Week 11: Sanitation, nutrient limits and choosing between options
The nitrogen the garden cannot absorb, and how to choose between the alternatives.
The household excretes far more nitrogen each year than its garden can take up, and that gap is the constraint that caps every site. You size excreta and greywater systems against your home's storage band, build an uptake-limited nitrogen balance, and find a destination for the surplus. Where the course's design rule is stricter than the law in your client's jurisdiction the page says so and says why — and you cite your own jurisdiction's actual greywater instrument rather than the course's rule. Canberra leads, and pays for being cold. The second half of the week is the comparison itself: the existing condition against three alternatives in one grid, dominated options marked, and the cheapest arrangement that meets the client's targets identified before anything dearer is argued for.
This week
- Lecture, 17 May 2027
- The nitrogen has nowhere to goWeek 11 — sizing excreta and greywater systems, the uptake limit that caps every site, and the greywater rule that is the law in a state none of you is in
- Tutorial, 20 May 2027
- Where the nitrogen goes, and choosing between the optionsWeek 11 tutorial — size excreta and greywater to your site's band, find a destination for the nitrogen surplus, then build the options grid Assignment 2 turns on
- Assessed, due 21 May 2027
- Tutorial Completion Checkpoints20 % of the course mark. Ten small outputs, one a week from week 2 to week 11, marked on a good-faith attempt rather than on being right — the work that makes the two assignments possible
- Worked example
- CanberraThe Taylors' home leads this week, because its climate makes this subsystem hard. All five homes are compared on the lecture page.
What you leave with
A nitrogen balance with a destination for the surplus, and an options grid with the dominated options marked.
You have finished the tutorial when all of this is true, and you can tell without asking anyone:
- your chamber capacity matches your site's WHO storage band and you can say why the band differs by climate
- your nitrogen balance shows what the garden absorbs and what leaves, with a destination for the surplus
- your greywater scheme meets the course design rule
- you have cited your own jurisdiction's greywater instrument and stated where the course rule is stricter
- your options grid compares the existing condition with three alternatives and marks the dominated ones
Assignment milestone
Week 11's material is examinable in quiz 5, which is sat in week 12.
Where this sits
With the measured year in hand you size, cost and compare the options, then argue for the one you recommend — the cheapest arrangement that meets the household's own targets, plus an honest case for any dollar spent beyond it.
Expected effort
About 8 hours this week: 2 h lecture and notes, 2 h tutorial, 1 h preparation and quiz, 3 h assignment 2. The assignment hours go into: Three options built and compared; dominated ones struck out.
A planning guide from the semester planner, not a requirement and not a measurement of anyone. Tutorial submission sits inside the tutorial hours and the quiz inside preparation; neither is counted twice.