2012-10-04_HYDROLOGY - M2002020

• Permit No: M2002020
• IBM Index Class Name: HYDROLOGY
• Doc Date: 10/4/2012
• Doc Name: Amended SWSP
• From: OSE
• To: Martin and Wood Water Consultants, Inc
• Permit Index Doc Type: Hydrology Report
• Email Name: PSH
• Media Type: D
• Archive: No

Ms. Michelle Johnson
25 Ave SWSP Amendment
October 3, 2012
Page 2
depletion analysis. Once the pit refills with groundwater in the future, additional depletions will
result, and the applicant will replace depletions from this "first fill" above and beyond the
depletions from the maintenance pumping. The first fill is projected to consist of 443 AF which
will begin filling in November 2012.
All surface water within Pit 5 has been classified as pre -81, and thus exempt from
evaporative losses (see previous SWSP). Therefore the reduction in water surface area of Pit 5
will not reduce the evaporative depletions that are to be replaced under this SWSP.
Dewatering Pit 5 will create additional depletions of 345.57 AF (August 2012 through
November 2012) due to dewatering, and 443 AF due to the refilling Pit 5. As these depletions
do not hit the river instantaneously, the Applicant lagged these depletions using the IDS AWAS
program with the following parameters:
• X, distance from the well to the stream = 1,733 feet
• W, width of the alluvial aquifer = 11,503 feet
• T, Transmissivity = 164,132 gallons per day per foot
• S, Specific Yield = 0.20
The maximum lagged water loss due to Pit 5 dewatering activities are 442.56 acre -feet
for August through December 2012, 247.17 acre -feet for 2013, and 26.20 acre -feet for January
through May 2014. See Table 1B for the monthly breakdown of all depletions associated with
this SWSP Amendment.
Replacement
As the City of Greeley is the operator and owner of the site, Greeley is responsible for
covering all depletions under this SWSP. For this SWSP amendment, Greeley will use
replacement water that is already a part of this SWSP; namely, reusable effluent out of their
waste water treatment plant (WDID 0302312) during the non - irrigation season, and credits from
their shares of the Boyd & Freeman Ditch during the irrigation season. Greeley's projected
replacement amounts are shown on Table 1 B, however, Greeley reserves the right to use any
other legally available water source that is already a part of this SWSP including water stored in
Flatiron Pits 1 and 2 (aka Poudre Ponds) pursuant to its storage rights in Case No. 99CW234.
Additionally dewatering credits from the dewatering operation of Flatiron Pits 3 & 4 are used to
offset the amount of replacement water needed. In total, the required amounts of replacement
water are as follows: 229.80 acre -feet from November — December 2012, 173.99 acre -feet in
2013, and 12.34 acre -feet from January through May 2014.
SWSP Conditions of Approval
I hereby approve the amended substitute water supply plan in accordance with §37 -90-
137(11), C.R.S. All terms and conditions of the original SWSP remain in full force and effect.
For convenience, the original SWSP terms and conditions are provided below:
1. This plan is approved with the effective date of June 1, 2012 and shall be valid through
May 31, 2014 unless otherwise revoked or modified. If this plan will not be made absolute
by a water court action by the plan's expiration date, a renewal request must be submitted
to this office with the statutory fee of $257 no later than April 15, 2014.
2. Well permits no. 58476 -F and 59809 -F were previously obtained for these pits but will no
longer be valid with the implementation of this SWSP. A new well permit application has
been submitted to this office and is pending on approval of this plan. The provisions of