Memorandum
City of Lawrence
Engineering
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TO: |
David L. Corliss, Diane Stoddard, Cynthia Wagner |
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FROM: |
Chuck Soules |
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Date: |
January 12, 2010 |
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CC: |
Jonathan Douglass, Mark Thiel, Steve Bennett, Roger Zalneraitis , Dave Wagner, Philip Ciesielski Michael Almon, Ted Boyle, Roger Pine, Lane Williams, Dean Elliott Craig Weinaug, Keith Browning, Douglas County Commission, Grant Township |
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RE: |
Lawrence Municipal Airport – Sanitary Sewer Agenda Item for January 19, 2010 City Commission |
Please include the following item on the City Commission’s January 19, 2010 agenda.
Project Background. The airport is located north of US Route 24/40 about one-half mile east of 3rd Street. It is a valuable asset to the City, currently accommodating over 32,000 operations annually and generating over $9 million dollars in local revenue for the economy. The airport is approximately 500 acres, has two runways, a terminal, 36 t-hangars, and several small on-site aviation services and hangars used by local businesses and individuals. The airport is an “island” of City property, located about a mile north of the City border.
While the airport provides a valuable service to the community, it is currently underutilized due in part to inadequate City infrastructure. The airport is served by an 8 inch waterline for basic office use, but is insufficient for fire suppression. Wells have to be drilled for fire safety, and there may be a limit to the number of wells that can be drilled. Airport facilities have no sewer services, using septic instead. County regulations prohibit more than one septic and lateral field every three acres. This requires land that could otherwise be used for development to remain as open space for septic.
There is an immediate need for additional sewer facilities at the airport. At least one septic system is failing, and some recent firm inquiries would require greater service capacity by late spring of 2010. Also, a number of business inquiries have occurred over the last year for locations at the airport that suggest that the airport has more demand for business space than can be accommodated by existing water and sewer service.
AIRPORT WATER MAIN
Project Description. Installation of a 12” water main to Lawrence Municipal Airport. Waterline will extend north on N. 7th Street (E 1500 Road), then east on HWY 24 to Airport Road, and north to the terminal. The new waterline will be looped with current service at the airport, and will provide sufficient flows to meet fire needs and provide usage for new businesses to develop at the airport.
Project Status. On May 26, 2009 the City Commission authorized BG Consultants to prepare plans. The project bid was awarded to R. D. Johnson on October 15, 2009. Installation of both 12 inch and 8 inch ductile iron pipe is currently underway. Water line has been installed from North Street to approximately 100 feet south of the KTA crossing along the west side of 1500 Road, from
the terminal building to 24/40 along the west side of Airport Road, and from Airport Road to approximately 300 feet east of 1500 Road along the north side of 24/40. Crews assigned to the project have made significant progress and the project is approximately 50% complete. Construction is required to be completed by March 15, 2010 per the project contract.
AIRPORT SANITARY SEWER
Project Description. As directed by the City Commission, BG Consultants and Burns & McDonnell Engineering prepared a report on providing sanitary sewer options, including alternative treatment options. The study looked at:
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§ Lift Station and force main |
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§ Septic holding well and hauling |
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§ Constructed wetlands/green machine |
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§ Packaged treatment system |
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§ Tree farm |
The options were evaluated based on the following parameters (Table 5 of Report)
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§ Ability to handle projected wastewater characteristics |
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§ Ability to operate without interference with airport operations |
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§ Expandability |
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§ Permitting |
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§ Operation |
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§ Applicability for short/long term use |
Costs were also developed in Appendix D and summarized in Table 10 of the report.
BG Consultants reviewed an on-site gravity system to connect existing and future facilities to a treatment option (report attached). The report recommends a phased approach. Initially a septage holding well/wet well would be installed to collect the wastewater from the on-site airport gravity collection system. The wastewater would be collected and hauled to the Wastewater Plant on an “as-needed” basis until such time as flows would warrant the lift station to be installed. The septage holding well would then be converted into a lift station by adding pumps and controls. Because construction costs have been favorable, it is recommended that the City proceed with the installation of the force main. The force main would remain unused until the lift station was operational. Consequently, the City would be better prepared (within 60-90 days versus 9-12 months) when approached by a development/business.
Project Status.
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May 26, 2009 – BG Consultants and Burns & McDonnell hired to prepare a study |
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November 16, 2009 – Draft sewer report presented to Airport Advisory Board. Recommendation that the City Commission proceed with the airport collection system and holding tank/wet well and force main installation |
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December 21, 2009 – Public meeting to present study |
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January 19, 2010 - Study presented to City Commission |
Recommendation. Based on the study and Aviation Advisory Board recommendation, staff requests that the City Commission authorize the City to negotiate an engineering contract with BG Consultants for plans and specifications for the construction of:
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§ Phase 1 of the Airport collection system estimated construction cost of $420,000 |
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§ Septic holding well estimated construction cost of $331,000 |
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§ Lift station and force main estimated construction cost of $1,220 million |
At this time the lift station would not include pumps and controls as there would not be enough wastewater produced. The City will pump and haul the wastewater as needed from the lift station wet well (also called septage holding well). The estimates are preliminary and construction prices have been favorable recently.
Please let me know if there are any questions.
Respectfully submitted,
Charles F. Soules, P.E.
Director of Public Works
CFS/je
Attachments: BG Consultants Collection System Report