Last month, the American Society of Civil Engineers issued its Report Card for America’s Infrastructure, which it does every four years. The cumulative grade-point average, across 16 infrastructure categories is D+. This actually represents an improvement from 2009.

The GPA has languished in the D range since 1998 because we haven’t maintained or invested enough money in these systems. If you thought your tax dollars were being wasted on federal stimulus projects, you should know the grade four years ago was a D.

ASCE credits short-term boosts in federal funding with improvements in several categories. In fact, none of the 16 categories experienced a lower grade than it did in 2009.

Here are the categories that most closely align with the piping and plumbing industry:

Drinking water: Despite an estimated 240,000 water main breaks annually, the grade in this category actually went up to a D from D- in 2009. With many pipes more than 100 years old, the cost to replace them all could exceed $1 trillion in the decades ahead, according to the American Water Works Association.

Ironically, the urgency to replace these pipes would be greater if the quality of U.S. drinking water were not as high as it is. In large part thanks to the plumbing industry, outbreaks of disease linked to drinking water are rare.

Wastewater:The grade in this category also improved to a D from a D- in 2009. Pipes represent the largest capital need, making up $223.5 billion of the $298 billion needed for the nation’s wastewater and stormwater systems over the next 20 years. Fixing and expanding the pipes will address sanitary sewer overflows, combined sewer overflows and other pipe-related issues. Capital needs for treatment plants comprise from 15% to 20% of total needs, but the percentage probably will increase due to new regulatory requirements.

Schools: Another D appears in this category, the same grade as in 2009. We need to invest at least $270 billion to modernize and maintain our schools. Public school enrollment is projected to gradually increase through 2019, yet state and local school construction funding continues to decline. National spending on school construction declined last year to $10 billion, which is half the level spent before the recession.

Energy: The grade for energy remains a D+, where it was four years ago. The availability of energy in the form of electricity, natural gas and oil will become a greater challenge after 2020 as the population increases. Many of the country’s 150,000 miles of crude oil and product pipelines and 1.5 million miles of natural gas transmission and distribution pipelines are located underground and cross multiple states. New federal safety requirements were enacted in 2011 to address the increased number of pipeline failures and other incidents due to aging infrastructure and lack of maintenance.

ASCE says its Report Card demonstrates that we can improve the nation’s infrastructure when we invest in it. That, of course, is easier said than done in this era of sequestration and federal budget deficits.

 Nevertheless, you can make a direct tie between a country’s infrastructure and economic health. The still-deplorable grades in ASCE’s Report Card show how much work remains to be done. If you look on the bright side, you’ll see the business opportunities that could be waiting for you if the country gives our infrastructure the priority it deserves.