Meeting Date:

June 18, 2007


Included in Proposed FY 2007-2008 Budget



David A. Berger,




General Manager

Line Item No.:


Prepared By:

Thomas Christensen

Cost Estimate:



General Counsel Approval:  N/A

Committee Recommendation:  The Administrative Committee reviewed this item on June 7, 2007 and recommended approval.

CEQA Compliance:  N/A


SUMMARY: The District has irrigated riparian vegetation in the vicinity of California American Water’s (CAW) San Carlos and Cañada Wells since 1988 (except for the 1995 and 1998 El Niño years and the relatively wet years of 2003, 2005, and 2006) to mitigate the effects of groundwater pumping. Over the years, several irrigation techniques including drip irrigation have been used.  However, for this particular site, a temporary overhead sprinkler irrigation system has been found to be the most successful method.  This system can be rented at relatively low cost, is simple to set up and remove, and requires minimal maintenance to operate.  Because this is a critically dry year along the Carmel River, staff anticipates that a second system may need to be installed to irrigate streambanks in the vicinity of the Pearce Well, which is located about one mile downstream of the Schulte Road Bridge.


RECOMMENDATION:  Authorize the General Manager to rent irrigation equipment from Rain for Rent at a cost not to exceed $7,000.  If approved, this item will be adopted along with the Consent Calendar. 


IMPACTS ON STAFF AND RESOURCES:  The proposed Fiscal Year 2007-2008 budget includes funds to operate and maintain irrigation equipment for the protecting riparian vegetation in the area of four Lower Carmel Valley wells owned by CAW.  Funds are proposed under Program 2-1-1-A, Riparian Mitigations, Irrigation Program, “Operate and maintain 4-well system” (Account No. 4-03-7850.11, $7,000).  A portion of the funds for this item are reimbursed by CAW every year as a contribution to the maintenance and operation of irrigation systems for riparian vegetation in the area of CAW’s four Lower Carmel Valley wells (Cañada, San Carlos, Cypress, and Pearce).  Water is supplied by CAW at no cost to the District for irrigation in the four-well area.  (This water is included in CAW’s “Non-Revenue Metered Use” category and is not a part of “Unaccounted-for Water.”)  The cost of leasing equipment to irrigate for the area influenced by the San Carlos and Cañada Wells is estimated at approximately $2,550.  It is evident that 2007 is a dry year, with river flows well below the levels during the past several years.  We anticipate that pumping by CAW and others from Lower Carmel Valley will cause the groundwater levels to decline below the root zone of riparian vegetation.  In the event it becomes necessary to install rented irrigation equipment at additional locations, staff is requesting authorization to expend up to $7,000 during the 2007 irrigation season.  Installation and operation of the systems 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 Cañada-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.  A similar system would be put into place in the vicinity of the Pearce Well, if dry conditions persist and riparian vegetation undergoes increased stress due to groundwater pumping.


The District has used the sprinkler method in most years since 1999, renting equipment from Rain for Rent.  Equipment was not rented and used in years where there was adequate groundwater in this reach as evidenced by standing pools of water throughout the irrigation season (e.g., during the 1995 and 1998 El Niño years and in 2003).  However, ground water pumping has increased in the lower Carmel Valley pursuant to direction by the State Water Resources Control Board and a Conservation Agreement between CAW and the National Marine Fisheries Service.  When groundwater levels drop, it is critical to irrigate riparian vegetation to maintain its health and vigor.  If the Cañada-San Carlos Wells 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 equipment for a single system is in excess of $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 CAW’s San Carlos Well site, 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’s experience with Rain for Rent’s service and equipment has been excellent.