The risk of spill in the Campaspe system at 10 September 2022: 40%
This value represents the percentage of years that spills occur from GMW’s share of Lake Eppalock taking into account the current storage volume, storage releases, inflows and evaporation from the storage using the historic data available.
Note: 10% or lower is the threshold for a declaration that would return water quarantined in spillable water accounts to allocation bank accounts.
Volume needed to fill Lake Eppalock at 1 September 2022: 109,080 ML
Click here to find the current volumes in Campaspe system spillable water accounts.
Ranked historic inflow to Lake Eppalock: June - August
Description and Tabulation of the graphical content inflow to Lake Eppalock: June – August
A bar graph titled Ranked historic inflow to Lake Eppalock: June – August is on the page above. X axis label “% Probability of Exceedance” which spans 99% on the left to 1% on the right. Y axis label is “3 month inflow – units megalitres (ML)”. Significant highlighted data in the graph is the inflow for the June – August 2022 period is indicated by the red line: 52,514 ML.
Each % probability of exceedance is reported from 99% to 0%. The general nature of the information presented is low inflow values of less than 10,000 megalitres have a high probability of occurrence. Less than 10% probability of inflows above 194,722 megalitres.
Tabulation of data from the image above of the graph
99% |
0 |
90% |
4,209 |
80% |
10,227 |
70% |
19,177 |
60% |
32,827 |
50% |
48,655 |
2022 |
52,514 |
40% |
70,589 |
30% |
89,349 |
20% |
141,190 |
10% |
194,722 |
1% |
372,970 |
Ranked Historic inflow to Lake Eppalock: September - December
Description and Tabulation of the graphical content inflow to Lake Eppalock: September – December
A bar graph titled Ranked historic inflow to Lake Eppalock: September – December is on the page above. X axis label “% Probability of Exceedance” which spans 99% on the left to 1% on the right. Y axis label is “3 month inflow – units megalitres (ML)”. Significant highlighted data in the graph is the difference between the full supply volume of Lake Eppalock and the volume at 1 September 2022 is indicated by the green line: 109,080 ML.
Each % probability of exceedance is reported from 99% to 1%. The general nature of the information presented is low inflow values of less than 10,000 megalitres have a high probability of occurrence. Less than 10% probability of inflows above 95,832 megalitres.
Tabulation of data from the image above of the graph
99% |
0 |
90% |
4,470 |
80% |
12,669 |
70% |
18,286 |
60% |
25,186 |
50% |
37,355 |
40% |
57,050 |
30% |
70,016 |
20% |
99,177 |
Current airspace |
109,080 |
10% |
174,083 |
1% |
345,706 |
Notes for charts:
There are 129 years of historic inflow data available for Lake Eppalock (inflow data for the period before the construction of the dam are based on modeled inflows). The first chart displays the volume of inflow to Lake Eppalock for the period 1 June to 31 August in each of those 128 years. The volumes of inflow shown are ranked in order from lowest to highest with the red line representing the volume of inflow recorded for the period in the current water year (2022).
The second chart displays the volume of inflow to Lake Eppalock for the period 1 September to 31 December in each of the 129 years of historic data. The volumes of inflow shown are ranked in order from lowest to highest. The volume difference at Lake Eppalock between full supply and the storage volume on 1 September is indicated by the green line.
Probability of exceedance: Probability that the volume of inflow will be equal to or greater than a specified volume in any given year.
Additional notes:
- The volumes in spillable water accounts can change due to seasonal determination increases.
- The information provided here for the Campaspe system does not take into consideration the storage sharing arrangements at Lake Eppalock between GMW and Coliban Water.
- Current year inflows are based on operational data.