Phase 03 — Site analysis

Upload the levels plan

The base plan with the datum marked, every spot level annotated against it, and the scale and date on the sheet. A photograph of a hand-drawn sheet is fine if the numbers are legible.

Where your datum is, and what it physically is

Specific enough to find it again in two years — "galvanised nail in the north-east corner of the front porch slab", not "near the porch". Pick something that will not be dug up, paved over or moved.

The value you assigned to the datum

An assumed 100.000 m is standard practice and keeps every reading positive. Use AHD only if you levelled from a Landgate benchmark or a surveyor gave you one.

Grid spacing you used for the spot levels

Tighter on a small or broken block, wider on a flat one. Note it here so you know how much you are interpolating between points.

The spot levels

Every grid point, plus every door threshold, every boundary corner and every existing drain, pit or gully. Name each point so it matches the mark on your plan.

The base plan with the levels marked on it

Scale, date, and where the drawing or file lives. Say how the datum and the levels are annotated on it.

What the levels told you about the block

Fall across the site in mm and as a percentage, which way it runs, the high and low points, and anything that surprised you.

Record the results for each test area on your block

One row per zone. State whether the pH is a water-kit reading or CaCl2 — they differ by about 0.7 units. For depth, note what stopped the bar: limestone, coffee rock or compaction.

Which areas will need the most amendment?

Worst first, and say what each one needs — wetting agent, clay and organic matter, ripping, or rock breaking per pit. These are the numbers you price from in Phase 7.

Upload the sun and wind overlay

The base plan with true north marked, the shade outlines for 9am, noon and 3pm, the hot west-facing surfaces, and arrows for the sea breeze and the winter storm wind.

Where the overlay lives, and when you walked it

File name or folder, plus the date and the season. Shade recorded in August is not the shade you get in February.

Summer and winter sun paths, as drawn on the plan

Sunrise and sunset bearings and the noon altitude for 21 December and 21 June. Get your own from SunCalc or the Geoscience Australia calculator rather than a generic Perth figure.

The areas in shade at 9am, noon and 3pm

The hottest surfaces on site

West and north-west facing walls, limestone retaining, colorbond, light paving, the pool fence, the shed.

Prevailing summer sea breeze direction

Draw it as an arrow on the plan. West-south-west at onset, backing to south-west at full strength — mark where it crosses your boundary.

Winter storm wind direction

North-west quarter, off the Indian Ocean. Watch two or three June fronts — note which gates slam and which corner collects the rubbish.

Upload your marked-up services plan

Show the sewer line and access chambers, the water main and meter, power, gas, comms and every retic line and valve, with the depths you potholed.

Your BYDA enquiry sequence number and the date you lodged it

Plans come from each asset owner, not from BYDA. Allow up to two business days, and lodge again if the scope changes or the validity dates expire.

Every service you located

A row each for the sewer line, the water main and meter, overhead power, underground power, gas and comms. Depth is what you measured when you potholed, not what the plan implies.

Sewer access chambers and inspection openings

Where each one is and what it constrains. They must stay accessible and at finished level, so they set your paving levels as well as your plan.

Existing retic — lines and valves

One row per station. No asset owner has a plan for this, so run each station off the controller and trace the wire to the solenoid.

Your marked-up services plan — scale, date, where the file lives, and what marking it up revealed

Name the thing that surprised you. That is usually the constraint Phase 5 has to design around.

Add your audit photos

Every element you have given a verdict — plants, paved areas, structures, retic heads — plus the lifted pavers showing the base, and the existing controller program before you change it.

Every significant plant

Everything over knee height. Species or a photo reference, condition out of five, and the verdict. Most established Perth plants over 1.5 m are KEEP or REMOVE, not RELOCATE.

Every paved and poured area

One row per area. Judge the base, not the surface — say which you are rating. "REPLACE the base, KEEP the pavers" is a legitimate verdict, so write it that way.

Every structure and edge

Retaining walls, fences, patios, sheds, decks, pool barriers, garden edging, steps. Anything built rather than grown.

The retic system, station by station

Never write "retic works". One row per station, plus rows for the controller, the mainline and the bore or tap if you have one.

Upload the plan

The flattened sheet — constraints in red, opportunities in green, hatched zones for areas, with a north arrow, a scale and a date on it.

Where the drawing lives

File name and folder, or where the paper copy is kept. One line, so you can find it in Phase 5.

Scale it is drawn at

1:100 on a standard block, 1:200 on a big one. Check the north arrow is on the sheet.

Date on the sheet

Site analysis has a shelf life. A neighbour builds a two-storey and your shade layer is wrong.

Every constraint marked on the plan

Services, easements, setbacks, shade, root zones, poor drainage, hot walls, overlooking, access limits. One row each, and the annotation should carry a number, a time, a direction or a depth.

Every opportunity marked on the plan

Good views, sheltered corners, existing mature planting, level areas, winter sun. This is the half that gets skipped.

What showed up once it was all on one sheet

The collisions — which constraint sits on top of which opportunity, and what that is going to cost you.