Elevation lismore: 12m
Nearest water need: 120m elevation on western side of great dividing range.
Not many, if any, water sources are nearby water need sites where a pipe or man made diversion takes water through geographical barriers such as mountain ranges.
Extreme case study.
Mediterranean to saharan artificial inland sea with canals engineered with controlled nuclear blasts.
https://en.m.wikipedia.org/wiki/Project_Plowshare
https://en.m.wikipedia.org/wiki/Sahara_Sea
https://geology.com/below-sea-level/
Free flow of salt water. Angle needed
To allow adequate drainage of the surface, the recommended minimum grade or cross-fall for a pavement is generally 1 in 100 (1%), or 10 mm per metre.
https://www.ccaa.com.au › C...
RESIDENTIAL Concrete Driveways and Paths - CCAA
200km viaduct would require 2000m elevation drop at 1% fall.
Lake eyre 9500 km sq at average depth 3 m (guesstimate) below sea level/ max is 15m
Volume in m3 is 9500*1000*3=28.5 million metric metres of water or 28.5 billion litres of water.
A man made pipe from the ocean to Lake eyre at its closest point is approx 600km at a 3m fall rate the drop is less than 0.000005% not enough to overcome tunnel material construction friction.
At a pipe size of 3m diameter would have a 7.5 metre area capacity at a maximum flow rate of 2m per second would be 15m3 per second which is 473million m3 per year.
So a 3m diameter pipe would take 28.5m m3/ 15m3 which is 330 days to fill at a zero annual evaporation rate.
The evaporation rate would be 2.5m per year at Lake eyre.
This means that only .5 of a metre water depth would be added each year or 6 years before sea level achieved.
https://www.stateoftheenvironment.des.qld.gov.au/climate/climate-observations/evaporation-rate
https://en.m.wikipedia.org/wiki/Pan_evaporation
Evaporation rate lake eyre 2.5m per year.
https://www.awe.gov.au/water/policy/national/lake-eyre-basin/about