Long-Term 1999 to 2045 capital spend on water
This post tries to identify when the margin of error in long-term planning increases over time due to random and political changes.
Long-term planning for water can date fast. In the 2015-2045 (30-year) plan for Hamilton City Council (HCC), and the Cranleigh ‘Business Case Analysis for Water Services’ done for HCC in the same year, the highest budgeted cost for year 2027 was for installing universal water meters. In the 2024-2034 long-term plan (LTP), the priority for year 2027 is now for investment in an Infrastructure Acceleration Fund (IAF) reservoir to allow 4,000 new homes in the CBD. The 2015-45 30-year plan was out of date in just over half a decade, and the 2018-2028 plan prioritised an ‘upgrade of the water treatment plant’ over ‘replacement of water mains’ in 2021.
The 1999-2019 (20-year) plan’s largest investment for 2010 was ‘future growth’, while the 2009-2019 (10-year) plan project called ‘renewals’ [maintaining what we have] had a higher priority for the year 2010. The 2009-2019 and later long-term plans set different priorities than the 1999-2019 plan. I suggest that the 1999-2019 (20-year) long-term plan was a worthy ideal, but people should expect capital investment to be unreliable after about a decade.
The issue can be seen again with the 2015-2045 (30-year) long-term plan. Projects in the 2018-2028 LTP have a much higher cost and in the 2021-2031 plan the cost trend is travelling in the opposite direction to the 2015-2045 (30 year) plan. The change in priorities happened within a decade.
Economies of scale – From the 2006-2016 plan, when Hamilton had a population of 131,000 and an area of 98km2 (1,337 people per km2), the inflation-adjusted graph does not appear to show a benefit of spreading the cost over more people. This is unlikely to change until after the $236m ($305m inflation adjusted) new water treatment plant is funded in 2045.