Treatment on Small Lots

As homes are built on smaller and smaller lots, wastewater design can get complicated fast. In this episode, we’re joined by Bill Hensley, Senior Systems Engineer at Orenco, to talk through the realities of designing treatment systems for tight spaces. We cover site constraints, soil challenges, regulatory considerations, and some creative solutions that make small-lot development possible. 

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Transcript

00:08

Hello and welcome to Make It Clear,  a conversational podcast about all things related to water and wastewater.  I'm your host, Angela Bounds, and I'm joined by my co-host, Shawn Rapp.  In each episode, we'll tackle a relevant topic with facts and expert opinions and make things clear. 

Angela: Hello and thank you for joining us again. Today, we're going to be discussing small lots. So as

00:37

More and more building occurs around the globe. We find ourselves building on smaller and smaller lots, trying to get the biggest bang for our bucks, putting homes in places that maybe were unbuildable before. And so today we've got Bill Hensley with us. Hi Bill. 

Bill: Hi there. 

Angela: Bill is, I believe, one of our longest standing employees.  How long have you been with the company now?

01:08

Bill: 32 years. 

Angela: Yeah, a very, very long time. 

Shawn: Just a few more than me. 

Angela: Just a few.  Just a few. There aren't that many of us anymore that have been around that long. So thanks for being here. Bill is also what I consider one of our biggest success stories. So Bill started out in the shops building stuff. I think we may have talked about this before if you've been on the podcast.

01:36

We in the sales department, some of us would literally transfer calls out to Bill in the shop every time someone called about siphons.  Cause he was the one who would troubleshoot them and, and make the magic happen. But now he's in, in sales. And what's your current title? 

Bill: So I'm one of the senior systems engineers.  So I actually went.

02:02

back to school for engineering after I was in the shop. When I started at Orenco, I didn't even really know what an engineer did. So when I started building this stuff, I was like, this is interesting. How did they come up with this stuff? 

Angela: How very engineering of you. 

Bill: That kind of sparked my interest. 

Angela: Very cool. And you work predominantly in the international region, correct?

02:29

Bill: That's correct. Yeah. So pretty much everything outside of North America will… most of those will come across my desk. 

Angela: Yes. Yes. All over the globe.  (Bill: Exactly.)  So Bill's going to talk about small lots with us today. So let's go ahead and dive into the questions and get some answers. So Bill, when you're dealing with a small lot,

02:58

what are the first  three things that you want to know about the site that you're building on?

Bill: Great question. Well, you know, there's a variety of questions that we probably want to know right off the bat. And some of those are going to be dependent on the location that we're working in.  And some of these things are based on hard knocks that I've learned over the years.  (Shawn: Right?)

03:28

So, you know, my first thing that I ask or I wonder about is, is this new construction or a replacement system?  Of course, if it's a replacement system, we may have existing infrastructure and buildings that we've got to figure out how to work around.  Is there any possibility that the local municipal sewer system is going to be coming through at any point?  And if so,

03:57

will the homeowner be required to connect to it?  Because that could potentially save them a lot of money being able to plan accordingly.  How large is the house?  How many bedrooms?  So we can start getting an idea of how large of a treatment system that we need potentially.  Are there site plans showing the existing buildings, driveways, setbacks?

04:26

topo lines, wells or springs and any other existing infrastructure that we might need to avoid like water lines, heritage trees or plants. And like I said before, the existing drain field location. Sometimes people want to use as much of their existing infrastructure as possible. So having an understanding of like how old is some of that equipment, like their septic tank, for example. 

Angela: Yeah, is it still watertight.

04:56

Bill: Exactly. 

Angela: Have we tested it to ensure that it's still watertight? Like, what are we looking at?  Is it sized appropriately? Yeah. 

Bill: That's exactly right. Also looking at for like new sites, you know, how has the site been evaluated to determine the type of soil classification and the perk rates, because that's going to come into play for the designer.  And on those small lots, will the homeowner

05:25

get a size reduction if they used an advanced wastewater treatment plant.  That was a case I ran into on my little lot that I had a failed system on. I needed to go to an advanced system because there's no way I could put a traditional system in there. 

Angela: So are regulators generally open to alternative technologies for small lots?

05:52

or do you find yourself having to educate them?

Bill: So in my experience,  I've found that some regulators… there's generally a list  of pre-approved systems  that they like to defer to.  But when you have another option, you'll find those that on occasion that they're happy to be educated about new options that are out there.

06:21

And they can give you some direction about ways to pursue perhaps trying to seek approval for that system. Of course, it has to be properly vetted and researched and have all the proper documentation to do that.  

Angela: So can you tell us a little bit about what kind of system elements like the materials of construction, dispersal system, et cetera, tend to work best for small lots?

06:49

And do they bring any trade-offs? Like, is it a little give and take? Like, what are we looking at? 

Bill: Well, you know, it kind of depends on the location.  For example, regarding discharge options in some areas, some regions I work in, they don't actually even use drainfield systems. They use soak aways or they use deep well systems because they just don't have the area to put drain fields in. (Angela: Yeah.) That’s pretty common in some of the islands.

07:19

In other areas, they really prefer some type of pressurized system, whether it be laterals or drip line systems.  And then in others, you might run into some that really prefer doing gravity discharge drainfield. So it really all kind of depends on the site. And in some instances, the preference of the designer and maybe the regulator is evaluating the property.

07:48

Angela: Do you run into many soil issues when you're working on islands?  

Bill: Yeah. You know, in a lot of the areas that I work in, they will have very, very shallow soils. And so very quickly we run into shallow bedrock, sometimes limestone, things that really difficult, can be difficult to excavate and install equipment.

08:17

And because we don't really have a lot of soil to get kind of that tertiary treatment, then getting really good advanced treatment before we discharge can be really critical because we don't want runoff polluting the natural estuaries or really what makes those places so popular, the beaches. You don't want to have issues there. 

Angela: All right. So what are some of the non-technical issues

08:45

that can make or break a design for a small lot?

Bill: Well, of course, you know, having sufficient rooms first and foremost, know, also, you know, you might have a lot that is looks like it's sufficiently sized, but if it's a really steep lot, it might limit what you can actually do on that lot. So the terrain... 

Angela: What’s the what's the smallest lot you've ever seen?

09:11

Bill: Well, I've seen lots that were a fraction of an acre. I don't know exactly what the size is. Like you might be talking 0.2 acres that are pretty small.  And you know, really that's probably one of the smaller lots that I've seen. 

Angela: Yeah. Yeah. Putting a drain field on a quarter acre lot.  

Bill: You have to get…

09:38

And when you also start looking at, well, you have these minimum setbacks. Your drain field lines can't be closer than X feet to a building or to your… or to a well or to a fence, your property line that it really can start getting very, very tight and limited. 

Angela: And that's on a flat quarter acre. (Bill: Yeah.) That's not that's terrain at all. 

Bill: Exactly. Yeah. So sometimes when you start getting in

10:05

terrain, that's where things like maybe drip irrigation starts looking good.  Or you can have some of these flexible lines that you can kind of run horizontally with the slope. 

Angela: Yep. All right. So last question, maybe. So what are some things that you wish that planners, installers, or realtors understood better about on-site on small lots?

10:36

Bill: Yeah, I think thinking about this again, learning through some hard knocks, you know, are there any potential plans for that neighborhood to be annexed into the city? Knowing that up front. If so, how likely is that to occur? How far out is that likely to occur? Because, you know, whatever you're going to put, whether you're going to be connected to a municipal sewer system or whether you're to be doing an onsite system, it can be quite expensive. (Angela: Yeah.)

11:07

Also trying to make sure that if this is a site where a wastewater treatment system is going to be installed, really having a pretty thorough understanding about the costs associated with those, because there's generally a variety.  And understanding not only some of the capital costs, but the long-term operating costs and the life expectancy of those systems is something

11:36

that would really help the homeowners or developers to make wise decisions on the direction they may need to go. 

Angela: Yeah. Understanding lot development.  Right? Like, understanding that impact that an onsite system has on lot development. 

Bill: Yeah, that's right. 

Angela: Yeah. It can help you develop lots that are not otherwise able to be developed.

12:05

But there are considerations that have to be taken in. 

Bill: Yeah. Sometimes, developers will want to have a small lot as possible so they can sell more lots. So in some of those instances, there may not be enough room to put an on-site wastewater treatment plant and dispersal system. We do run into those. 

Angela: Yeah. But they could always set aside like...

12:32

So that doesn't make onsite a non-starter necessarily. It just looks different, right? That's where you can use effluent sewers. You can put a tank at the house and not have to put a dispersal system and carry it away. But then you're having to set aside property to disperse on. 

Bill: That's exactly right. So then we start looking at options. Does it make sense to do onsite treatment and then discharge to a common

13:02

irrigation system or does it make sense like you said to use on lot septic systems and pump just the treated effluent down to a shared wastewater treatment system? 

Angela: Yeah. There's lots of stuff to take into consideration.  (Bill: Absolutely.) It's not just a one and done one size fits all answer. (Shawn: Right.) 

Bill: That's exactly right. And I think that's what

13:28

kind of makes what I do interesting because there's a lot of variety of what you could do, but what makes the most sense for the customer that you're trying to assist? 

Shawn: Do you have some examples you could share with us? 

Bill: Yeah. I mean, we had a project and I was working on a project design in Australia, for example, and they had some very steep terrain that they were working on.

13:55

And they really only have one place that they could put an irrigation system. So in that particular project, what we ended up proposing was that each of these small lots have their own individual wastewater treatment system.  And then that treated water then went down to the bottom of the hill into a shared community irrigation tank. And from there, they were able to use that water.

14:25

The point with to be able to use that water for green areas. 

Shawn: Oh, okay. 

Angela: There you go. (Shawn: Yeah.) All right. Well, anything more that you want people to know about small lots?  

Bill: You know, I've seen some pretty interesting things that people have done that have pretty restricted lots. I've seen where people have put wastewater systems in their basements.  

Angela: Oh, yeah. 

Bill: I've seen where they maybe put it under decks.  (Angela: Yeah.)

14:53

So, you know, there's ways to get inventive. And so I think that's kind of nice for people to know that, hey, even though you have a small lot, doesn't mean there's not anything you can do. There's usually where there's a will, there's a way.  

Angela: You just have to ensure that there is access.  Yeah. I've seen it put under a deck and with no access.  I've seen them.  I've seen a tank. I think I've talked about it before. Half under a

15:23

patio and you couldn't access it. 

Bill: I had one of those. (Angela: Yeah.) And that's a house that I bought. It was a real pain because I had to go diggin’ all this stuff up and remove some of the existing infrastructure they had just so I could make it accessible.  

Angela: Yeah. That gets fun. All right. 

15:51

Well, thank you so much, Bill, for joining us and thank you all for listening. 

Bill: It's my pleasure.  

We want to thank you again for joining us today.  Before you go, don't forget to subscribe where you listen to podcasts so you're notified when new episodes are posted.  Also, you can leave your comments or suggestions through the contact link on our website, www.orenco.com.  Until next time, have a great day.