COMMISSION 
AGENDA MEMORANDUM                        Item No.          4e 
ACTION ITEM                            Date of Meeting       June 27, 2017 
DATE:     June 20, 2017 
TO:        Dave Soike, Interim Executive Director 
FROM:    Mike Tasker, Director, Aviation Facilities and Infrastructure 
Wayne Grotheer, Director, Aviation Project Management Group 
SUBJECT:  Pond Netting Repair Safety Improvement 
Amount of this request:                            $455,000 
ACTION REQUESTED 
Request Commission authorization for the Executive Director to use Port Construction Services 
to repair damaged stormwater pond nets at Seattle-Tacoma International Airport in 2017 in the
amount of $455,000. 
EXECUTIVE SUMMARY 
This project will repair damaged pond netting at 10 storm water ponds and three industrial
wastewater system (IWS) ponds at the Airport. Pond netting is installed at the Airport's
stormwater detention ponds to deter waterfowl from the airfield in order to reduce aircraft
bird strikes. The nets were damaged during a snow storm in early 2017 and need to be repaired 
before the fall season in the interest of safety. The costs for these repairs were not anticipated
in the 2017 budget. 
The repairs are planned to be accomplished by combination of Port Construction Services selfperformed
work and small works contract. The cost of making the repairs in 2017 is estimated
to be $455,000. The costs will be accounted for as operating costs. 
JUSTIFICATION 
The Port has constructed a series of detention ponds around the Seattle-Tacoma International
Airport to mitigate the impacts of stormwater runoff on nearby streams. These ponds attract 
wildlife,  particularly  waterfowl,  which  are  a  known  aviation  safety  risk.  The  Airport  has
effectively used pond netting to prevent access to the ponds by waterfowl, and in turn reduced
the number of bird strikes by aircraft. There has been an increase in aircraft strikes with
waterfowl since the beginning of the year that might be interpreted as being related to damage
of the pond netting system. 


Template revised September 22, 2016.

COMMISSION AGENDA  Action Item No. _4e___                              Page 2 of 4 
Meeting Date: June 27, 2017 
Federal Aviation Regulations (FAR) Part 139.337 require airports, including Seattle-Tacoma
International Airport, to take immediate measures and mitigate wildlife hazards whenever
hazardous conditions exist. According to FAA Advisory Circular 150/5200-33B, the FAA requires
immediate correction of any hazardous wildlife attractants arising from existing storm water
facilities located on or near airports. Areas of water that remain open in excess of 48 hours
must be mitigated using appropriate waterfowl exclusionary measures such as netting. 
The frequency with which hazardous birds were harassed has increased in 2017. Mitigation
measures, such as launching pyrotechnics, are only acceptable for a short term and cannot be
considered as an alternative to the pond netting repair. Preventing waterfowl access to the
ponds will reduce their presence in the general vicinity of the airport, reduce an operational
need for direct control of wildlife, better protect birds from being struck and injured by aircraft,
and return the Port's efforts back to habitat management which is the primary and the
preferred method for reducing wildlife conflict. 
The pond netting repair will reduce the risk of aircraft strikes with waterfowl. One bird strike
that occurred at the end of April, 2017 resulted in damage to an aircraft that exceeded $1 
million in cost. The damage required the repair of two engines, landing gear and the aircraft
being out of service for at least 5 days. 
The best weather that allows access to the ponds is during the July to October dry season. The
repair to the facilities is anticipated to use quick methods that may be temporary in nature. A
2018 capital project request has been submitted to improve the bird deterrent system for all
stormwater ponds and lagoons.  The project will develop a study that will evaluate current
infrastructure, feasibility, and improvement recommendations.. 
Scope of Work 
Repair the damaged bird netting systems at the 10 storm water ponds and 3 IWS ponds on or
near the airport to reduce the access of birds to the ponds and discourage the presence of
waterfowl in the area. 
Schedule 
Activity 
Design start                                        2017 Quarter 2 
Construction start                                 2017 Quarter 3 
In-use date                                        2017 Quarter 4 
Cost Breakdown                                     This Request           Total Project 
Design                                                           $0                     $0 
Construction                                              $455,000               $455,000 
Total                                                           $455,000                $455,000 

Template revised September 22, 2016.

COMMISSION AGENDA  Action Item No. _4e___                              Page 3 of 4 
Meeting Date: June 27, 2017 
ALTERNATIVES AND IMPLICATIONS CONSIDERED 
Alternative 1  Maintain current conditions: The Port would not repair the damaged netting
systems for storm water ponds or IWS ponds at the airport in the dry season of 2017. 
Cost Implications: $0 
Pros: 
(1)   No additional cost in 2017. 
Cons: 
(1)   The increased habitual use of ponds on or near the airport by waterfowl is well 
documented. Doing nothing would result in an increasing potential risk of bird-aircraft
strikes. 
(2)   Not in compliance with FAR Part 139 requirements or FAA Advisory Circular 150/5200-
33B. 
This is not the recommended alternative. 
Alternative 2  Repair the facilities by quick methods. 
Cost Implications: $455,000 
Pros: 
(1)   Reduce the access of birds to the ponds on or near the airport and the presence of the
water fowl in the area to improve air traffic safety at the airport. 
(2)    Comply with FAR Part 139 requirements or FAA Advisory Circular 150/5200-33B. 
(3)    Utilize the dry season between July and October for the best access to perform work
in the ponds. 
Cons: 
(1)   Capital/Expense spending in 2017 
This is the recommended alternative. 
FINANCIAL IMPLICATIONS 
Cost Estimate/Authorization Summary              Capital        Expense           Total 
COST ESTIMATE 
Original estimate                                          $0        $455,000        $455,000 
AUTHORIZATION 
Previous authorizations                                   $0               $0               $0 
Current request for authorization                         $0        $455,000        $455,000 
Total authorizations, including this request                $0        $455,000        $455,000 

Template revised September 22, 2016.

COMMISSION AGENDA  Action Item No. _4e___                              Page 4 of 4 
Meeting Date: June 27, 2017 
Remaining amount to be authorized                    $0             $0             $0 
Annual Budget Status and Source of Funds 
The repairs for the unexpected damages to the ponds due to the winter storm in amount of
$455,000 will be absorbed within the approved 2017 operating budget, and funded with the
Airport Development Fund. 
Stakeholders have requested a 2018 capital project to address long-term solutions for the bird
deterrent systems. 
Financial Analysis and Summary 
Project cost for analysis              $455,000 
Business Unit (BU)                  Airfield Movement 
Effect on business performance     NOI after depreciation will decrease 
(NOI after depreciation) 
IRR/NPV (if relevant)                N/A 
CPE Impact                       $0.01 
Future Revenues and Expenses (Total cost of ownership) 
It is likely that pond netting will need more frequent repairs or replacement to maintain
functional integrity. 
ATTACHMENTS TO THIS REQUEST 
Presentation slides 

PREVIOUS COMMISSION ACTIONS OR BRIEFINGS 
None. 






Template revised September 22, 2016.