182 
Ganl. Bull. Singapore 70 (Suppl. 1) 2018 
Table 2. Scenarios for future eco-hydrology management. 
Reservoir 
Level 
No. 
Rainfall 
Low Medium 
High 
Low 
1 
2 
4 
4 
Medium 
5 
6 
7 
8 
High 
9 
10 
11 
12 
Table 3. Proposed drought mitigation management strategies for Scenario 9. 
Drought 
Mitigation 
Management 
Strategies 
Location 
and 
Symbols 
Discharge 
rate at each 
point source 
(m3/s) 
Volume at 
each point 
source 
(m3/day) 
Total 
Discharge 
Volume (m3/ 
day) 
Proposed 
System 
9A 
®in Fig. 7 
0.02 
1,728 
26,000 
Pump + Pipe 
9B 
®in Fig. 7 
0.04 
3,456 
52,000 
Pump + Pipe 
9C 
Ain Fig. 7 
0.02 
1,728 
26,000 
Pipe 
9D 
Ain Fig. 7 
0.01 
864 
13,000 
Pipe 
Scenario 1 would have been the obvious severe drought case to be studied and 
a series of drought mitigation managements would be recommended accordingly. 
However, we consider Scenario 9 more appropriate in the Singapore context, as 
Singapore is unique in its number of desalination plants and recycled water plants. 
During the unusually long dry periods in early 2014 and 2015, many of the desalination 
and recycled water plants were operating at their full capacity. With this in mind, in 
this study the focus is placed on Scenario 9 as the severe drought scenario. Scenario 
12 is selected as the severe flood case; it is analysed and a series of flood mitigation 
management strategies is proposed. 
Management strategies 
Severe drought case 
Based on the climate projections for Singapore, the unprecedented five consecutive 
severe drought years that occurred in California (Reid, 2015), and the severe droughts 
experienced in other places such as North Korea, Brazil and South Africa, Scenario 
9 is selected for the severe drought case study; the drought mitigation management 
strategies for the Nee Soon freshwater swamp forest are then proposed. Table 3 
summarises the proposed drought mitigation management strategies to tackle the dry 
situation in Scenario 9. Point sources at strategically selected locations, as shown in 
