Bridge 35 was last repainted in 1964. This traditional coating system began to fail in the late 1990s when peeling paint and some corrosion began to appear on the lattice work. The primer and top coat contained approximately 17% lead, so any plan to repaint needed to incorporate a lead abatement plan.  The Museum opted for encapsulation and selected a painted system to achieve this.

The Museum selected Wasser moisture cure urethane bridge coatings.  This system consists of a zinc primer, micaceous iron oxide intermediate coat and a urethane top coat. These coatings can be applied with a relative humidity up to 99% over a wide range of temperatures.

Most of Bridge 35's surfaces were in good shape, and the new coatings effectively encapsulate existing well-adhering lead coatings. So the Museum decided to specify abrasive blasting only where corrosion was present.

The entire steel structure was treated with bleach to kill moss and then cleaned with pressure washers. To assure environmental protection, a system of tarps was erected to catch wash water and any grit from sand blast operations.

Once the timber deck was removed and the structure cleaned, abrasive blasting began.  The grit selected was Cleanblast with Blastox. Blastox is an agent designed to neutralize lead, rendering the waste mixture of grit and paint non-hazardous. Heavy blasting to white metal was performed where corrosion was found.  Other areas were blasted only to remove loose or poorly-adhering coatings.

The entire cleaning and painting operation took just 10 working days, but work was distributed over a five week period because of poor weather.

The new coatings include 3 - 5 mils of MC Zinc primer, 3 - 5 mils of Ferrox B intermediate coating, and 3 - 5 mils of MC Luster semi-gloss top coat.  This painting procedure gives the bridge an appearance very similar to what it had shortly after its 1964 paint application.

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