Tree Impact On Development

I love trees, but man they can sure ruin a good development site. Four key elements to consider when assessing trees, and how they may or may not impact a site include 1. Species 2. Health 3. Location 4. Size.

Tree Impact On Development
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I love trees, but man they can sure ruin a good development site.

Most Melbourne Councils apply overlays to entire regions that restrict owners’ abilities to lop trees on their properties. These include Environment Significance Overlays (ESO), Significant Landscape Overlays (SLO), and Vegetation Protection Overlays (VPO). Each can kill the prospects for profitable development projects.

You can learn more about Victoria Planning Provisions here.

Given how important trees are to Councils, and how dramatically they can impact development potential, all developers must devise a way to quickly and accurately assess them.

Four key elements to consider when assessing trees, and how they may or may not affect a site, include:

1. Species 2. Health 3. Location 4. Size

The Species of a tree, and how Healthy it is, are the main factors used to calculate its Retention Value in the eyes of Council (high/medium/low). Now, I’m woeful at determining Species  – heck, I have trouble differentiating between an Oak and a Pine – and, I’m equally useless at judging tree Health. But, this article isn’t about these elements, which are best left to qualified Arborists.

This article is about how to effectively map the Location and Size of trees in the first instance, in order to rule the site in or out for further investigation.

I recommended a development site to a client a few weeks back. It consisted of 1740m2, in the Activity Centre Zone of a suburb, I rate highly. We were considering it for 12-14 terrace townhouses. The problem was, it had some massive gum trees on it which could dramatically reduce the development footprint. I went about plotting the Location and Size of each one.

First, using the dimensions from the Title (available within the Contract of Sale), I sketched out the property on a piece of paper.  It’s important to leave enough space on all sides of the paper so that you can plot trees on neighbouring properties as well – never forget about neighbouring trees, because you have no control over them (although once a neighbour kindly offered to remove a troublesome tree at one of my developments, to which I kindly offered him a few hours work on the excavator).

Second, I attended site with a long and short tape measure, and began plotting out the rough location of each significant looking tree… Tree #1 is 3.2m from the right boundary and 5.6m from the front boundary; Tree #2 is 2.1m from the right boundary and 7.1m from the front boundary; etc.

Third, I measured the circumference of each tree at 1.4m high, then the circumference at the base. These are the two measures that you need to determine the Tree Protection Zone (TPZ) and Structural Root Zone (SRZ). Check out this really helpful site for a variety of calculations and insights on trees: Treetec

Fourth, I took photos of each tree. If one or more proved particularly troubling, I could always text one of my arborists for a quick opinion on Species and Health.

Lastly, I went back to my office and consolidated all information into a sketch. The collective impact on the development footprint was profound – the TPZ areas amounted to about 30% of the site!

Always share your sketches with Council. A bit of civility and respect can lead to surprisingly useful information.

I put together a Mud Map of ideal townhouse locations and sizes and overlayed on it the location and TPZ of each tree. Even allowing for a 10% encroachment into each TPZ (typical allowance from Council), there was no way we could build what needed to be built in order to make a profit. But, I took the drawing into Council anyway.

We had a good chat about the area, and what we had in mind to address some of the pent up demand from key demographics.

“I could really use your thoughts on how best to navigate these trees… Is Council more flexible about trees on such a prominent development site?

It turns out that this Council had a blanket policy designed to protect against bush fires. It wasn’t widely known, and it certainly wasn’t promoted to developers, but the policy is simple: any tree within 4 meters of a boundary, or within 10 meters of a habitable dwelling, can be cut down without need of a planning permit. “Any tree?” I asked. “Yes,” she whispered as though she wasn’t supposed to share the info, “Any tree”. You ripper!

All of a sudden, the site stacked up.

I checked with the selling agent, and the vendor was OK with a condition that allowed us to lop specific trees prior to settlement, at our expense, and at a time agreeable to her. Getting rid of the trees ASAP meant that our land survey wouldn’t reflect them, nor would the Arborist Report.

We were unsuccessful at auction, unfortunately, against a fellow that simply wasn’t going to stop, but the key lessons remain: do what you can as a layman to determine the location and size (TPZ and SRZ included) of each tree, and their potential impact on design and feasibility; discuss directly with Council; seek formal advice from an Arborist if any specific trees are of particular concern.

One follow up note: Never, ever take down a tree without a permit.

I sat through a VCAT Hearing last year, relating to a property we’re trying to develop. A massive storm rolled through Melbourne a couple of months prior and one major tree of concern snapped in half. I took photos immediately following and kept my receipt for the Tree Man. About 20mins of the hearing was dedicated to this specific tree because my story (while true) clearly appeared dodgy. Dialogue between my Representative, the Council Representative and the VCAT Member made abundantly clear to me that NO DEVELOPMENT PERMIT would be possible if I had taken it upon myself to lop the tree and cop the fine.

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