7. CONSIDER AUTHORIZATION OF FUNDS TO RENT IRRIGATION EQUIPMENT FOR THE SAN CARLOS IRRIGATION SYSTEM
Meeting Date: July 19, 2004 Budgeted: Yes
Program/Line Item No.: 2-1-1-A
General Counsel Approval: N/A
Committee Recommendation: The Administrative Committee reviewed this item on July 12, 2004 and requested additional information. The additional information has been included in the staff note.
SUMMARY: The District has irrigated riparian vegetation in the vicinity of Cal-Am’s San Carlos Well since 1988 (except for the 1995 and 1998 El Niño years) to offset the impacts associated with ground water pumping. Over the years, several irrigation techniques including drip irrigation have been used. However, for this particular site, a temporary sprinkler irrigation system has been found to be the most successful method. This system can be rented at relatively low cost and requires little to no maintenance except for initial set up in summer and removal during the winter season.
RECOMMENDATION: Authorize the General Manager to rent irrigation equipment from Rain for Rent at a cost not to exceed $2,500. If approved, this item will be adopted along with the Consent Calendar. The Administrative Committee reviewed this item on July 12, 2004 and requested additional information. The additional information is included in the staff note.
IMPACTS ON STAFF AND RESOURCES: The Fiscal Year 2004-2005 budget includes funds to rent irrigation equipment for the San Carlos Irrigation System. Funds are budgeted under Program 2-1-1-A, Riparian Habitat Mitigations, Irrigation Program, “Operate and maintain 4-well system” (Account No. 4-7850.11, $5,000). A portion of the funds for this budget item are reimbursed by Cal-Am every year as a contribution to the maintenance and operation of irrigation systems for riparian vegetation in the area of Cal-Am’s four Lower Carmel Valley wells (Cañada, San Carlos, Cypress, and Pearce). Water is supplied by Cal-Am at no cost to the District for irrigation in the four-well area. Costs for rental of the irrigation equipment will not exceed $2,500. This work will be performed under the direction of the District’s Riparian Projects Coordinator.
BACKGROUND: The District operates nine irrigation systems in Carmel Valley to mitigate for surface and ground water diversions during the dry season. The riparian corridor has responded favorably with additional growth and diversity, contributing to channel stability and enhancing riparian habitat.
For the San Carlos site, sprinkler irrigation has been found to be the most successful method. Portable aluminum laterals with impact sprinkler heads on four-foot risers are placed along the toe of the bank, and the risers allow irrigation of the banks. This method is used in place of drip irrigation because the vegetation in this area has become very dense, and replacing clogged emitters and performing annual maintenance of a drip system has become too hazardous and difficult. The water use for the San Carlos area has averaged approximately three acre-feet per year.
During 1999, 2000, 2001, and 2002, the District used the sprinkler method, renting equipment from Rain for Rent. In 2003, the equipment was not rented and used because there was adequate ground water in this reach, evidenced by standing pools of water throughout the irrigation season. The river in this area dried up in Mid-June 2003, and ground water levels will continue to decline until the next season’s rains result in renewed river flow. During dry periods, it is critical to irrigate riparian vegetation to maintain its health and vigor. If the San Carlos area were not irrigated this year, the vegetation could die, leading to loss of prime riparian habitat and bank instability.
District staff has investigated purchasing the equipment as an alternative to renting. The cost to purchase the equipment is about $10,000. In addition to the high capital cost, if the District were to own the equipment, it would need to be stored for much of the year, when the river is flowing. There is not adequate space at Cal-Am’s San Carlos Well nearby, and space is not available at storage sites the District is now renting. For these reasons, the District has found renting the equipment to be the best option. Rain for Rent was chosen because of their location and price in comparison with other irrigation equipment suppliers. The business office is in South Salinas, and they have equipment storage sites throughout the county. The other primary source for District irrigation equipment and supplies, Martin’s Irrigation Supply, has an office in Sand City, but they do not carry the type of equipment needed for the San Carlos Irrigation System. The District has used Rain for Rent for four years, and the service and equipment have been excellent.