Loading...
HomeMy WebLinkAboutStaff Report 4.A 05/02/2016DATE: May 2, 2016 TO: Agenda Item #4.A Honorable Mayor and Members of the City Council through City Manager Dan St. John, F.ASCE — Director, Public Works and Utilities Leah G. Walker, P.E. — Environmental Services Manager SUBJECT: Resolution Approving Award of Bid to Hockney Underwater Weed Cutters / Truxor USA for One Aquatic Plant Harvester in the Amount of $115,158, and Authorizing the City Manager to Execute all Documents Necessary to Complete the Purchase RECOMMENDATION It is recommended that the City Council adopt the attached Resolution approving award of bid to Hockney Underwater Weed Cutters / Truxor USA for one Aquatic Plant Harvester in the amount of $115,158.00 and authorizing the City Manager to execute all documents necessary to complete the purchase. BACKGROUND The Ellis Creek Water Recycling Facility ( ECWRF) includes 163 acres of oxidation ponds, 19 acres of treatment wetlands and 32 acres of polishing wetlands. The oxidation ponds and wetlands were designed to treat peak wet weather influent flows and provide enhanced secondary treatment of all wastewater. To achieve this level of treatment the wetlands were designed with deep open water zones adjacent to shallow zones densely vegetated with California Bulrush. The feasibility report for construction, maintenance, and operation of the wetlands identified the need for a vegetation management program, and the environmental impact report for the ECWRF includes mitigation measures requiring a mosquito control program. To protect public health, the Marin/Sonoma Mosquito and Vector Control District (MSMVCD) established criteria for mosquito prevention in wastewater treatment projects, and the City's mosquito abatement program includes the following elements performed by MSMVCD: surveillance, physical control, biological control, and chemical control. MSMVCD traps mosquitos weekly to identify species, determine population density, and to test for the presence of diseases. Twice in the last two years, mosquitos from trapping events have tested positive for West Nile virus. The City pays MSMVCD for the aerial spraying, fogging, and surveillance; since 2010, the City has paid $405,000 for these activities. MSMVCD has recommended implementing a more aggressive vegetation control program to improve the effectiveness and reduce the costs of their abatement efforts. Vegetation management is necessary to control mosquitos as well as to ensure the wetlands can achieve enhanced secondary effluent water quality standards. The decomposition of excess vegetation creates low dissolved oxygen levels in the wetlands, and the dense vegetation has produced short- circuiting of flow through the wetlands, resulting in a seasonal fluctuation in water quality. Implementing a comprehensive vegetation control program will reduce habitat for mosquitos, improve the effectiveness of mosquito abatement activities performed by MSMVCD, and improve the treatment efficiency of the wetlands. In 2014, Wetlands Solutions, Inc. performed a wetlands process audit, and recommended the City implement a comprehensive vegetation management plan. DISCUSSION The Public Works and Utilities Department evaluated different methods for managing vegetation in the wetlands including manual vegetation control, mechanical vegetation control, chemical vegetation control, and prescribed burning. Multiple contractors specializing in aquatic vegetation removal were solicited to provide proposals and several trends emerged. It was determined manual removal is not practical for such a large area as it would be prohibitively expensive. Chemical control would require the use of systemic or contact herbicides and would still require removal of dead plant material after chemical applications. Prescribed burning has been an effective wetlands management strategy in certain locations, but would require the wetlands to be taken out of service for months to dry the vegetation. In addition, proximity to the location of the adjacent medical facility and a business park make the use of prescribed burns more challenging. Mechanical vegetation control is an efficient viable long -term strategy with minimal impacts to the surrounding environment; however, it does require specialized equipment and skilled labor to work in the wetlands. In 2015, a contractor spent several weeks using a boat -based aquatic harvester to remove vegetation from oxidation Pond 10. While this was effective in returning this pond to open water, the water depths of the vegetative zones in the polishing wetlands at the ECWRF (cells A, B, C, and D) are too shallow to allow for boat -based aquatic vegetation harvesters. However, an amphibious aquatic harvester can operate well in both the shallow wetland cells and in the deep - water zones of the oxidation ponds, where it is capable of collecting aquatic plants. The amphibious harvester can be configured with multiple types of cutters and rakes, providing versatility to operate effectively throughout the wetlands and oxidation ponds. It can collect filamentous algal mats that float on the surface of the oxidation ponds and coon -tail, an aquatic plant that affects the entire water column of the deep -water wetland zones. It cuts and thins bulrush. Purchase of an amphibious harvester will allow staff to perform routine maintenance vegetation removal on a regular basis, and facilitate compliance with the vegetation management strategy and mosquito abatement program. Staff expects the harvester will be used three to four months each year, depending upon weather, site conditions, vegetation regrowth rates, and other factors. Staff has not been able to identify a vendor or contractor for rental of an amphibious harvester. 1A The use of an aquatic harvester is expected to reduce expenditures for mosquito abatement activities and reduce reliance on contractors for vegetation removal. The City pays an average of $82,000 per year for mosquito control and eradication. In addition, the City has paid landscape contractors $81,000 since 2013 to remove bulrush around the perimeter levees of the polishing wetlands, yet such efforts have achieved minimal effectiveness. The Public Works and Utilities Department developed specifications for an amphibious aquatic harvester; the new amphibious aquatic plant harvester will be a model currently in production, and equipped with reed cutting and collecting attachments. An Invitation to Bid (ITB) was issued on February 25, 2016, and three bids for the equipment were received as follows: Name of Bidder Business Location Total Bid Lake Weeder's Digest Minneapolis, MN $93,544.00 Hockney Underwater Weed Cutters / Truxor USA Delavan, WI $115,158.00 McNabb Construction Inc. Lafayette, CA $150,954.93 The apparent low bidder, Lake Weeder's Digest, was found to be non - responsive in the bid proposal. Lake Weeder's Digest proposed equipment that did not meet the minimum equipment specification as outlined in the invitation to bid. The following were exceptions to the Bid specifications in their proposal: • The instrument panel did not include a fuel gauge. • The equipment features a split hydraulic system with one pump for driving the equipment and another pump for powering the tool attachments. • The trailer does not have an assist mechanism to facilitate the raising and lowering of ramp. • A flail mulcher attachment is not available • A cutter /collector attachment is not available A letter of non - responsiveness was issued to Lake Weeder's Digest on April 21, 2016, which was sent via registered mail. The lowest bid that met the minimum specifications as outlined in the ITB was submitted by Hockney Underwater Weed Cutters / Truxor USA; therefore, staff recommends the award of a contract to purchase equipment to Hockney Underwater Weed Cutters / Truxor USA. Hockney Underwater Weed Cutters / Truxor USA has been importing the Truxor line of amphibious equipment made in Sweden since 1996; whereas, Lake Weeder's Digest began importing an amphibious aquatic weed harvester made in the Netherlands in 2015. FINANCIAL IMPACTS The purchase price of the amphibious aquatic plant harvester is $115,158.00. Appropriations in the amount of $90,000 were approved in the mid -year budget to assure availability of sufficient funds in the Wastewater cost center 6600.66700.622 10 for this purchase. ATTACHMENTS Resolution 4 Attachment 1 RESOLUTION APPROVING AWARD OF BID TO HOCKNEY UNDERWATER WEED CUTTERS / TRUXOR USA OF DELAVAN, WISCONSIN FOR ONE AMPHIBIOUS AQUATIC PLANT HARVESTER IN THE AMOUNT OF $115,158.00 AND AUTHORIZING THE CITY MANAGER TO EXECUTE ALL DOCUMENTS NECESSARY TO COMPLETE THE PURCHASE. WHEREAS, the City of Petaluma seeks to purchase one amphibious aquatic plant harvester to manage and maintain vegetation in the Ellis Creek Water Recycling Plant's wetlands and oxidation ponds for the Public Works and Utilities Department; and WHEREAS, the City conducted a competitive bidding process for the amphibious aquatic plant harvester in compliance with Petaluma Municipal Code section 4.04.080 by preparing and distributing an Invitation to Bid to furnish one amphibious aquatic plant harvester; and WHEREAS, an Invitation to Bid was issued on February 25, 2016, and three bids were received and opened on March 23, 2016, in accordance with applicable law; and WHEREAS, Lake Weeder's Digest of Minneapolis, MN, was the apparent lowest bidder; and WHEREAS, Notice was provided that Lake Weeder's Digest's bid was non - responsive because the proposed equipment failed to meet specifications; and WHEREAS, the lowest responsible bidder for the equipment was submitted by Hockney Underwater Weed Cutters / Truxor USA for $115,158.00; and WHEREAS, the Public Works & Utilities Department will utilize budgeted funds from fiscal year 2015/2016 to purchase the equipment. NOW, THEREFORE, BE IT RESOLVED that the City Council of the City of Petaluma approves the purchase of one amphibious aquatic plant in the amount of $115,158.00 from Hockney Underwater Weed Cutters / Truxor USA of Delavan, WI, and authorizes the City Manager to execute all necessary documents to complete the purchase.