2021-02-24_HYDROLOGY - M1997054

• Permit No: M1997054
• IBM Index Class Name: Hydrology
• Doc Date: 2/24/2021
• Doc Name: Substitute Water Supply Plan
• From: DWR
• To: DRMS
• Email Name: TC1
• Media Type: D
• Archive: No

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State Engineer's General Guidelines for Substitute Supply Plans for Sand and Gravel Pits,
subtracting the pro-rata amount of the effective precipitation for that period.
You have provided a monthly breakdown of the depletions under this SWSP on the attached Table 2,
which includes 15.53 acre-feet of net evaporative loss, 8.86 acre-feet of water lost in product
(based on an estimated 600,000 tons of washed aggregate and 150,000 tons of unwashed
aggregate), and 24.0 acre-feet for on-site dust control, for a total consumptive use of 48.38
acre-feet.
The IDS Alluvial Water Accounting System ("AWAS") stream depletion model was used to determine
the lagged depletions from dewatering, evaporation and operational losses to the Arkansas River.
The aquifer characteristics used in the model are: transmissivity (T) = 55,000 gallons per day per
foot and specific yield (SY) = 0.2, the distance of the exposed ground water to the stream = 1,400
feet (measured from the centroid of the exposed ground water surface), and the location of the
parallel impermeable boundary was estimated to be 2,650 feet from the stream.
During this plan approval period, no groundwater will be used for reclamation, concrete batching,
or any other purpose not described above. As shown on Table 3, attached, the total consumptive
use was calculated to be 48.39 acre-feet and lagged stream depletions were calculated to total
48.84 acre-feet during this SWSP period.
SITE DEWATERING
The Applicant began dewatering the Parkdale Pit in 2012 to assist in the mining of material below
the groundwater table. The water is removed from the ground and placed into a series of
dewatering trenches. This water will be eventually piped and then discharged on the north side of
the property boundary into Currant Creek which is a tributary to the Arkansas River. All water
pumped from the pit reaches the Arkansas River within the same month it is pumped. The Applicant
will monitor the dewatering operations and include the data in their monthly accounting submittals
to the State Engineer's Office.
REPLACEMENTS
The proposed sources of replacement water for this pit include a five-year lease of 50 acre-feet per
year of fully consumable water from the Board of Water Works of Pueblo ("PBWW"), valid April 1,
2016 through March 31, 2021 (attached), and the applicant's ownership of 5 shares of Twin Lakes
Reservoir and Canal Company stock, which are estimated to yield approximately 3.5 acre-feet/year
of water. The PBWW water will be provided at the City of Pueblo wastewater treatment plant
located east of Pueblo when adequate exchange potential exists to make that replacement water
available at the Parkdale Project site. When there is insufficient exchange potential to utilize
reusable effluent, the PBWW will release water from upstream storage at Twin Lakes Reservoir.
Upstream reservoir releases will be subject to a 0.07 percent per mile river transit loss, which
equates to approximately 6.55 percent from Twin Lakes to Parkdale. The Applicant is in the process
of acquiring an extended lease with PBWW.
Martin Marietta Materials has an additional backup supply for this project from a 50 acre-foot lease
with Canon City Water Department, which will only be used in the event that the other sources