Serious problems with surface and ground water quality continue to occur in most parts of the US. There are many sources of information that can help you cover these issues.
One starting point is the Spring 2011 newsletter of the National Water Quality Monitoring Council, whose members represent many federal, state, tribal, academic, industry, and other organizations.
In the aftermath of the Gulf of Mexico oil spill, the newsletter highlights nine people who provided updates on various aspects during a February 2011 national meeting. Agencies and institutions represented include NOAA, USGS, EPA, the states of Florida and Mississippi, and the University of Florida and Texas A&M. Topics included research, monitoring, data bases, BP funding, collaborative efforts, and the Gulf dead zone. These nine people and their presentations can provide a starting point for more extensive coverage of these or other Gulf issues.
- Power Point Presentations  of the National Water Quality Monitoring Council from the February 2011 meeting in Pensacola, Florida.
A national wetlands condition assessment that is described as being the first of its kind is being conducted this year by EPA, the US Fish and Wildlife Service, states, and tribes. The results aren’t expected to be published until 2013, but you may be able to glean in-process information by contacting the various players. One element of the project is trial use of a rapid assessment tool, which if proven viable could be used by many others for more extensive and affordable evaluations of wetlands.
One of the many problems faced by the Great Lakes is the influx of degraded or contaminated water from tributary rivers and streams. Some of these problems have been documented in the past; additional monitoring at 30 sites began in February 2011 in order to better identify water quality issues and the specific sources of problems. This monitoring is a subset of the following projects:
- Forecast/Nowcast Great Lakes Nutrient and Sediment Loadings. 
- Determine Baseline and Sources of Toxic Contaminant Loadings. 
- Great Lakes Restoration Initiative, numerous other projects. 
The many tangled threads that influence nitrogen and phosphorous pollution in the RockyMountain region were discussed in a February 2011 meeting attended by 185 people from federal agencies, states, cities, universities, nonprofits, and other organizations. One tangible outcome of the meeting was a set of recommendations to EPA’s Region 8; the people and organizations at the meeting likely will also be good sources for coverage of these issues.
Far from the Rockies, harmful algal blooms (HABs) continue to plague US waters, posing threats to human health and the environment. One of the efforts under way to better understand human health impacts is being coordinated through CDC’s Harmful Algal Bloom-related Illness Surveillance System. Ten states are participating (FL, IA, MA, MD, NY, OR, SC, VA, WA, and WI).
A starting point for NOAA’s ongoing efforts to monitor and forecast HABs and determine causes and effects is:
One of the pathways through which HABs can affect human health is drinking water contamination. USGS has found that, in some instances, two basic indicators of such contamination are taste and odor. EPA can use this information as it works to determine whether various HAB contaminants should be among the required substances to test for in drinking water.
- Algal Blooms Consistently Produce Complex Mixtures of Cyanotoxins and Co-Occur with Taste-and-Odor Causing Compounds in 23 Midwestern Lakes. 
The newsletter also has news for numerous states. Among the highlights:
In California, the legislature has mandated a more comprehensive water monitoring effort. That is still a work in progress; you can see some of the latest developments in a 10-year plan released December 29, 2010.
The links between environmental justice and water quality were the theme for a Maryland conference held Nov. 18, 2010.
- 2010 Annual Conference, November 18, 2010, "Environmental Justice: Healthy Waters, Healthy Communities." 
In Utah, coordinated water monitoring is still a work in progress as the Utah Monitoring Council segues into its second year of existence.
The West Virginia Water Research Institute continues to monitor water quality at 16 locations in the Monongahela River basin, in order to track possible impacts from coal mining, gas drilling, and other pollution sources. In related efforts, many volunteer organizations have been doing their own monitoring and research, and pushing for solutions to identified problems.
Several other water quality issues are covered in the newsletter; check it out to see if they are related to issues you cover, and to get more details on the information provided above.
There are many other starting points for covering surface and ground water quality issues. Examples include:
- EPA, Our Waters  (includes links to lakes, rivers and streams, oceans, watersheds, wetlands, and “where you live”).
- USGS, Water Quality Information. 
- USDA, National Water Management Center. 
- US Fish and Wildlife Service: Wetlands ; Fisheries and Habitat Conservation. 
- Association of State & Interstate Water Pollution Control Administrators. 
- Environmental Council of the States, Water. 
- Western States Water Council. 
- Association of State Wetland Managers. 
- Clean Water Action. 
You might also check with your state’s departments of natural resources and/or environment.