whether you know still retaining parking on Summer Street is useful and certainly a conversation we need to have with the Parks and Recreation Commission and the Recreation Department here at the town. Let's see a couple of other questions. Let's see. A couple from Ellen about whether the sidewalks would be replaced. The answer is yes. Basically all these areas where there's existing sidewalks would be replaced through this project to build out the trail. I will just add that I believe the Public Works Department in Arlington is planning to do some sidewalk replacement on Summer Street and you know we'll need to work with them on seeing how we can coordinate some of this. I don't think they could do you know they couldn't sort of move curves and utilities at the same time but they may be making some sidewalk repairs in the near future. And then I think one other question oh another question about the trail surface I think Stephanie maybe you mentioned it was going to be asphalt. I think that's that's through throughout the entire project except for the stone dust pedestrian path. But that would be asphalt along the lake and also along Summer Street is that right? So this entire green line would be asphalt. Okay and then the last question from Sarah was about the two-way bike lanes will they have a physical barrier between them and the car lanes along Mr. Valley Parkway? So the answer is yes that's the idea and but that's still to be determined with the Department of Conservation and Recreation which would actually have to maintain that barrier. So that would need to be figured out during the design process as well. And so that's those are the ones that came in while you were presenting. I seem to have some just direct message questions as well. One is how do you anticipate the increased paved areas will impact water quality and erosion from stormwater runoff? We think that the paved path is going to help prevent some erosion. We do think this is going to need you know plenty of consideration and planning and conversations with the Conservation Commission going forward to mitigate some of you know if we are paving what do we need to do to mitigate the impacts of that flood perspective. I think from a water quality perspective I don't really foresee major impacts there but I won't pretend to speak to that. I think one opportunity that we have is in those nature opportunity areas and generally just as design would go forward more thought can be given to how the paths kind of interact with you know planting along the bank. Generally we're trying to peel those paths somewhat away from the banks and particularly in the constrained section if we can create a little bit more space at the top of the bank so that more planting could happen and that could help mitigate some pollutants. The last the last or there's two more direct messages to me if people could direct their chats to the general chat room be helpful as I'm actually not seeing a lot of other messages. I'm sorry I change this so that people can only chat to us but I think they're just going to maybe going to just one of us at a time. Okay yeah because I couldn't see yours Dan. Sorry about that so how about we go to John who's been waiting to speak maybe maybe go to the people that are waiting to speak live and then we can go back to the questions that are in the chats. Sure and again just want to take questions from people who are speaking as well. Go ahead John. Thanks Stephanie this is all really really inspiring and great and exciting and I'll reserve sort of comments and ideas for later. My question has to do with Mystic in front of the police station the Mystic summer intersection and the question really has to do with any sort of work that was maybe looked at in comparison with the intersection in the center of town where the where the bike path crosses Mass Ave and Route 60 pleasant I guess it is. So so just kind of looking at those two and and kind of discussing sort of like traffic patterns eastbound on summer going southbound on Mystic and kind of just why the decision to do the the diagonal as opposed to something like what exists in the center of town. So two big things on the diagonal were you know preventing conflict with this gas station just because there's not a great place to have say cyclists to queue out in the roadway with how this gas station is configured and there is an existing gas station entry here. You know so that was that was a big one. Another one is really just providing that direct line from corner to corner with that exclusive phase so they go hand in hand having that dedicated signal phase. Dan is there like a history to the consideration that the other intersection and it's a different using a configuration. It was a bit before my time. I think that project actually started design around 2010-2012 or so. So it took a number of years before I had the Mystic Mass Ave pleasant street. So I have more recently been looking at some of the old concepts for that project. I believe a direct diagonal crossing of Mass Ave from like one end of the bikeway to the corner with the Cambridge Savings Bank was considered or as one of the potential concepts. I would say if I had to guess I can only sort of speculate since I don't know as much about the history was probably that in order to provide that you do have to provide like an exclusive pedestrian phase or bike phase you could say and I think for Mass Ave Mystic pleasant it was probably too great of a delay for either people wanting to cross from the bikeway or drivers and people along the street trying to cross have that exclusive pedestrian signal. There'd be a lot of delay for everybody. So they made it sort of concurrent so that you can cross you know and when people are going east or westbound or the other way. That's again that's my speculation as to why that was sort of chosen that way. Yeah thank you. I mean I think that a lot of the concepts that were shown tonight I think you know really they open up a lot of questions and but they're in the right you know the right path. So I'll let other people ask. Thanks. Thanks John. We'll go to Beth next. Thank you and special thanks for having evaluated and giving consideration to the current use of Buzzlefield. Many of us appreciate that. My question is are you prioritizing and I hope you are prioritizing preservation of mature trees in the project particularly along the river and that green existing green space there on both sides of the road but really everywhere that they're just so essential to the community and community health. I'm concerned and curious about the areas that you showed along the Mystic River when you showed the cross cuts how you fit all the paths on what is essentially sloped area. I'm curious as to how you do that. If you can show that. You're talking. Yeah yeah yeah yeah so yeah this is like this is showing like the absolute widest cross section where there isn't as much grade separation right. Well the lower one is that the that's along the curve of the Mystic Lake on Summer Street is that or Mystic Valley Parkway is that what that is? Lower one. Yeah so this this would basically be right here. Okay we actually have about 10 different cross sections but can only show so many in this meeting. Go ahead. Thank you so along the lower Mystic Lake that curve right there for the nature perspective rather than overviews I'd suggest a boardwalk along at the water level if you can do it. You know you have obviously you have the bike and path at the top for bikers and walkers but if a boardwalk could be considered at the lake level that would be terrific. Then if you can go back to the cross section along the Mystic River the upper yeah I'm just wondering how you fit all that space. You have the road on the right the two-way bike lane and everything and then on the left there you show that level green space going to the level bike path on the left that two foot crushed stone path really like the crushed stone and then the bike path so I've walked this along the Mystic Valley Parkway along the river from Park Street up to that intersection by the gas station and it's not flat it's slanted. Oh yeah um yeah so some of those other cross sections that we're not showing in the hill south of the rotaries here in this case you can see there's no pedestrian path this is where the hill is located the pedestrian path is just the orange line so that's that's really you know the we're just kind of using this cross section to really talk about where we have that much space we can incorporate this separate path but yeah through through along this hill I mean it's a much more narrow area so you're only going to get the the shared use path. Okay so I'm sorry with asking all my questions I didn't hear are you prioritizing preservation of trees? We are that is that is a that's one of the goals I did not mention at the bottom here preserving tree canopy I can show you in the just from a basic level in our concepts you know we're even kind of thinking about path configuration around some of those existing trees in some of these concepts we'll just be making recommendations for avoiding those also dealing with some of the slopes that are off to the side so yes generally these these path configurations are looking to preserve existing trees. And I'm also just going to remind folks I'm trying to keep us moving if you could just ask clarifying questions right now rather than getting into more comments that would be useful I think but those are some really good ideas and appreciate your thoughts. This is Dan how about we go to David and then Thomas and then I have like 20 questions in my chat so and then so see if we can get through some of those. Can you guys see me? Yep. Hi go ahead. Thanks for the presentation this was really great actually I had not paid attention to this project but it's good that I stumbled across it it was fantastic work. My question was and that goes back to many years trying to get the lighting on Mystic Valley Parkway between the lake and you know street lighting repaired I submitted out a couple times because it's pitch black dark in that area between the gas station to gulf gas station up there and and there are light posts and you know all the way down there they're light posts they've been going out over the last couple years so I live pretty close to the low Mystic Lake over the last I would say 10 15 years and DCR in the town of Arlington have never been interested so I'm just wondering how does lighting or street lighting you know how have you looked at that it's a completely pitch black area down there. Well I can tell you in the in the cross sections you know it's a little hard to see I imagine but we have kept street lighting in that area as per whether the they would have to move outward with the buffer but generally propose to keep it as for lighting going out that you know that's outside the scope of this project. The other question I had is the connections to the neighborhood you know again very close to the lake you have it as red dotted lines not this one but the next one up towards exactly those two probably connecting to Davis Ave and Kimball they're already you know being used because nobody wants to go obviously through the tricky intersection right now next to the gas station so I'm wondering what the design looks like that you had in mind it's a pretty steep I would say 10 15 feet elevation gain between Mystic Valley Parkway so I bike there quite regularly and Davis and Mystic Bank what's the design that you had in mind for that. Well this one these connections are probably the least thought out since we've kind of focused more on getting people on the connections across the road but you know we have seen those those paths the road we know that debris from those paths go down into the path so I think we're trying to consider how can we prevent that as for particular proposals frankly we have to give it more thought but I think that's something that we can definitely flesh out and for the next stage we know those are a priority. Again I think they connect well to Route 3 again a lot of people bike up Route 3 and then around the upper Mystic Lake so that's quite a popular bike route so connecting pretty much the Mystic Valley Parkway and not having to go through the more tricky intersection I mean hopefully that intersection is not going to be as tricky going forward as it is right now but a lot of people I've seen trying to make that connection to Route 3 and then upper Mystic Lake pretty much route through those two connectors Kimball and Davis slash Mystic Bank. Thank you Thomas we'll go to you. Yeah hi I'm a cyclist also I live up Mystic Street a few blocks and my primary use of biking in this area is actually to get from my house down to the Minuteman path heading west so I'll typically come down Edge Hill roads at the name of it or Brookdale pick up Summer Street to the Mill Street intersection so with your path on the far side of Summer Street when approaching from the north is there easy access at those intersections to get up on to the path to continue over to Mill Street or would I simply be merging with automobile traffic to get to the Mill Street intersection. It's actually it's a great point in terms of Brookdale and Edge Hill road which you can't really see in this image how those would access. Right now we've kind of funneled the access through Victoria road but I think what would be possible is making cuts essentially that allow people to slope up on to the path at any of these roads. I think we need to give further consideration to whether we'd actually have an official crossing at these but yes any of these could be made accessible and unfortunately I don't have an example of it we've done it elsewhere by creating a slope that allows you to bike up onto the path from an intersection. And Stephanie I'll just add as I think I mentioned before I lived very close to here and would frequently see people going the Victoria road is one way going towards Mystic Street from Summer Street but all the time would see people going the wrong way on Victoria road to go because that was the best access easiest access to get through Bustle Field then they get to the Minuteman. Victoria road is very wide it's very sort of strange street it's you know it's probably like 25 or 30 feet wide going one way. So you know potentially I could see some way of making a better access point through the Victoria road crossing you know by allowing people to go the other way or a safe way of being able to go the other way in Victoria road because it is the most direct access but yeah Brookdale and Edge Hill are not certainly right now are not very easy to actually get to the bikeway from there rather than riding on the road. Yeah that would make sense to put a two-way bike lane on Victoria perhaps. Just another comment sometimes when I'm biking in Medford and I want to get to my house I do not take Mystic Valley Parkway what I do is go down Medford Street and cut through the cemetery to avoid traffic on Mystic Valley Parkway and to avoid a turn at the Mystic Valley Parkway and Mystic Street intersection. Thank you. I'm just going to let people know we are you know in the open comment and question period at this point I do want to go back let's say to Dan's chat Amber are you getting chats? Not really. I have a few questions and comments that came into mind but Dan let's take yours first since you give some older ones I have some older ones and then we'll go back to raised hands after the chat. Yeah since people asked some like 20 minutes ago so I want to see if we can get through those somewhat quickly. Kathleen asks is the gas station entrance on the corner proposed to remain at Mystic and summer? The answer is yes but I think it would be narrowed significantly is the idea. Is that right Stephanie? Yes right now it's 27 feet wide and it's one way in so we would propose to narrow that it would be very complicated we think we've not had a conversation with the gas station but the way their pumps are organized probably be quite complicated to actually close this driveway. Thank you. Let's see Patrick asks or says the stone test and paved configuration is interesting is there a cost savings associated in terms of constructions and construction and or maintenance? Do you know the answer to that? No honestly no. Well maintenance it's quite different between the two right? Yeah I mean maintenance we didn't expect the asphalt path to generally be cheaper. I would say stone dust is not like it's not a cheap material necessarily so it's not it's not going to be a massive cost savings but it would potentially be cheaper to install certainly not to maintain it would need a lot more regular maintenance than asphalt. Thank you. Okay Gina asks a couple of questions. One is about the stakeholders and the focus groups so we as part of this project we have a project team made up of representatives and staff from the Department of Conservation and Recreation which owns the Mystic River Reservation and the Missing Valley Parkway. Massachusetts Department of Transportation which owns the actually the bridges that go over the Mystic River and the Lawrence and Lillian Solomon Foundation which provided funding for this project as well the Metropolitan Area Planning Council and of course the town and the Mystic River Watershed Association. The focus group which took place last week included folks from our Transportation Advisory Committee in Arlington, the Bike Advisory Committee residents from Arlington who live you know East Arlington near the area and also residents of Medford. I think some folks represent like the Complete Streets Committee in Medford and the Walk Medford so those are a few of the folks and also from our Environmental Planner representing the Conservation Commission so that was a focus group from last week and then she also asked a question about the guardrail about why it's located on the lakeside and not between the path and cars. I don't know if I can fully explain that you know part of that that's I think that's a traffic engineering purpose for that so that cars do not fly off the road into the lake but as part of this we are actually looking at and talking to DCR about whether or not there should be a guardrail in between the path and the road. And they actually they have a whole kind of their own requirements and warrant process for determining whether that is necessary or not so they'll take into account the width of the road the distance from people on the path speed of the road so that that is an ongoing conversation figuring out those barriers and whether there should be one between the path and the roadway we'll just also say you know the buffer between the path and the roadway can be up to 14 feet wide since in some cases it just may not be necessary due to the width of the buffer six feet is kind of the minimum buffer width and might be a good idea in that case. Thank you. One thing I want to add to what Daniel said too just regarding the focus group is that it was the same content that's being presented tonight so it isn't anything that was like different. Yeah okay okay so moving on Sarah says what's the level of involvement from the cities of Medford and Somerville so actually the project team I forgot to mention the city of Medford and their transportation staff have been coming to those meetings and involved and is aware of all this and is very excited about it and then also the focus group I mentioned had several people from Medford West Medford or part of their city committees as part of that Somerville I think there may even one person related to Somerville but it doesn't quite it does certainly connect into the Mr. River path that goes into sort of Somerville Medford but the Medford connection I think is sort of has been the more important piece of this. Let's see so B Dan Fairchild says like Harvard Ev he's asking about the signal phasing for the two-way bike lane will be separate will there be separate phases for bikes just for pedestrians will it happen every cycle where a button or will a button have to be pressed I don't think we've gotten that detailed into how that would work but I don't know Stephanie if you could sort of generalize on the thought process at the Harvard Harvard Street River Street intersection overall signal operations we've not gotten that far you know there would definitely be a couple separate sets with this wide crossing of pedestrian push buttons right side of path and then down by the intersection but overall signal phasing for this one we've we've not thought out Lucy if you have thoughts on that we have Lucy a traffic engineer you know you're welcome to join in. I think the issue of whether they are activated by a push button or always put on recall in this case if they are concurrent with the movements is something that we could certainly consider but the bike crossing has real limits as well on whether or not you can have through movements on Mystic Valley turning across the bike lanes so we may need an exclusive phase for all of those having it wider doesn't affect that the signal timing so the width of the crosswalk doesn't really affect how much time we need to devote to the pedestrians. Thanks all right yeah we've looked at a lot more detail at Summer Street but not so much here because it seems much simpler. Alright so I'm moving along I'm getting quite a lot of them here so you see Jay Fills asked about the DCR property yes it is DCR property in terms of maintenance and whether or not they cut the grass that's sort of outside of the scope of this but they will need to maintain you know the path that is built and they they do. Gina asked another question about the poles the utility poles can be replaced or can be become very power lines I think the answer is potentially yes I don't I think I don't know what the cost savings or the cost addition would be for that I don't know Stephanie if you want to add but essentially the utility poles would need to be moved to make this a decent path and again avoid the accessibility issues that Stephanie mentioned. I think it's it's fair to add that our you know our project team proposed that as well and you know so that that is an option on the table which needs further consideration. Great um Dan do you mind if I go back to some of my questions that have been sitting for a while? Sure um so there's a question I've got 20 more about so. Okay everybody keep directing your questions Dan keep some um I just have a I have a suggestion I don't know Daniel if it's possible for you to write the answers to some of them while Stephanie answers. Is there some simple one? Sure yeah I don't know if that's possible sorry. I can write it to everyone so yeah I can write it to everyone yep go ahead. I've got how will bikers from perpendicular streets along Mystic Valley Parkway access the off-road path um so jumping around. It can't be done everywhere there's a hill here we cannot get around that um you know here is a flat area so essentially kind of some of the basic crossing ideas that we proposed here that we can think them out a little bit more for for bike you know bike exclusive crossing in in relation to the crosswalk you know that would kind of work the same in that we want five visibility crosswalk markings signage potentially RFBs the flashing beacons to increase visibility those types of things for those crossings. Um we took a question on this earlier these work differently um and would need a different kind of thought um as for the issue of parking during games on the park on summer street could an accommodation perhaps be worked out with the Fresh Pun seafood market I love that um but uh I don't know honestly Dan any thoughts on that I'm very sorry I was looking looking at all my chats um can you say that say that again uh there is a question about could an accommodation perhaps be worked out with the Fresh Pun seafood market per game day parking on summer street. That has crossed my mind actually as we were talking about it today because they do have a rather large parking lot area I think that is something we'd have to explore with them but probably not a guarantee so I think the conversation about the parking on summer street is uh something of a question we need to work out. I'm going to go ahead and make a couple comments that came through the chat a comment not a question I'm a senior who likes to walk along the river and the lake I love the many benches this is why I choose to walk or choose this walk I also appreciate the four parking spots at aleway parkway at the mystic valley parkway however the rotaries at high street and medford street are a nightmare to cross I'm not nimble enough to dash with my walker through the fast moving traffic to get from one walking path to another that's one comment and I will just mention you know we didn't show it in our plans but certainly we'll be keeping a recommendation to keep those benches that are dotted along the path I think we can skip that one would the path have lighting we got a number of comments on this in the original public survey public meeting that is to be determined I do think that where lighting exists today along the lake most likely would propose to keep it and along summer street but we've we've heard different ideas on this and I think really we have to have a conversation with DCR about whether there would actually be lighting within the park space versus on the road where it exists today I think it it is also along the road all along the parkway as far as I remember and some of that I will say gets to the balance of are we doing something to harm you know animals by having more lighting along the path while others really want you know comfortable lighting for evening rides winter time rides so to be determined it is an important topic that we'll address but more a couple more comments and then Dan I'll send it back to you hope you've included Arlington housing authority for the Cusick Terrace residents on summer street and the not in mean manner near Mr. Valley Parkway essential to take into consideration safety concerns for Cusack Terrace and concerns of its possibility for not not in mean manner it's from Beth thank you Beth I think you know further communication with them is something that will will happen going forward oh that's when it comes from Dan I will skip that for now lastly even though the goal station entrance on summer street mystic street is one way in often cars do use it to exit the gas station would be safer to close this entrance thank you good to know the dental I will send it back to you for the the questions and comments you're getting there actually so I went through them and there is sorry I'm getting some feedback here there was a number of different comments related to the safe travel project just sort of uh talking about um some of the issues with that I'll just just add in for people's information this is the mass have mystic street that there was concern that pedestrians wouldn't be able to cross though the you know across the entire intersection diagonally um Christopher mentioned Dean has said it was deemed unsafe because of beginner cyclists or children whatever hard time getting through again the entire intersection um and then and then also about the you know the need to ensure that I guess we didn't you didn't didn't increase air pollution because of idling cars and that was sort of a compromise that had to be made so thank you everyone for adding to that there are several other there are several other comments um and I can go through there but let me let me actually get to the questions um and I've answered a couple of them that I could but there is uh maybe Stephanie if you can speak to this about having an on-street bike lane and a paved path between the rotaries down to the a-lifebrook greenway um Jay Fills raises a concern about paving so much and taking out a lot of grass along the river um I guess I would just say you know there's we're trying to improve the path that's already there make it accessible and as we've talked about previously we had some we heard about the need or concerns about faster cyclists on the path and then providing a space for them on the road um I don't know if you want to add anything more to that just to add that you know the the bike lanes that are proposed would fit in the existing roadway cross sections so no added pavement there unless in the long term we would kind of build these these up to a different level but um generally that's you know existing pavement um and then just back to Dan's point about trying to make an accessible path down in the parkland space um another thing I would just say to that is we really want to make sure that people of all you know abilities ages um user types get to have a great experience and so providing this paved path that goes through trees that you know has more of that woodland experience gets away from the road um was something that we really thought was worth the extra pavement so um and again there there are um there is a question specific to this and to the materials in the survey so you'll be able to say whether you support that or not and provide extra comment thanks um I have two maybe that we go to john and Kathleen unless you have a really good clarifying question that might change our understanding I have two final questions but one needs clarification and the other I think is fairly simple um Steven just asked about the vehicle level of service at summer in mystic with the diagonal crossing or maybe Lucy can answer that yes so this the existing conditions of this intersection is level of service d and that's and I'm looking at the peak hour I think the am peak hour morning peak hour is better but the worst condition that we looked at was the afternoon peak hour the existing level is d as in dog and it's a scale of a through f with this change because we will be giving more time to pedestrian so a bit less time to vehicles it goes down to e and that means it's a one letter grade drop there's like it's all based on vehicle delay so it means the delay increases enough to bump it by a threshold so what that means is it what probably be noticeable but not extreme because it's one level it's still very much e is very much acceptable and very common in urban roadway network so it will be a you know probably a noticeable change but not extreme and you know it's a and I think I know there's a question about that on the survey as well is that a trade-off people would be willing to take for providing that safety and again it's really important to provide enough time for people to walk all the way across even slower walkers and it's that's what requires the extra time thanks okay yeah I think thanks amber for moving us along somebody cooks in the kitchen here yeah let's go to john thanks yeah I think the this what you have on the screen now um is is and I'm a you know primarily cyclist but I think the that turn in front of the police station uh is is probably the the of all the things I've seen that I like I think that's the one thing I would I would say might be the most problematic for for the town and for traffic is is eliminating that that turn from from summer on to mystic in front of the police station because that the the flows of larger sort of like metro flows of traffic not just Arlington but the way in which people circulate through Arlington I think that that's that's one that that we may have to you know go on the side of the of the automobile but the the main thing I wanted to ask about or sort of bring up is if you could go to the the the standard cross section that shows the yeah actually the other one sorry yeah the one the larger one with the the broadest one yeah so the no the cross section but yeah yeah so I really am concerned about guardrails in terms of both wet if you if we switch to a a two-way bike lane on the on mystic valley parkway as well as as it goes up and I think you've you've you've done a good job sort of channeling the traffic on on the the incline on the hill that goes sort of like between the lake in the cemetery but when it comes to the sort of standard flow of south side of the river until you get to the rotary and then you switch over to the north side of the river to continue into to Winchester so that section in Arlington on the south side of the river I really worry about about having just a sort of raised raised cement or something and actually having a guardrail of some sort and then later when you see it in plan it looks like you've you've just treated it with with like you know pavement marking it's sort of like it kind of looks like like a wing in a few different areas yes exactly that right so so this this this here in plan is is probably where I'm most like talking about and I think there's a good example of what could be done kind of behind the center of town where the if you're going if you're on the minute man bikeway and you're you're from the intersection we were talking about earlier and you're headed out toward Lexington or you're headed into town there is a guardrail between like the parking and the and the path and and there are a few openings in that guardrail I think the guardrail might actually just be out of of wood as well but there's a few openings that could kind of line up with some of the discussion that people have brought up about access points but I would really want to see a guardrail and it could be again aesthetically pleasing of some sort because this is not supposed to have commercial traffic anyway but but I think that that having a guardrail of some sort if we have two-way traffic because if I'm flying on the road I'm fine with with traffic the same way but when I'm going contraflow to the traffic it with also bikes coming the same way I would I would feel much safer with with some sort of like hard guardrail in between thank you yeah I would I would say in general we've heard a few different comments on what is the level of vertical separation from that lane so we're gonna definitely be getting that more thought and be talking to the stakeholders about it Kathleen hi Kathy's husband actually can we bring up the summer and mystic intersection please uh so we're parents of two young kids uh we have gone through Arlington Center with a six-year-old on her own bike with a two-phase crossing I vastly prefer the configuration on screen uh the Arlington Center it worked within the design constraints of the grant and the funding available it single phase is the way to go if you're going to be supporting you know all all abilities all ages you can't have kids queuing up in the middle of the street regarding the Harvard Ave intersection with the mega crosswalk there I'm really afraid that's just maybe full of cars uh at a red light they're just they're just going to pile up there they don't they're not going to obey that stop line 50 feet back from the corner uh and then uh finally regarding uh Kimble Road and Davis uh you said they were not well planned out but I want to put a buck in your ear about this we already have cars coming down Kimble Road uh trying to use that goat path of a connection to get on mystic valley parkway and they're doing that because on google maps it looks kind of like the road continues so it would be helpful in some future configuration if it did not look like the path continued straight down uh in the mystic valley parkway just and we there should also be consideration given to preventing cars from trying to just uh drive over the the bike path because that already happens in town at other intersections all right um that's it thank you thank you yeah those are those are great points that can kind of turn into recommendations for implementation Steven hi thank you um just uh if you pull up the summer and mystic street intersection just responding to the comment about the slip turn lane i'm not sure what the technical term is but as dan is probably aware there's you know existing the same kind of condition at the intersection of route six sixty in mystic street and it's extremely dangerous um and it really needs to be reconfigured and i think a lot of that happens here as well having that separate turn lane that cars don't look for pedestrians i live very close to here and walk across that intersection all the time that turn that slip turn lane just feels extremely dangerous in the existing configuration so i think this is a great improvement from just pedestrian safety perspective thank you linette and just want to note you know we're going to be kind of wrapping up in nine minutes but anybody we don't get to in the chat please know that we're seeing your comments and saving up these chats go ahead linette yeah i'm a walker and a runner all year around several times a week down um along the path next to lower mystic lake and i'm every time i go down there i'm absolutely shocked that the the guardrail is next to the lake protecting cars from going into the lake but meanwhile the pedestrians walking through the along the path would get plowed down by the cars but the guardrail isn't actually there to protect pedestrians it's there to protect cars so i would like to urge that that guardrail gets moved so it's protecting pedestrians thank you not uh i have one more question but then there was a previous one that i didn't quite understand uh since i don't see anybody else raised hands we can see if we can try to get that clarified um if that's all right that is fine i've got a few more i think just comments in my chat as well and maybe another question um but go ahead dan uh so this is from jeana s and i i don't quite understand excuse me i don't quite understand this about the rotary crosswalk back for safety re knows in but what about cars zipping out of the rotary and the safety of pedestrians jeana do you want to clarify that sure um the the term knows in was was was presented as a reason why the crosswalk was was pushed back but that's for cars entering the the rotary then there are the cars that are exiting the rotary and that's where it's even more dangerous that's why most of us cross in the middle of the bridge so that the cars that zip around and go out of the rotary have some time to stop before slamming into us the pedestrians i can offer a little um thoughts on that this is a you know illustrative concept but one of the key things that the way these roundabouts will operate will be very different than they do today because there's actually a much narrower vehicle path right now the that brown area doesn't really exist itself pavement and cars can go through straight through at much higher speeds than this will allow so the whole operation of the vehicle all the way through will be much slower and then the idea also is that the um vehicle approaching the stop bar will be out of the way of the rotary roundabout circulating traffic when it stops for the pedestrian and generally if they're well designed to keep that speed really low which is really the key thing cars have very good yielding behavior it's correct that probably entering the roundabout is even a little better than exiting the roundabout but it's really all about keeping the speed low the visibility is good because you have a good line of sight so thank you thanks Gina thanks um I have okay question and then a comment so we'll this may be the last question so for Mary uh let's see for the roundabouts we'll stay on the roundabouts how do you envision cyclists navigating with the new design is the concept for cyclists to use the crosswalks or merge with traffic and take the appropriate exit as is done now and the the answer is both can be possible and more confident riders that are more comfortable in traffic and riding at a higher speed would will often choose to ride in the travel lane and just take a full lane and ride through but there is going to be a accessible route that's accessible to bicycles for the less confident riders and to go all the way around and they would use the crosswalks so it'd be kind of a shared crosswalk with bikes and walkers thank you and I guess I'll just read the comment I have from Mark about if the major intersection crossing could be triggered with buttons just like lakes whoa so we just sent a very long comment yes so that the crossings could be triggered with buttons like the lake street crossing that would greatly improve traffic flow and competency for reduced lanes especially during rush hour so and then I have a very long comment from Emily but I will not read but we will record it um I think I have one more question here um or maybe two why was the convergence of bikeway at summer street at food link 108 summer street never considered as an access point from the bikeway in this plan I I don't know yeah I know where that is I know where they're talking about um that was not all I can say is that was not considered because it's not the fastest route to getting from it's actually west on this on their plan farther west by you know 500 feet or a thousand feet or something so yeah that was um simply not the fastest route really actually getting to the bikeway probably through buzzle field as the fastest route but mill street is the next you know sort of the next best and I think that um in my opinion I don't know why you'd go to summer street if you didn't or go to the summer street near food link access point if you didn't have to um so it makes sense to go to mill street the summer street access point is also having to cross there kind of mid block I think would be less comfortable or more difficult than trying to cross at the the intersections that we already have so I've got a last question here and there were a couple other comments I appreciate them and we are noting those is the vision that bikes won't be able to use the parkway on lower mystic lake from route three to route 60 you can bike much faster on this section than you then would be appropriate for a shared use path you can certainly bike in the roadway so they're talking about the constrained section and nobody's going to prevent a cyclist from doing that we are not providing specific infrastructure for that we thought about it we did try to plan it out the roadway widths just really don't make that possible it becomes particularly complicated to get up and down this hill and how that would work um because you just can't provide for both directions um so you're either riding in the roadway which a confident cyclist might be able to do also I will say we're narrowing the roadway so it it will help slow traffic down I know that's very intimidating now because it's just a wide open sea of payment um but we'll be narrowing it considerably um and then you will have the path to the side for more casual users those are the last of the questions that I had were there any other questions from from yours Jan um I think a question that um sort of a question indirect question um it was about the slip lane at mystic and summer street uh maybe this is a question for Lucy do you know I think there was data collection taken there was it able to capture those right turns from the slip lane from summer on to mystic oh definitely and we have a count of all movements including the slip lane great and we're you know and all that traffic's included in our analysis of the design and you know there will still be a right turn lane it's just not going to the right turning traffic will be at a lower speed which actually will be a safer situation than what exists today and that will be in the existing conditions memo that we referenced earlier right yes yes that should be released the traffic counts are all in there right so people can dig into that data yeah we've hit our meeting time I really want to thank everybody these were great questions and some great comments again if if we didn't say yours we are noting them in the chat I just re-entered the link to the survey please take the survey um and you you will be able to comment there as well on all of these different components any any final words Dan or Amber we'll be releasing the survey tomorrow or the next day and it'll be open for next two weeks I want to echo Stephanie what you said really appreciate these are great comments and questions and definitely fill the survey and share it with everyone we want to get a lot of feedback so that we can move forward to have a really robust study to continue on and make this project a reality Amber anything you want to say no I think I think you covered it and you know there's a lot of considerations we're trying to balance here with environmental concerns and access and it's tricky and we're doing what we can to try to take all the input into account well thanks everyone for your time have a good evening the remainder of it okay go to bed good night thank you everyone


Thank you for coming to the session. I'd like to start the architecture of the Microsoft brand action based on the distributed consensus with Kubernetes. My name is John Peniston. I'm working for the Hitachi in Japan and this is my first time experiencing and enjoying international conference in English, so I'm a bit nervous, but I'll do my best. In my experience, I have developed a web solver network patch and your application solver like GlassRidge for 10 years. Instead of that, I created a modern addition plan for our customer. For example, infrastructure change like the on-premise system to the public cloud. And now I'm researching the developing a microservice transaction system. Today, I'll be presenting consensus on transaction comments so called Paxos Committee. This paper was written by two famous people. First is Dr. Jim Gray, who is famous for the relation of database technology. And second is Dr. Leslie Lampard, who is famous for the distributed consensus algorithm Paxos. We are developing a microservice transaction system applied Paxos Committee for cloud native customer needs. Today, I will introduce the practice to implement a Paxos Committee in the Kubernetes environment. This story originated from the difficulty of achieving the distributed transaction with microservices, so I will explain in this order. First, microservice and distributed transaction challenges. And second, cause of the inconsistency. And third, theoretical approach to prevent inconsistency. And fourth, and last, Paxos Committee operation in the Kubernetes. Are some of the engineers, sorry, what is the microservice activity? This is a way to develop a system while dividing several small applications and according to the business responsibility boundary. This way causes easy understanding service and engineers can improve system policy story and engineers can choose the best technology for the each services. But sometimes engineers may have first difficulty in architecture microservices, particularly in data management. Engineers would like to implement a microservice in their enterprise system because of the needs of the system majority. And business data agility may be necessary in some cases to increase overall system majority. So split the business application and data in the database according to the responsibility boundary and make it a service. The database for service pattern is a famous way to split the data in microservices. As a result, database began to be distributed. And updating data in the database to DB increased the risk of the inconsistencies. And what is the inconsistencies? I describe the example of the inconsistencies. When the transfer service transfers money from the bank A to bank B. And bank B will draw the money by the bank account and bank B deposited the same amount of the bank B account. And this scenario, if bank B cannot deposit the money for some reason, like a failure, inconsistency happened between the bank A's amount and the bank B's amount. The famous way to prevent this type of inconsistency is so-called distributed transaction technology. But when engineers construct a distributed transaction system in the microservices, we found the problem that the system will be complex. Please look at the graph. This is a result of the solving on the stack of our engineers. Many engineers think that the complex distributed transactions are challenges and the top of the concern to construct a transaction system by the microservices. What is the complex distributed transaction? The Microsoft's textbook, Microsoft's partner with example Ninjabur, includes the benefit of the microservice and the challenges of applying the global transaction management to the microservices. It mentions DB must be ex-compliant and cannot show the modern DB technology as a noise QL. And second, technology stack is limited to the famous framework that include the transaction monitor, such as the Java EE or Spring. And third, consistency must be given up to some extent in the distributed system from calf searism. Therefore, while citing the semantic paper, he mentions the man of achieving the distributed transaction in user application. To resolve the inconsistency problem, SAGA design is the most famous approach in the microservice architecture. SAGA links the business process together in the workflow. As the process fails, a compensation transaction is called to counsel the update and ensure that the misty. But please look at the core sample of the business application. With his implementation of the transaction management and routing the business rule, as a result, the business application become complex. Why is it complex? Why is it complicated? That is because three inconsistencies factor in the distributed transactions are very complex event. There are three main causes. First, business error. Second, system failure. Last, right, right conflict. The first step of the complication is the update is prevented by the business validation in the DB. It will prevent this update. For example, with the rule more than the maximum balance or out of balance, it will be necessary to counsel service that have already been updated. To achieve this operation, we have to implement the compensation transaction in the application logic. The second step of the complication. For example, when the process goes down during the transaction execution, the transaction state will be lost and inconsistency will happen. To prevent the inconsistency by system failure like this, the persistent mechanism needs needed. But failure handling is also a challenge. Failure can occur at various times and how to set the transaction depends on the case of the error. That's the code to deal with the numerous error will be exposed to the application logic. And the last step of the complication is right, right conflict. For example, if multiple transaction interfere with the same account area, updates will be overwritten and inconsistency will occurred. To prevent this inconsistency, concurrency control is needed. The lock is the type of the concurrency control and the lock information itself becomes a state. The lock information must be the persistent. After that, the code to deal with the concurrency control will be exposed to the application logic. Please look at the picture below. What we originally wanted to do was simply to have the two service updates. When distributed transactions are implemented, there's three factors complicate the application and its first structures. This is the root cause of the complication of the transaction management. The saga itself has only business error capability and cannot deal with the failure and right, right conflict. In particular, the saga is seriously flawed when it comes to the right, right conflict. Therefore, no matter how hard we try, we cannot prevent the inconsistencies. There are already established mechanisms in the academia to prevent the right, right conflict in the distributed transaction. That is the principle of commitment ordering paper from 1992. These papers say that the only mechanism to prevent the right, right conflict in the distributed transactions are to phase locking or avoiding cascading abort. And saga doesn't have this technology. Today, I don't mention the detail, but and this is this academic opinion. However, many microservices engineers don't know the fact why. We think that academic affiliation is fragmented. Microsoft services boundaries to like Chris Richardson prefer to cite a semantic asset and the saga paper, but failure and right, right conflict solutions are inadequate in these papers. On the other hand, there's a faction that's considering how to prevent failure and right, right conflict automatically. In the fraction, there are commitment ordering paper and distributed consensus for the failure paper. For now on, we'll explain what happened when we implemented theory by this faction. One of the techniques in this faction is the two-phrase commit, which is called the anti-pattern of the Microsoft seeds. Two-phrase commit provide concurrency control. Two-phrase commit requires a lock during the DB update and locks release after the agreeing atmosphere. This is so-called two-phrase locking.  This is the so-called atomic commitment. The two-phrase commit has two merits for the engineers. The first is to prevent inconsistency by the right, right conflict. And second, the exposure of the transaction control faction to the application can be very small, at least one line like a JTA atomic transaction. This reduced business logic coupling. We first attempt to reproduce the mechanism in the Kubernetes environment. We have tried to implement a separate transaction management architecture shown here. I apply my prototype atomic transaction annotation as a library to the transaction application on Quarkus. A prototype JD-DVC driver is applied to the bank application on Quarkus. From there, the resource manager process is launched as a side code for the bank app and transaction manager is started as a separated pod. The transaction manager and the resource managers are building the glass fish and JTA transaction info was used to make them independent. First, atomic transaction internally numbers the transaction ID at the same time as transfer API is accepted. Then the transaction ID is allocated to the rest API head of field and passed around. Trans service code bank will with the API and bank be deported API after the API call. The transaction ID is pressed internally to the JD-VC driver in the bank services. The JD-VC driver internally passed the transaction ID and updates SQL to the resource manager. The resource manager process updates SQL to the DB. In addition, before the update, the SQL is locked by the set for an update. When the DB update is finished and the control is returned to the transfer service, atomic transaction and post-processing is executed prepared to the transaction manager. After that, the transaction manager sends a prepared to the resource manager. After that, atomic commitments to start. The DB returns updates availability like a prepared OK or an ID to the transaction manager. If all returns prepare OK, the transaction manager sends a commit to the resource manager. If even one prepared NZ is found, the transaction manager sends a route back to the resource manager. At the same time, the transaction manager passes the result of the atomic commitment in the transaction log. After that, DB released a lock. The transaction manager responds to the result of the atomic commitment. This method keeps the application simple. Nevertheless, this two-phase commit has well-known weaknesses. That is a single point of failure problem of the transaction manager. In particular, the transaction manager process is down in the atomic commitment phase and the transaction state is lost. DB lock is not released and spontaneous rollback breaks the atmosphere. This is a common note as a futuristic hazard. To prevent a futuristic hazard, it is necessary to deal with the system switch operation of the past system stage called primary backup. However, IT fragmentation can easily occur in the crowd environment. If fragmentation makes it difficult to prevent a futuristic hazard, there are two reasons why the crowd environment and primary backups are incompatible. First, primary backups use the fencing equipment to switch systems. But the promise for the primary backup is the fencing equipment must be able to receive the failure notification immediately. In an environment such as a cloud, sometimes the failure notifications delay and the system does not switch over.  Therefore, the mechanism to overcount the single coordinator's single point of failure will end up having a single point of failure. And by taking a counter measure against it, the system will gradually become dependent on the hardware. The crowd varies to abstract the hardware from the software stack. But if you increase the dependence on the hardware, there is no point in the building the system in the crowd. I will discuss it from the theoretical aspect of computer science again. There is a so-called failure model in academia. The model describes the severity of the deal with the IT system failure. Saga and two threads commit can only operate in the failure-free environment. Primary backup is a protocol that works properly in synchronous fail-stop. That is an environment where there is no communication delay or break up. The crowd is in an environment where the infrastructure is hidden and distributed happen communication delay sometimes. So it is very difficult to apply Saga and two threads commit on the primary backup in the crowd by academic theory. And two threads commit is a theory before the crowd is popular. So new theory needs required to construct a distributed transaction in the cloud native system. That is to incorporate the consensus in the failure environment theory. The Dr. Lampot and Dr. Lynch have worked on. In other words, we adopted products such as Paxus or Raft, which can raise the consensus even in the distributed failure environment. Let me explain what Paxus is. Paxus is a consensus mechanism is using a Google Spanner for the multiple database replication and blockchain ledger replication. What is the consensus? Consensus means that the group of the multiple participants obtain a single result. This is a bit confusing. So I will use an example of the parliament system of the Greek island of Paxus. In the parliament democracy, the process of enacting a law is the submission bill to the parliament discussed by the members and majority board and agree or rejection. The parliament system on the Paxus island is unique in the original Paxus paper, the part-time parliament, the secretary and the legislator or part-timers. The secretary had their own ledgers, but the congress wants to have a single vote result for the bill. So it is necessary to have a consistency among the ledgers. In order to achieve this consistency, Paxus incorporates a mathematical theory into the parliament system and the communication of the legislator. Please look at the vote process in the Paxus island. Legislator 1 makes an agree proposal. Then, each of the legislator votes against the proposal. Another legislator 2 may make an off-site proposal and all the legislator will finally converge on the agreement through a consensus process such as a discuss. Then, secretary 1 records the result to the ledger by the majority world and now the legislator and secretary on the Paxus island are part-time and so there is a possibility that the some secretary and legislator will go home after the vote is over. If the secretary lives with the ledger, the result of the vote will be lost. On the other hand, there is a desire to keep track of the vote result even after some people have left. What should I do? You can vote again and another secretary can record the result of the vote. The majority world so-called quorum mechanism works here. Even if one of the five legislator lives, the previous vote result and later vote result will be the same. In other words, if one process is down, but the majority of the process are still alive, consistency can be assured. This is not not the pigeonhole principle and the mathematical theory. It is very difficult to explain, sorry. If you are interested in this theory, please look it up. So where should this Paxus mechanism be mounted? A simple solution is to replace the primary backup storage area with no SQL implemented rough to a Paxus or something. For example, storing the transaction log in the Redis. But this approach is not efficient in the term of the number of communication for consistency and transaction termination. It is extremely efficient to implement the Paxus at the atomic commitment. The problem with the heuristic is the aggregates the updateability and the resource participating the distributed transactions. If this is a primary backup, it will be delayed or not switching the crowd. That's a pride of Paxus-Iran Parliament system to the atomic commitment. Resource prepare updateability makes the input for the Paxus protocol. The richer process to the prepare OK and the voltage token after exiting the Paxus protocol finalize a commit to a logback. Since the results have a fair lot to rely on standard availability, even if one legislator follows, a commit to a logback can be finalized immediately. Let's look at an example of this using the Kubernetes. The characters are most the same as the two friends commit, but in the low left corner, please place the redundant cogenitor in the port. We'll prepare it as a port for the port for the bank B. Here we will first update the DBA. This update process is not really different from the two friends commit. And next, send a prepare from the transfer service to the site called the bank service. At that time, the site can create a box to collect the consensus supporting result and the transaction state of the bank services. Next, the DBA returns a prepare OK at this point. The site calls for the transaction state as a prepare OK. After that, the site call of the bank here broadcasts this prepare OK to the redundant cogenitors. The redundant cogenitors persist in the updateability like a prepare OK bank A in its own volume and cogenitors send the updateability to the site call branch of the bank B. This means that the bank B site call now know the updateability of the bank A. Branch one of the bank A and branch two of the bank B are both prepare OK. So, the bank B service finalize a commit state to the DB. The redundant cogenitor for the bank two send the updateability of the bank B to the site call of the bank A. And that's the same. Even if one of the redundant cogenitors go down, if the majority of the cogenitors are still alive, the friends can commit immediately. And if redundant cogenitors act more, the cogenitors are already crossed to the 100% and the probability of the furious hazards can be as close to their percent as possible. And the current implementation, the redundant cogenitor is pushed into the single pod. But if the cogenitors are geographically distributed or rearranged, it will be possible to provide like a disaster recovery and so on. Now, to summarize, there are multiple challenges to achieving the distributed transactions in the microservices. First, implementing transaction management complicated microservices systems. And second, technology stack is limited to the framework that includes the transaction monitor, such as the WEOS spring. And third, consistency must be given up to some extent in the distributed system from the capitalism. And last, DB must be excellent and compliant. Regarding this first issue, it was confirmed that the Atmack transaction can be used to describe transaction boundaries simply. The second issue is that the separation of business application and transaction controller will allow us to solve the problem. We have standardized the API interface between business application and transaction controller components. For the standard, we can create a library in the language such as Go or JavaScript that works the same as Atmack transactional. And it starts from the CAP series. The issue, the consistency must be given up to some extent in the distributed system. And that all CAP attributes can be guaranteed by the Paxos. What does this mean? The CAP series, CAP congestion is a hypothesis that the distributed system can not satisfy consistency of our ability and partition tolerance all at the same time. And in the crowd, our ability and the partition tolerance are important so consistency is ensured by the eventual consistency. In contract, we have been following the Google or Dr. Lynch's academic proof of the CAP. If the partition does not occur, both consistency and the viability can be achieved. And partition really occurs in the real system, even if it does occur. Paxos can prevent the lack of consistency because Paxos provides a redundancy and wait for the commit during the partition occurred. And when consistency and the partition tolerance are required, 100% of viability cannot be achieved. However, redundancy can bring viability as close to 100% as possible. In other words, using distributed consensus algorithms such as the Paxos were roughed or something, in effect, consistency and viability and partition tolerance can all be satisfied and simultaneously. The first and the final point, we still consider the issue that the DB needs to be the acceptable compliant and that more than DB such a node as here can be selected. However, this issue can be solved by the putting a transaction wrapper on no SQL, like the scurral DB or cherry Gaussian paper approach. In other words, the Microsoft transaction problem can be solved by using all of today's technology. If you encounter any of these crowd or Microsoft transaction challenges, please contact me. I'm sure there are many areas we can solve. That's all for today. Thank you for hearing about my extension.