The squirrel bridge design
While the Nutty Narrows Bridge is very beautiful and ornate, many parts of its design are not actually functional and do not help the squirrels. For my bridge, I ultimately chose the simplest rope-only design, as the most functional:
Even with this simple design, actually making it happen was far from easy.
Because the bridge crosses the roadway, I needed to get a right-of-way permit approved by the city.
City council members spoke with me, the mayor spoke with me, the director of public works spoke with me, and the city engineer spoke with me. They told me that in order to put what is essentially a rope across the road between two trees, I would need to apply for a right-of-way (ROW) permit. While they seemed somewhat supportive, the requirements for the permit only kept piling up.
I needed to get approval from neighboring property owners. I had to submit design documents and a traffic management plan for the construction period. The work could only be performed by a licensed contractor with a special City of Duvall endorsement on their license (which is effectively another fee collected by the city). I also needed to consult a licensed arborist to confirm that tying a rope around the tree would not harm it.
The tree on my side was deemed not large enough to support the rope, so the city suggested installing a pole. But a pole could fall into the road, so I would also need to install cables and safety anchors to permanently support it for public safety. On top of that, I was told I would need a concept design, a safety review, and fully documented engineering calculations, all prepared and signed by a licensed civil or structural engineer in the state of Washington.
This created a new challenge.
I contacted approximately 80 engineers - essentially every structural and civil engineer in King County. Most were not interested. Some said they only design bridges for large public projects and do not take on work below the multi-million-dollar range. Others said they focus on residential design and don't know how to design a bridge.
A few told me that a bridge like this would be difficult to make safe. They pointed out challenges such as wind, snow loads, and heavy rain. One engineer told me I would need to consult the city on proper signage for a proposed 2-inch-wide bridge located 16 feet above the ground, to ensure that people would not attempt to use it. Personally, I doubt that signage would stop someone determined to walk across a rope strung between trees - but what do I know.
Another engineer expressed concern about liability, noting that there are no established municipal codes defining what a "safe" squirrel bridge is. Would squirrels fall off the bridge and file a class-action lawsuit?
A third engineer said such a bridge would require expensive wind tunnel testing of a prototype to address potential vibration issues. Yet another concluded that, due to the absence of standards, the liability alone would make the project unacceptable. Finally, I was told it would cost "multiple thousands" of dollars just for the design - even with a discounted rate for a good cause.
Eventually, I found an engineer who agreed to consult on an hourly basis. I paid the retainer fee, created the design (with some generous help from AI), and submitted the project for review by the City of Duvall.
It took more than a month of negotiation, two rounds of administrative review, and two rounds of engineering review. But eventually, the city ran out of reasons to reject the project and issued me the right-of-way permit (ROW-26-67).
I believe in public safety, and I fully support it. But I am also fairly certain that there is more red tape - more documents, reviews, approvals, and checks and balances - required to build a squirrel bridge in this country than to start a major war in the Middle East. That may sound like a joke, but isn't it the fact.
In the meantime, the world kept moving at a breakneck pace - global events unfolded, oil prices soared - and I received a permit, valid for one year, allowing me to build a rope between two trees.
The squirrel bridge ropes attachment
The squirrel bridge ropes
The permit application with the redacted address.