Barrie Creeks, Lovers Creek, and Hewitt's Creek Subwatershed Plan

The Barrie Creeks, Lovers Creek and Hewitt’s Creek Subwatershed Plan
4.4.3 Climate
The climate of the Barrie Creeks, Lovers Creek, and Hewitt’s Creek subwatersheds directly
determines the quantity of surface and groundwater present in the system. When the spring
melt occurs, a large volume of water is released. This water will first infiltrate the ground. When
the soil becomes supersaturated the remaining water will flow overland until it reaches the
tributaries and main branch of the river.
The temperature in the subwatershed can directly affect the quantity of water present in the
system. In the cold winter months the water is frozen at the surface so the quantity of available
water is reduced. In the hot summer months the water is flowing but an overall loss is occurring
due to the high rates of evaporation.
4.4.4 Water Budget Stress Assessments
Potential water quantity stress is being estimated on a subwatershed scale through the Source
Protection Planning process. Several water budget initiatives have been undertaken to identify
potential water quantity stress within the subwatershed. The indicators of stress presented in
this report are based on these studies and more information can be obtained from the following
reports; SGBLS (2009), AquaResources and Golder (2010), and AquaResources et al. (2010).
Tier 1 Water Budget Results
The Tier 1 Water Budget Study (LSRCA, 2009) conducted a comparison of current conditions
and future demand, on both an average annual and monthly basis. The completion of the
analysis helps to determine whether stress on the groundwater and surface water resources
can be anticipated under various scenarios. The stress assessment evaluates the ratio of the
consumptive demand for permitted and non-permitted users to water supplies, minus water
reserves, within each subwatershed (equation shown in following blue text box). The major
components of the water budget have been estimated and tabulated as described in the
preceding sections, including water supply, water demand, and water reserve.
Results of the current and future groundwater stress assessment using annual average demand
are shown in Table 4-17 and Table 4-18. Both Hewitt’s and Lovers Creeks were found not to be
stressed with regard to average annual stress for current demand, while Barrie Creeks was
found to have a significant potential for stress. For future demand Hewitt’s Creek subwatershed
was found to have a moderate potential for stress, while Barrie Creeks maintained the
significant potential for stress.
Results of the current monthly surface and groundwater stress assessments are shown in Table
4-19. Only Barrie Creeks were found to have a potential for stress with regard to groundwater
on a monthly basis. The lack of seasonal changes in stress levels are a result of a fairly
consistent groundwater supply and consistent municipal pumping for water supply, which makes
up the majority of water demand.
Overall, the results provide a reasonable assessment of the annual groundwater and monthly
surface and groundwater supply and demand conditions. As a result of the current and future
average annual stress assessment the Barrie Creeks, Lovers Creek, and Hewitt’s Creek
subwatersheds advanced to a Tier 2 assessment per the Clean Water Act Technical Rules. The
following sections will discuss the results of the Barrie Creeks, Lovers Creek, and Hewitt’s
Creek Tier 2 Water Budget.
Chapter 4: Water Quantity – Surface and Groundwater 193