Board of Commissioners - Regular Meeting

stormwater master plan presentation yes okay so uh first off i'd like to go ahead and apologize in your packet there was several packets of information included to include a rating sheet as well as a cip summary sheet and then the in the individual project listings and going through that in advance of this presentation was able to note that there was one project that was missing that was very integral to the overall planning in the Soundside Road area. And that was the third phase, which basically connects three other projects together. This was presented previously to the board and it had a pumping station noted at the intersection of Deering Street and Soundside Road. I think Commissioner Vaughn had commented. that property in that area likely would not be available for that, so we looked at an alternate location to the north for the siting of that pump station, but it was inadvertently left out in the packet that was in the board packet, and this information that I'm giving you today reinserts that back in there. It does not, materially change the overall priority, but it coincides with the other projects in that way. So I just wanted to start off by stating that. Okay, so, The overall stormwater master plan, that framework has included many different items to include an asset inventory and assessment, which has been completed. There was also a public workshop, which we had last August. There is a geo database management and dashboard. I think that was previously presented to the board earlier this year. an asset condition assessment that was completed as well and also part of the work that was included was a hydraulic analysis along south memorial avenue which is one of our main drainage trunk lines within the town and this analysis looked at identifying any deficiencies within that network and improvements that could increase the level of service from either a one year or two year and try to increase that up to a 10 year level of service. Also, what we're gonna talk about today is the capital improvement plan project prioritization and scoring. And then also in the works is a watershed action plan, which is part of the overall scope of work. And that will really enable us to focus in on grants, not only just related to stormwater, but also along the estuarine shoreline. And lastly, all of this is going to be combined into a final report, which we would like to go ahead and bring back to the board at your November meeting, which ties all of this together. All right, so just for the prioritization summary, there is 22 project areas that were prioritized. They were evaluated based upon scoring that ranges from zero to 75. highest scored project was the ramp one outfall which is in South Nags Head and that came in at 64 points and the lowest scoring was one of the phases of the Dune Street improvements which was phase 2b and that scored at 40 points but most all of these projects scored between 55 to 45 points and Really the lowest cost projects with the highest number of residents Really those were the ones that were scored the highest All right, so included in your packet and included in the information that you have before you is a summary table which prioritizes and ranks all of the 22 projects and along with the score and the cost for each one of these projects. And then there is also a graph which goes through the ranking for each one of the projects ranging from that 64 as a high to the 40 as a low for Dune Street Phase 2B. What we have up on the screen is an overall map of where all these project areas are located. You can see we've got a high density of projects from the north end of town up along Memorial Avenue. all the way through the whalebone junction and then in south nags head down at ramp one and you can see that it really does encompass primarily all of the all of the town addressing many issues that we have seen historically and some that we've seen more recently that have validated that we continue to have problems in some of these low-lying areas so the the criteria that was used for scoring was through a scoring matrix and this is uh... uh... matrix that that town currently has in stormwater management operating procedures it looks at uh... items like flooding frequency flooding impact existing system condition uh... water quality benefits associated with projects uh... maintenance the number of residents impacted uh... safety the sources of blood it could be rainfall based it could be over wash uh... with consideration for that uh... any constraints that may be associated with the project um budgetary concerns the location whether it's within a town street a private street or within the north carolina department of transportation right-of-way and then lastly flood reduction is looking at the reduction in flood time and recession and all of those were assigned there was three different scores for the rating for example for flooding frequency you had frequent had a score associated with it occasional and infrequent And then there was a weighted percentage that was applied to that item. And so these were looked at for each project, a score assigned, and able to go ahead and develop the overall ranking for each of the individual projects. so go through this uh... as rapidly as possible you've got the sheets included in your packet and this these are the individual rankings for each one of the projects uh... the ramp one outfall which was ranked number one project out of the twenty two projects identified uh... it's got a cost of eighty five thousand dollars associated with it uh... it's got the prioritization parameters and their associative scores and the total score in comparison to some of the other projects it falls on the lower level of cost it's got the highest number of residents impacted because of the west side ditch that spans from about James Street all the way down to ramp one, that was one of the major contributing factors to the high ranking. The frequency of flooding down in that area, the need for maintenance, and also the need for safety, because a lot of the flooding that we see is within the roadway surface, and that leads to safety concerns associated with vehicular, circulation throughout that area. uh... south memorial avenue as i had noted before there was a hydraulic analysis done on memorial avenue and it identified some improvements throughout that corridor and the highest-ranking one was up in the admiral street uh... area now this is broken out into two parts sidewalk improvements um that are ongoing that will continue this fall that we were able to go ahead and take care of a portion of these drainage improvements with that work And this would be the second half of that work, which spans along the east side of South Memorial Avenue from Admiral Street and proceeding northward. And that would be really upsizing the existing storm drain system within that area. And the cost of that is about $180,000. It's got some low site constraints. It's got some safety improvements. And also just the number of residences in that area that are impacted by drainage and this being a critical segment for that, that this led to the ranking of number two overall of the 22 identified. the third ranked project is soundside road phase one we've seen that here most recently with rainfall runoff and extensive ponding along this corridor that this would comprise of putting in a 36 inch diameter trunk network which would span from the very south end of Soundside Road up towards the curve where we have existing infrastructure. This is a relatively high cost project at $750,000, but due to the frequency of flooding and the number of residences impacted, as well as other factors, that this was ranked number three out of the 22 projects. the uh... for three project is deem street phase one uh... that's another project where we've seen flooding at the intersection of south virginia their trail indian street with a pretty high frequency and so this would be potentially the first days of a three-phase project uh... where we could go ahead and we could capture some of the runoff most of this runoff uh... which is seen from the adjoining shopping center to be able to go ahead and capture that and infiltrate that locally. This has got a medium level cost. It doesn't have as many residents impacted by it, but because of the frequency in flooding and the safety concerns with the flooding at this intersection, it ranked number four. South Memorial Avenue. that again as part of this overall network and the number of residents that it serves along this main trunk line. This is in the area of East Baltic Street. And this would be increasing the existing pipe size of that storm network in order to increase that current level of service from a one-year storm to a two-year storm in some case, and a ten-year storm on the outermost pipes for this proposal. Some of these projects you'll see they'll receive the same ranking and that is because they both achieve the same score and so You'll see that in the summary list and that's noted on each one of these individual sheets so East Epstein Street is an example of that where this is ranked number four with the South Memorial Avenue project This is a relatively low cost project. This finishes off some of the work that we started along South Virginia Dare Trail back in 2019 and this will go ahead and connect from Epstein Street down to the north side of Town Hall and then also continue on over to Fire Station 16 and make some improvements there since this is part of an overall network Within the village that starts at Seven Sisters and then flows all the way through the village through the golf course and out to the sound and so it's it's important to Have the downstream part of this network in place prior to making upstream improvements otherwise If you don't do it within that sequence, you'll continue to have flooding at the upstream ends. I The next project is Memorial Avenue. This is identified as area one, and this is a relatively low-cost project, and this is upsizing some culvert pipes at select residences just south of Atlas Street. There are several of the culvert pipes at that location that are undersized, and this would be upsizing and bringing more continuity to the overall drainage network. The eighth ranked project is West Lookout Road. This is an area over in the Northridge subdivision, especially during large rainfall events where they've had some significant flooding back on these residences. And so this is a high level of residences impacted. It's got some high constraints because there's also the potential for backflow from the west side ditch along 158. And it will have some increased maintenance needs associated with it. And the cost for this project is approximately $340,000. Also ranked eighth is the Seven Sisters subdivision. And as I had noted before, the focus would be on the downstream improvements first before you could see the impacts for the Seven Sisters subdivision. This is a subdivision where most of the building pads are up high and the road sits low. So after a rainfall event of two or three inches, you'll see some pretty extensive ponding within that subdivision. It does flood at a pretty high frequency and so with the improvements that we've made and then also with the one scheduled for Epstein Street that we could see some major improvement with the installation of a storm drain collection network to be able to drain out this subdivision after a rainfall event. uh... also great number eight is south old road phase one this is a another street that's on the south side uh... off of uh... lakeside ad that uh... floods with the pretty high frequency and this could be part of a phased approach and so the phase one would consist of installing a drainage network in this area that could be made up of perforated sock pipe that would aid with infiltration in this area and Improve the level of service from what is currently being seen after a rainfall event also ranked eight was a well-known junction area uh... this is a and area that we see with a pretty high frequency of flooding a lot of standing water especially in the area of the dune burger and the surrounding area and so this would be an attempt to go ahead and formalize that network with connections to an existing ditch network That has existing conveyance out to the sound through the catfish farm This is a relatively high project cost and only a minimal number of residences that would be impacted But this could make a major improvement in that area Which I had noted does flood at a pretty good frequency We've got Memorial Avenue, area number three. This is a low-cost project. This is near the intersection of Bonnet Street, and this is essentially just the replacement of a single pipe in order to increase that level of service. project rank number thirteen is bucking your drive this is also over the northridge subdivision this is very similar to the to the lookout truck project in that it has low-lying areas at backs up to the west side digital one fifty eight And this would take a very similar approach with the improvement of infrastructure within this area and then conveyance out to the 158 ditch and the addition of a backflow preventer to ensure that we don't solve a problem and create a problem at the same time. uh... caroline excuse caroline in circle uh... is also ranked number fourteen this was on the previous stormwater master plan uh... did not move forward this would take a look little different approach than what was previously proposed and this would be the installation of a storm drain collection network that would tie into the existing drainage network out at one fifty eight The estimated cost for this is approximately $425,000. This area does flood occasionally, but especially when we have significant rainfall, we do see extensive ponding back in this area. Also ranked number 14 is Soundside Road, phase two. And this is the area in the South Ridge subdivision. When we had our public workshop, we had several homeowners from this area along Ridgeview Way who had talked about some of the issues back there. This would be improvements that would extend from Ridgeview Way out to Soundside Road and connect up to the existing infrastructure there with Soundside Road phase one. so some side route wrote these three is the uh... is the pumping station which we previously had at the intersection uh... deering street and some side road relocated this northward uh... to uh... undeveloped parcel that would connect to the existing infrastructure from from South Ridge and from Soundside Road and be able to take that, pump that over to two undeveloped parcels along Soundside Road. This is a pretty expensive project due to the cost of property purchase. And that cost is about $1.8 million. But what it does is it connects the two other projects plus Deering Street to provide a comprehensive drainage solution in this area. And Deering Street, which was ranked at number 17, that This is a relatively low cost project and it would be the installation of or the restoration of swells and the installation of some storm pipe in this area for conveyance to the Soundside Road system, which then is connected up to the pump system to be able to provide some relief in this area. Also ranked number 18 is West Blue Jay Street. The cost for this is $270,000. This is a medium project cost. And this is the function of topography. You've got some very high elevations to the west that intersect there at Blue Jay Street and Pamlico Ave. And so by going ahead and capturing that runoff, minimize the impact to some of those lower-lying residences there on the south side of Blue Jay Street South Old Road phase 2 this was previously discussed as a potential second part of the phase 1 improvements and this would be a pretty costly project because this would tie into the existing infrastructure at Old Road and then it would use, it would incorporate a pump station and then pump out to several undeveloped parcels out by 158. All right, and lastly, we've got Barracuda Drive, which is ranked number 22, and this takes three different areas. This takes an existing issue out at Mackerel Court, with some lower-lying elevations to be able to capture runoff, as well as Salmon Court and then near the intersection of Hesperides and Barracuda Drive to be able to capture that roadway runoff in advance of being discharged onto some of the adjoining properties. And a lot of this is just a function of topography. that we've got some really high elevations we've got water that flow is pretty rapidly through there and being able to capture and try to infiltrate that locally so it minimizes any impact on the adjoining residences you have to excuse me I that slide was out of sequence because we still have the last two are dune street phase 2a and then 2b and then this could be a second and third part of dune street where the second part would include the installation of a storm pipe collection system spanning from the intersection of dune street up to an existing ditch about a quarter mile to the north of there that ditch then connects up to the 158 roadway network and then to the soundside road drainage network And then 2B would be a project that would include, as needed, the purchase of a parcel, an undeveloped parcel there at the intersection of Dune Street and South Virginia Dare Trail and utilize that as an infiltration area if needed as part of the other improvements with the Phase 1 and Phase 2 eggs. Okay, so the key findings with all this is the ramp one outfall, that ranked number one, followed by the Memorial Avenue area two, and then Soundside Road phase one. Those rose to the top just because of the fact of the frequency of flooding, the number of residents it served, and the lower end of the cost. the typically these projects scored higher as the cost decreased and so that in conjunction with the fact that you had a lot of surrounding residences that were impacted by it they had a tendency to go ahead and score higher So next steps in the process is that we would like to receive any board feedback as to the ranking for these projects. What staff would like to do is once we receive the feedback, we would like then to refine the priorities and then try to pair those up with other project work that we currently have in our CIP over the next five years. Similar to what we've done in the past and then we would come back to you potentially at your fall retreat with that refined list to ensure that we follow that approach that we've taken over the past four or five years and And then lastly, we'd like to go and present the final report to the board here in November that encapsulates all the work that has been done associated with the stormwater master plan. There's a lot to cover there. And just any initial thoughts or feedback, we can have some time for you to go ahead and try to digest it and share it with the town manager if you'd like. But if there's any initial thoughts that you would like to share that maybe something seems out of place or something that we should start to look at sooner rather than later. Thank you, David.

Any immediate questions?

I have a question. With properties that are bordering waterways, like the Sound and maybe Ramp 1 on the ocean, why was no ranking given to water quality? They all have a none for water quality.

So for ramp one, that would include the installation of a backflow preventer at that location. And that doesn't have any treatment associated with it. But what that can do is that can eliminate the ebb and flow of water through that ditch system. which we see that consistently we don't have that here in the north end because there are some backflow preventers on some of the northernmost outfalls samsai road conk street curlew street as well as gallery row and so there is there's since there's not a specific treatment mechanism associated with that we can't say that it qualifies for water quality benefits i see okay

Okay. So flooding, for instance, on Soundside Road or Old Road, you're saying because it's not going to be treated for water quality, we can't count it as a water quality project. Is that what you're saying?

Well, currently as presented. And so these are just looking at the stormwater aspect of it. Now, if we get to phase four for Soundside Road, there's going to be a water quality benefit to that. since we're using infiltration practices, which are natural practices that can filter out pollutants and sediment. But when you look at the three other projects that it's connected to, that those are just... Those can have a water quality benefit through infiltration, but if the ground is saturated, it starts to lose that water quality benefit. And that's a lot of what we've seen here recently.

Okay. And then another question I had for those same projects, Soundside Road and Old Road. The flooding source was only rain, but I think both of those sites would flood from tidal water as well. So is that not factored in?

I think it was on some side.

Overwash? Overwash, yes.

Yeah, not title as much as overwash.

Right?

Yeah, so overwash and title influence should be considered for both.

Okay.

I think so. I have kind of a general question about the relationship between phases. So the value of one phase now and say we never got past phase one or two, how is that accounted for or is it just, I know it's accounted for in your mind,

There are different ways that we can approach this. If we were able to go ahead and secure some grants that we could look at these more collectively and we could knock these out all as a single project. But also looking at the cost of each one of these projects, is that it may not make it feasible to incorporate that into our annual cip so we just try to make it a little bit more digestible and that we can look at this in time and just spread those funds out over a period of time to incorporate these improvements and the soundside projects

For them all to really work, we need to get to that last one. Or for them to work well?

We need to get to the third phase.

The third phase. So I get off fighting it off, but if a future board decides not to do the third, those first two are kind of...

There is, so I think the critical component is going ahead and getting in the infrastructure for that phase one.

Okay.

Once you have that in, then you could swap out phase two and phase three. So you could go ahead and put the pump system in then and then all the subsequent phases you could go ahead and connect up to it.

Okay.

So there is some flexibility with each one of these phases and it doesn't lock you into a certain sequence. And it just gives us more flexibility to be able to adapt because we, My experience is we always change things up based upon the current conditions. That could be because of funding, that could be based upon other factors, but just trying to give ourselves the most flexibility to be able to work within the framework I think is what we're shooting for.

But ideally if we start fighting into the sound side projects, we would want to have the plan long term that we would be doing all of them.

yes and and i think the other thing too is with that watershed action plan it does um open a cell ourselves up to additional grant opportunities that we can go ahead and pair with some of the eastern shoreline work if you want to qualify for some grants you're probably going to have to do phase three

because that has the water quality benefit. And the water quality benefit is what gets the money.

And the other phases probably make us more.

So that one might be one that you bundle together, even with the resiliency project on the shoreline. Yeah, I was going to ask about that. And that's probably how we would look at it. And as David was mentioning, you know, this prioritization of this stormwater projects is looking at this kind of singularly in a vacuum, but we're not gonna look at it like that when we do our CIP. We're gonna look at how these tie together with the other streets projects, like overlay work, paving work, waterline work, and then we're gonna have to put things in order based on what we can accomplish, you know, financially, but also what we can get grants for, and so, The one thing that I noticed about this is that once you get past the first couple of projects, the scores are so close together that you can really move them around because it's not like one has a drastic benefit over another. And so that's helpful when we go to do the CIP because we're going to be opportunistic in the CIP. we need to move a project up because we only have that much money that year then we'll do it if we get a grant for a project and we're gonna combine it with some other work we're gonna move it up And so we'll try to do our best to come up with a plan for the CIP for the next five years, but then the board always looks at it every year. And so it ends up being an iterative process, even though we try to do our best. You're going to move things around, and that's what we've been doing with the sidewalks, with the streets over the years, we've been doing that. And then David mentioned, retreat and this is something we've been talking to the board about you know we're going to have to sort of build this into our financial model as well and figure out like the funding levels we need to do what we want to do our hope is to try and model that for the board so the work can say okay we want to be able to afford to do x y and z and so that's how much money we're going to have to figure out how to come up with to do that and then the board can settle on that, because that leads into revenue and taxes and things like that.

And with the phases, our grant eligibility probably increases if we're proactive with the other phases.

Yes, I think, but like the water quality benefit, I think, because when we, with the grants we've gotten so far for a lot of these projects, like RCCP and Land and Water Fund, David mentioned the Watershed Action Plan, they're going to be looking for a water quality benefit for those grants. And so just doing a flood control project might not make a score as high as if you include a water quality component. And I think that's the purpose of us doing the Watershed Action Plan, is to position ourselves for those grants. Thank you.

That is correct. And really the intent of the scoring was to go ahead and look at this in an objective manner, noting that sequentially this may not play out like this. We've seen this on prior master plans where we've had to go ahead and adapt based upon other project work that we could incorporate this into. This was just an exercise to go ahead and come up with a ranking, noting that there are other factors that may take a little bit more weight to go ahead and shift things up. But like the town manager said, the scoring is so close on so many of these projects. It's like, you know, you can go in many different ways.

It's a little scary, too, when you see these numbers. But I've seen previous plans where it was worse than this. But every time we get into the two-year budget and we start putting these projects in a two-year budget, I think what typically happens is these are very high-level looks at these projects. Once David gets a hold of it, then he can start to really refine these projects into something that's manageable And so it's always evolving. No, it's a very comprehensive plan. It is. My question was about funding, but both of you kind of answered that for me, so I appreciate it. I appreciate it.

Yeah, this is very helpful. And scary.

I wanted to say one thing, and David and I talked about it, because obviously it started raining right when David started speaking. But what we've been dealing with the past week with the rainfall, and then obviously last week with the Conk Street area, we had an issue. and largely with the outfall, but that is probably an area that does need something, and it's not in this plan. And David's response to me was, well, we can't keep doing everything along NC-12 just in a vacuum. We've got to involve DOT and get their participation. And so I think that's really what our goal should be, however we can do that. David's already engaged them about the outfall and what's going on there. But I think that that may be something that we look at, maybe separate from this plan. And if we have to eventually come up with something and incorporate it into this, we can. But, you know, really getting them to sort of take the lead on some of that stuff. And you can see on here, you know, you've got... Virginia Deer Trail in the village. You've got Virginia Deer Trail at Dune Street. I mean, we're already proposing to put piping along a lot of the Virginia Deer Trail as part of this plan. So...

Yeah, we had the ability to log a lot of time out there by the Conk Street intersection here recently and see how that system works. Yeah, there's definitely room for improvement there, but there are some things that people don't always notice is the influence of groundwater rise, especially during frequent rainfall events. We're seeing a lot of that throughout town. And we've gotten numerous phone calls from here in the village, South Nags Head, not so much in the north end of town. But when you have month of July, we had 15 days of rain out of the 31 days. South Nags Head, I think, got hit the hardest and then as you progressively went north it it was not as severe as some of the other impacts that we've seen throughout town but groundwater rise especially during saturated conditions limits our ability to infiltrate infiltration is our main way of managing stormwater runoff and conveyance is Really plays back up to infiltration and when infiltration doesn't occur then that's when we really have extensive flooding throughout our area And we were able to observe the conditions post rainfall and just really see how much groundwater plays into some of the localized flooding but it's been helpful that we've had our groundwater wells because it really gives us an indication of how much that groundwater comes up over a period of time connor shared some data here recently it was thursday friday we had back-to-back storm events we saw the water table rise two and a half feet over that period And what I don't have a sense of, because it's been very difficult, there's been more rainfall events after that, but it stayed up pretty high, and it's starting to come back down, but every rainfall event we have after that, it keeps on going back up. And that's primarily what we're seeing in these here recently that's led to a lot of concerns from a lot of people in this area that, hey, I've never seen this before. I can't recall in recent history having this amount of rainfall over this time period with this frequency. I can probably recite the rainfall that we had back in 2016, 17, and 18, back in 2012, back in the early 2000s, but I don't recall a pattern like this. especially in the south end of town, which has got hit the hardest and the central part of town that we've had this for this frequency of rainfall without having the availability to recover and Until we get that drying out period in that recovery period. I think we're still going to see a lot of this water persist and

It would be, especially if there's more to it than what you just expressed, because that's pretty fascinating. Some of our learnings from our wells, I think. I think I would love to hear some of that. Me too. I'd love to hear a presentation about that. I think that would be fascinating, what we're learning from that. I'd love to see a presentation in one of our meetings.

Yes, and I think just trying to figure out that recovery time and how long that takes, that's important to know, too, so we can go ahead and set up an expectation when people come across these conditions what that recovery time may look like.

One thing I just want to add, and I was planning to bring up on the commissioner's agenda, was I think we've all heard from a lot of people, and we've seen a lot on Facebook about stormwater and people see ponding water, but I have also heard a ton of praise for our staff. You guys have been very visible over the weekend with Conk Street. I know you guys probably hear people complain more than anything, but... I think that a lot of residents that have seen the changes over the years and the leaps and bounds Nags Head has made in stormwater is apparent, and I just want to relay that because I have heard so many people reach out that have seen you guys working on the weekends in the rain at Conk Street. I've seen it. I've seen the improvements, and other people have too. I know we constantly have new challenges, but it's clear that we're taking them on, and we're very, very proud of everything you guys have done.

Well, thank you. And I think from what I've seen in the north end of town where we've made some significant improvements, we're not seeing that reoccurrence of flooding, not to the levels that we've seen in the past. We've got some improvements down in South Nags Head. they're probably not as quick as people would like it but we have seen some improvements and i think that's important especially long term when you have saturated conditions that you're able to go ahead and drain that off and so not only aesthetically does that look better but you know you don't get the mosquitoes you don't get the the ground water mixing in and having that brown water standing for an extended period of time so

This is also a great time to remind people. I know a lot of people have been pumping because the water table is so high, but it's a great time to remind people about the water credits that we offer because from what I've heard from Jimmy, they've been pumping like crazy from alarms going off and stuff, and just getting ready for that next rain, it's a good time to pump your tank and get ready for it.

Yep.

All right. Well, bye.

Cool. Good point. Excellent. Great. Thank you, Dave. Thank you, Dave. Appreciate it.