Cultural Water Demand in the Coconino Plateau Basin

Cultural Water Demands

• Refer to Table 6.1-8 and Figure 6.1-11.

• Population in this basin increased from 6,977 in 1980 to 9,164 in 2000 and is projected to reach 17,500 by 2030.  This is the most populous basin in the planning area.

• All cultural water use in this basin is for municipal demand.  Municipal demand centers include Williams, Tusayan, Grand Canyon Village, Valle, Supai and Cameron.

• Groundwater demand is small and has remained relatively constant from 1971-2005.  In 2000 the City of Williams started using groundwater because surface water supplies were unavailable due to drought. Groundwater use in Williams increased to 389 acre-feet in 2006.

• Data on municipal surface water use prior to 1991 is not available.  From 1991-2005 municipal surface water use decreased from 500 acre-feet per year (AFA) to 300 AFA due to surface water shortages in Williams.     

• As of 2005 there were 172 registered wells with a pumping capacity of less than or equal to 35 gallons per minute and 38 wells with a pumping capacity of more than 35 gallons per minute.

Effluent Generation

• Refer to Table 6.1-9.

• There are eight wastewater treatment facilities in this basin.

• Information on population served was available for two facilities and information on effluent generation was available for five facilities.  These facilities serve over 4,200 people and generate over 1,700 acre-feet of effluent per year.

• Four facilities discharge to watercourses, one discharges to an evaporation pond, one discharges for irrigation, four discharge to golf course or landscape irrigation, two discharge for municipal uses such as toilet flushing and two discharge to an unlined impoundments that recharge the aquifer.

Click for Table 6.1-9 Effluent Generation in the Coconino Plateau Basin

Click for Figure 6.1-11 Coconino Plateau Basin Cultural Water Demand