C150379 Feasibility Study

• Contract/PO #: C150379
• Contractor Name: Wadley Farms Filing No. 3 Homeowner's Association
• Contract Type: Loan
• Water District: 7
• County: Adams
• Loan Projects - Doc Type: Feasibility Study

average would have a 10% chance of occurring in any single year and would only yield
78 acre -feet. This is barely enough to cover evaporation from the Wadley Reservoirs if
irrigation use is severely restricted, such as for tree watering only, and is likely
insufficient to maintain fire - fighting reserves if carryover storage from the previous year
is minimal. Therefore, the HOA currently faces the risk of having insufficient water
supplies in six out of ten years and has a 10% chance of having insufficient fire- fighting
reserves and highly- restricted irrigation water each year or in one year in ten on average.
The HOA attempts to maintain as much carryover storage as possible from one year to
the next in order to protect against shortages in annual water deliveries. However, if
slightly below average to dry years come back to back, without intervening wet years to
replenish carryover storage, there is insufficient reservoir storage water available to
carryover for offsetting any large reduction in water deliveries in the second or
subsequent years of a dry period.
Table 7: Percentile Occurrence Frequency for Current Water Supplies
% of years with water
availability less than amount
shown
acre -feet of water available
from FHL shares at Wadley
Farms No. 3 head ate
1 %
56
10%
78
20%
105
30%
110
40%
117
50%
122
60%
132
70%
141
80%
158
90%
172
Alternatives for Increasing Water Supul-
The HOA has reviewed numerous alternatives for increasing the amount and reliability of
its water supplies over the past two decades. Some of these alternatives have already been
implemented. The HOA has increased the capacity of its reservoirs, rehabilitated the
dams to remove storage restrictions, applied seepage control products to the feeder
ditches and reservoirs, rebuilt the headgate from the Signal Ditch to access low flows,
installed meters at each individual lot, and implemented a system for restricting
homeowner water use during shortages. Other alternatives were explored, such as are
documented in the Bishop - Brogden report, and some are discussed below.
No .fiction Alternative
If no action is taken, the water supply for Wadley Farms No. 3 will decrease in the future.
The HOA has been able to lease up to 1.0 FHL share over the past decade in addition to
the three FHL shares owned by the HOA. However. the owner of 0.125 of these shares
Wadley Farms No. 3 Water Supply CWCB Loan Feasibility Study Page 21