This hub spans three unrelated field disciplines that happen to share the outdoors: recreational and small-craft boating, broadacre farming and grazing, and environmental/water-quality assessment. The people using it rarely overlap — a skipper planning an overnight anchorage, a grower calibrating a spray boom, and an environmental officer modelling a river's oxygen sag all land here for different reasons.
Passage planning and boat performance
Use the speed/distance/time and knots tools to plan an ETA, hull speed to sanity-check a displacement boat's realistic cruising pace, fuel burn to size your range, and distance to horizon for visibility and sighting checks.
Anchoring and ground tackle
Reach for the scope calculators when you need to work out how much rode to let out for a given depth, tide and bottom — the rode & scope version adds chain/rope and freeboard so you can plan total length carried, not just ratio.
Cropping, spraying and seeding
Use the spray mix tool to convert a per-hectare product rate into tank quantities, and the seeding rate tool to set drill calibration from target plant population — both hinge on getting your paddock area and rate units right first.
Water, grazing and farm storage
Pick stocking rate for carrying capacity, rainfall volume for what a catchment or roof yields, dam volume for storage on hand, irrigation volume for what you've applied, and evaporation loss for what open water is losing over summer.
Environmental and water-quality screening
These are first-pass screening estimators: RUSLE for soil-loss risk on a slope, Streeter-Phelps for downstream oxygen sag below a discharge, plume travel time for how fast groundwater contamination migrates, plus turbidity-to-TSS and acid mine drainage neutralisation for load and dosing estimates.
