The Treaty Rights at Risk report highlights an alarming trend in western Washington. If we don’t change the way we make room for our increasing population, things are only going to get worse for salmon. For example, based on the number of people we expect to live here in the future, here is how the amount of impervious surface (roads, parking lots, roofs) will change in the future:
Here’s a part of the report explaining a bit more:
In a recent geographic information system (GIS) analysis of Puget Sound land cover data and population growth rates, existing and projected trends demonstrate dramatic increases in the conversion of vegetated areas to concrete. These increases in impervious surfaces impact salmon habitat by removing essential vegetation and biota, increasing runoff, conveying pollutants, and altering hydrology. Without appropriate planning, placement, and mitigation, these actions will continue to imperil salmon.
You can find out how the map was developed here (footnote 13).
The report also outlines some other startling examples:
- Within the Stillaguamish watershed, during the time period of 1996 through 2006, there was a decrease of 41 percent in forest cover within the Urban Growth Area and a 22 percent decrease of forest cover inside rural residential areas. Now, only 23 percent of the 1,777 acres of riparian area within the floodplain have any forest cover.
- In the Hoh watershed, approximately 31 percent of private forestlands were harvested between 1998-2010 (post ESA listing).
- In the Snohomish watershed, dikes, levees, and flow devices have resulted in the loss of 55 percent of critical mainstem salmon habitat.
- In the Port Gamble S’Klallam Tribe’s usual and accustomed grounds, places such as Port Gamble Bay have had 74 percent of the shoreline armored or modified.
- In the Skokomish basin, the watershed has experienced a 51 percent increase in impervious surfaces, with a third of that paving occurring just one mile from Hood Canal.
- In the Muckleshoot Indian Tribe’s area of concern, NOAA models predict that more than half of the stream miles of known coho salmon habitat will experience pre-spawn mortality rates greater than the average, and that 141 of those miles will experience mortality rates greater than 35 percent, when under normal conditions these rates are generally less than 1 percent.