Arkansas - Las Animas Sanitary Sewer System Improvements_Application

• Basin Roundtable: Arkansas
• Applicant: City of Las Animas
• Description: City of Las Animas Sanitary Sewer System Improvements
• Account Source: Statewide
• Board Meeting Date: 3/19/2008
• WSRA - Doc Type: Grant Application

Water Supply Reserve Account - Grant Application Form
Fonn Revised May 2007

EXISTING GROUND WATER WELLS

Pumping Absol ute
Well Permit No. Structure Depth, Rate Right, Appropriation Actual Street
No. No. tt. gpm1) Pumping Date Location
Limit gpm
1 15297-R 5069 28 340 850 1919 6th & Cottonwood
22) 431-RF 6208 29 250 550 June 25, 1967 4t & Cottonwood
3)
3 15299-R 5067 26 367 900 1948 1st & Elm
4 5469-F 5070 34 350 675 April 30, 1967 3ra & Vine :5)
5 432-RF 5071 30 350 675 Julv 20 1967 2na & Locust :5)
6 15296-R 5072 33 400 1450 1906 8th & Ash
7 5350-F 5068 36 520 1150 March 31,1964 Ash south ot 11tn
3)
8 2452-F 6207 - 04) 150 June 30, 1960 4th & McBride :5)
- 21690-F 5839 - - 245 1928
- 29691-F 5840 - - 260 1928
- 29692-F 5873 - - 18 1920

1. gpm = Gallons per minute
2. Currently being replaced
3. State Engineer database record of location is not consistent with current location
4. Abandoned
5. Located in SW % of NW % Section 11

Only Well Nos. 1 through 7 are active. Well NO.8 has been abandoned; however, this well is to be redrilled
within the proposed water project ongoing concurrently. The three wells without well numbers are not used
for the city's water supply.

As a result of the proposed improvements, the city is anticipating two results in regard to state waters. As a
result of the existing condition of the sewage collection system, two things are occurring. They include the
collection system acting like a french drain in those areas ground water is higher than the piping and as a
recharge pipe in those areas where ground water is lower than the pipe. These conditions are brought about
by the cracks and missing segments of the old VCP piping.

These two phenomenon have impacts to both the available amount of water and water quality. Based on the
PER, during the summer months the WWTP sees an upswing of inflow of approximately 56,500 gallons per
day, which represents roughly 11 % of the total volume of the city's wastewater treatment system. Based on
an average annual evaporation rate of 51-inches per year, an annual precipitation rate of 12.3-inches per
year and a total water surface area of the WWTP of 250,000 square feet, the WWTP's evaporation loss is
approximately 18.5 acre-feet (ac-ft). As a result of the infiltration representing 11 % of the WWTP's total
volume, this represents a little over 2 ac-ft of non-consumptive water loss per year. This calculation does not
take into account that the conversion of the ground water to surface water will result in additional evaporative
losses subsequent to the surface water discharge from the wastewater treatment plant. Water discharged
from the plant is conveyed through a ditch to the Arkansas River and remains in the form of surface water
thereby being subjected to yet additional evaporative losses. By eliminating the infiltration into the sewer
system, this represents a net gain of water within the Arkansas River Basin of a minimum of 2 ac-ft per year.
This essentially frees up water for other users within the basin and thereby reduces the overall water gap
within the basin. With regard to the ground water quality, exfiltration of raw wastewater from the collection
system into the ground water has a negative impact on water quality. Raw sewage represents significant
health concerns and has an overall degradation of water quality. Furthermore, the Colorado Department of
Public Health and Environment closely regulates and strictly forbids discharges of raw sewage. By
eliminating raw sewage exfiltration, water quality within the vicinity of Las Animas is anticipated to improve. In
order to eliminate these net negative affects, the city is focused on sewer main replacement.

F:\WPDATA\Las Animas\Wastwater\06 SSCoI\Financial\Roundtable\06-07 Application (may 07).doc

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