Some ecological implications on clearing streams

In my blog entry of Aug, 22, More on debris in creeks, I reported on a recent conversation that I had on the issue with a friend of mine who is an environmental scientist. She read my blog and sent me a reply where she offered some further insights on the issue debris in streams including the effect clearing streams has on the larger ecosystem surrounding the stream. I learned a lot from her e-mail, which helped to fill some "holes" in my thinking. She gave me her permission to reproduce her response in my blog. I hope that the title of this entry, some ecological implications on clearing streams, correctly summarizes her response.

She says:

I took a look at your "ramblings" - interesting comments. I think I should clarify something we talked about that I didn't state well, about the debris that holds water. You have to think about the entire stream, even to what it flows into, when you think about debris. You also have to think about local conditions vs. what's happening farther away.

Let's start with local conditions. Say you have a stream in your backyard. Any rain that comes down too fast for the ground and vegetation and debris around the stream to absorb will run off into the stream. If you take out the "debris", it will run off faster. If there's enough water, it may even run off fast enough to remove vegetation. Certainly if you have bare soil, some of the bare soil will run off with the water. Vegetation and debris help hold the soil in place (vegetation is more effective at that), but some soil is likely to wash away in any case when there's a lot of water. If your house is right next to the stream, you may consider that faster runoff a good thing, but too much of it can take the soil away from your foundation. It's not considered very smart to build a house right next to a stream (in the stream's floodplain), and most places require buffer zones between construction and streams now. If your house is not right next to the stream, then, as the stream rises, the buffer zone with all the vegetation and debris will help hold the water away from your house. Debris also provides essential habitat for some wildlife: think of chipmunks living in fallen tree trunks near streams, and crayfish and other aquatic invertebrates (some that trout like to eat) finding shelter among debris in the streams.

OK, what about not-so-local conditions? Say you're pretty far upstream and you clear out your debris to get faster runoff or maybe just to make your lawn "prettier", and all your neighbors do the same. Then, when it rains more than the ground can absorb, all that water goes downstream, with its inevitable load of soil and whatever pollutants also ran off. So there is lots more water downstream, and those downstream neighbors get more flooded than they would have if you hadn't cleared out the upstream. (For example, Route 17 in Hackensack and Lyndhurst floods when it rains a lot in Mahwah in northern NJ.) In the meantime, because there's more water coming into the river, it's inevitably getting more soil, pollutants, and other stuff washing into the river. That means that the river in general is getting shallower and more prone to flooding. It's also getting more polluted (and so is the bay that the river goes into). Buffer zones of wetlands along a river provide conditions that break down pollutants and keep surface waters cleaner.

Debris is such a pejorative word. It sounds like "garbage" or "trash". Our society favors flat green monocultures, often of species that aren't native to the area. People remove trees and shrubs because of the "untidyness" of dropped leaves and limbs and seeds. We remove water and spray poisons to get rid of mosquitoes and other insects, even though those insects serves as food for other species. It's no wonder we're having a biodiversity crisis.

Thoughts on flood mitigation

I should be clear that while I have been following the aftermath of the recent floods in local media and various websites, and live not all that far from the Delaware River, I am not a resident of one of the river towns. Nor have I attended any meetings where residents of river towns may express their views on either Corzine's flood mitigation strategies or the final draft of the Delaware River Flood Mitigation Task Force.

The question that I have been thinking about is what do the residents of the river towns (those towns on the Delaware River) think of these two sets of strategies? I don't have an answer for this. If there happens to be anyone reading this blog who lives in any river town affected by the floods who would care to comment, I'd love to hear from you. Of course, I don't want to leave anyone out, I'd like to hear from you, no matter where you live, regarding any thoughts you might have on these flood mitigation strategies or the strategies of adjoining states.

Governor Corzine Announces New Flood Control Rules

I found this press release from NJ Governor Corzine on the on the NJ State website Governor's press release page on the NJ State Government site.

In today's Star Ledger, Steve Chambers and Jeff Whelan (Wed. Aug. 22 2006, Hunterdon and Somerset edition, section 2, pp. 13, 17) report that:

"Regulations to implement the proposal could be introduced as early as today and could be enacted after a public comment period without legislative approval."

The article may be found here for the next fourteen days (through Tuesday, Sept. 5, 2006).

Aug-22-06 Governor Corzine Announces New Flood Control Rules

FOR MORE INFORMATION:
Anthony Coley
Brendan Gilfillan
609-777-2600

GOVERNOR CORZINE ANNOUNCES NEW FLOOD CONTROL RULES

TRENTON- Governor Jon S. Corzine today announced significant changes to the rules of the Flood Hazard Area Control Act, as recommended by New Jersey’s Flood Mitigation Task Force report. He also announced that the state will pay the local communities’ share of FEMA’s costs associated with the July 2006 floods.

“We won’t ever stop floods from happening but we can mitigate their impact,” Governor Corzine said. “By implementing a number of new regulations, preventing development in flood-prone areas and improving drainage all along the Delaware Valley, we’re taking steps that provide both immediate and long-term impact.”

The new rules will clarify and reorganize New Jersey’s regulations to limit new development in flood plains. Current buffer zones of 25 to 50 feet will increase to 50, 150 or 300 feet depending on the category of the waterway. To provide additional buffer protection the administration will support the inclusion of funding within the Garden State Preservation Trust (GSPT) for the purchase of low-lying properties, known as Blue Acres, which are prone to flooding.

“We believe these are substantive recommendations for averting destruction of property and for protecting lives in communities repeatedly ravaged by flooding,” said Department of Environmental Protection (DEP) Commissioner Lisa P. Jackson. “The regulations being proposed today are among the nation's strongest for providing stream-corridor protections and for imposing limitations on development in a flood plain.”

Environmentally responsible stream cleanings and the relocation and reconstruction of damaged buildings will be streamlined through increased access to general permits. Additionally, new permits-by-rule will give property owners authorization to undertake specific regulated activities without the need to obtain prior written approval from the DEP. This will streamline activities as complicated as using machinery to remove major obstructions from waterways or elevating buildings above flood hazard areas, as well as activities as simple as building a fence or a patio.

Adding fill, which includes construction material, buildings and roads, to a flood plain can make a river more prone to flooding. Current development rules require that if any fill is added to a flood plain, an 80% equivalent of that fill must also be removed from the same plain.

New rules will increase the requirement to 100% resulting in what is called 0% net fill.

Additionally, New Jersey is working with FEMA to modernize and digitize flood plain maps. This will result in more accurate maps that can be easily updated and used to more reliably predict future flooding.

Finally, steps are being taken to address several immediate local problem spots. The Department of Transportation (DOT) will evaluate possible drainage improvements along the Route 29 corridor. The DEP and the Natural Resource Conservation Service are currently exploring preventative measures to keep Swan Creek from backing up into Lambertville. The New Jersey Water Supply Authority has also hired an engineering firm to address breach concerns in the Stockton Canal, and is also clearing debris to improve drainage and make repairs all along the Delaware Canal.

NJ Flood Mitigation Task Force Report

After I wrote last night, that I nothing more to say about the recent floods, I read about the final report of the Delaware River Flood Mitigation Task Force in this morning's Star Ledger. After the September 2004 and April 2005 floods, Acting Governor Codey created the Delaware River Flood Mitigation Task Force (DRFMTF). Their final report was released on Tuesday, August 22 and is available in its entirety here. Note that you will need Adobe Reader to read the file.

I did found this paragraph from the report's executive summary (New Jersey Flood Mitigation Task Force 2006, p. 2) to be a concise summary of the issues of concern:

"The Task Force has found that damage during these events was disproportionately attributable to patterns of development that are insensitive to flooding and the lack of adequate hazard mitigation planning. The Task Force further found that recovery in the aftermath of the floods was hampered by inconsistent approaches by government agencies, uncertainty and gaps in relevant rules and regulations; and regulatory and bureaucratic barriers to appropriate reconstruction. In view of continued development pressures and expected continued increases in hurricane activity over the next several decades, significant changes in policy, management, planning, and development will be needed to limit New Jersey's risk of loss from future flood events in the Delaware basin. New Jersey is the state with the fourth largest number of repetitive loss properties and fourth largest in the total amount of National Flood Insurance Program (NFIP) payouts."

The NJFMTF then makes a series of recommendations (I counted 23) that are summarized after the executive summary in about three pages. These recommendations are grouped into the following categories (each with a number of recommendations):

1. Regulatory protection of flood plains and homes must be strengthened.
2. Mitigation and Control Measures should be pursued.
3. Planning and additional resources are needed to reduce flood risk.
4. Homeowners need focused assistance before and after flooding.

It will be interesting, to say the least, to see how many of these recommendations are implemented and/or modified over the coming months as they wend there way through New Jersey's legislative or gubernatorial processes over the coming months.

More on debris in creeks

While we were on our most recent hiatus I had the chance to talk about the most recent flooding on the Delaware River with an environmental scientist. I learned some thing about debris in stream and creek tributaries of rivers. Since I wondered about local media reports of the flooding of creek–tributaries of the Delaware River and the River itself in late June and the concern that debris in these creeks may have contributed to the flooding, I am writing about what I learned from my friend.

I took an opportunity to steer our conversation to the issue of debris in the creek–tributaries of the Delaware because I was curious about what she would say. She told me that leaf litter absorbs water. Thinking about the sometimes pain in the you know what that wet leaves can be, this made a lot of sense. Who among us hasn’t slipped on wet leaves at one time or the other?

I recall that a fair amount of the debris that I spotted a few weeks ago and wrote about in earlier entries was leaf litter. Much of the rest was tree branches and or tree trunks of varying sizes. My friend pointed out that trees as well as leaves absorb water. The stated implications of our conversation being that leaf litter and tree branches and/or trunks in creeks may actually help reduce the flooding problem as opposed to contributing to flooding of these creeks and tributaries.

Of course, all this is academic when you consider that neither of us had seen the affected creeks in the days leading up to the most recent floods or in the days immediately after the flood receded. Perhaps the debris in the creeks did create enough of a “damming effect” to force the creek waters to rise and flood earlier then they would have other wise. I also recall that in July 6, 2006 article, the Hunterdon Democrat reported that pipe leading to the Delaware in the vicinity of the Swan Creek –– one of the tributaries of the Delaware –– was clogged with debris, leading to flooding in the area of the Swan Creek. The article did not report on the nature of the debris.

I did learn something from my friend. However, I find myself left with a lot of unanswered questions. At this point, I don’t think that I have any easy answers. When and if I come upon information that may shed light on the issues that I have raised, I will offer them here. Or, if any of you have any experiences or insights, please share them in the comments section

In the meantime, my curiosity is now sufficiently aroused that I may want to take the time to walk along some of the creek–tributaries in Lambertville and the other River towns to see how much debris is still left in these tributaries and the nature of the debris.

Update on Lambertville-New Hope Bridge

On July 6, 2006, The Hunterdon Democrat reported on an engineer’s inspection of the Lambertville–New Hope bridge. The lowest visible portion of the bridge deck of the Lambertville–New Hope Bridge suffered some minor damage in the form of “slight denting.” None of the piers were damaged. The bridge passed weight–bearing load tests. Repairs will be necessary, and the Hunterdon Democrat is reporting that the engineers are saying that bridge is safe for vehicular traffic.

The assumption being that this was the result of damage from floating debris. This bridge, like the other crossings, were inspected prior to reopening to be sure that both the bridge and the roads were safe to reopen. The Hunterdon Democrat did make two interesting points in regards to the Lambertville–New Hope Bridge. One is that Emergency responders are encouraged to use the toll bridge (a couple of miles north) when possible. The second point is that guards are on duty 24 hours a day to enforce weight limits.

This bridge is known by locals as “the free bridge” when compared to the toll bridge where U.S. Highway 202 crosses the Delaware River about two miles north of the free bridge. For those of you who are not familiar with these two rivertowns, the free bridge connects the shopping/restaurant districts of Lambertville, NJ and New Hope, PA. Any longer–term closing of the free bridge has the potential to severely impact businesses in both towns.

I was interested in the fact the Hunterdon Democrat made a point of saying that guards are on duty 24 hours to enforce weight limits. Is this the normal course of operations for the bridge? I can only hope so. Weight limits should be enforced at all times, not just after a flood when the bridge sustained some minor damage.

I am sure that the Hunterdon Democrat will report on the status of these repairs if they are deemed newsworthy. This should be easy for me to do because I get the Hunterdon Democrat delivered to my home. I will monitor the local press over the coming weeks and months and report back here if anything interesting happens.

awesome videos of floods in Frenchtown NJ

Frenchtown is about ten miles north of Lambertville NJ on the Delaware. In one of my earlier posts, I posted a link to some photos posted on the website of Emergency Management Services of Hunterdon County. For those of you who haven't visited this site in the past couple of weeks, I urge you to go back to the Hunterdon County EMS site to see some really awesome videos taken by Donna and Bill Knispel of Frenchtown NJ.

Speaking of debris, this video clip taken by the Knispels shows a rather large tree floating down the River.

I was able to view these video clips on my Mac with Quicktime. I don't know what you PC folk use to see videos on the web. I'd imagine that one of your windows programs will do fine.

Another picture of floods in Lambertville NJ

At the time that I made my entry, floods part 3 on July 7, on the Delaware River floods of June 29, I was not able to find a picture of the parking lot at the Lambertville Station in Lambertville where I took my photographs. I thought that it might be interesting to post a link to a picture. Well, I finally was able to spend some time on the website of the Delaware River Basin Commission (DRBC) . They have a webpage with links to variety of information on the June 2006 floods . I have downloaded some documents from that website that I am in the process of reading. When I am finished reading these documents, I will post my thoughts and impressions here.

When I got to the DRBC June 2006 flood page, I scrolled down to the link for photographs and found this photograph . Note that the floodwaters go almost up to the top of the arches on the “first floor” of the inn at Lambertville Station. Pretty impressive. The place where I was standing to take the photographs of the Lambertville-New Hope Bridge was probably in about eight feet of water. At least this is my guesstimate.

Speaking of the bridge, I read in one of the local papers recently that there was a possibility that there was some damage from debris to the bridge in the River. I have to say that having seen the river a day after both the June 2006 floods and the April 2005 floods, that I saw some pretty impressive trees floating in the River. Really big trees. So, I am not surprised about the possibility of damage to the bridge. This to is something that I want to follow-up on and will write about here. Speaking of debris, apparently one of the issues that the folk in the towns along the River (and others) is the issue of debris in the creeks that flow into the River. There is a creek a couple of blocks south of the Lambertville Station called the Swan Creek. The Swan Creek flooded, and if there is any debris in the creek from either the Sept. 2004 or the April 2005 floods, then I can only imagine that this could of made the Swan Creek flooding worse.

We went for a walk this past Sunday, about 2 miles north on the canal that is about one city block in from the River. We passed two places where there were bridge abutments, sorry no pictures yet (to be honest, I was so hot, I couldn’t deal with standing in the sun to take pictures). The first was when an old railroad crossed the canal on elevated track. The second was another bridge where some sort of creek with a small waterfall met the canal. At both bridges, I saw a large amount of what I call tree litter, branches of various sizes. When it cools down a little, I am going to go back and take some pictures. Again, stay tuned.



In closing, one picture I did take last Sunday was a picture of the Lambertville-New Hope Bridge. This picture shows the River at more or less “normal” level. If you look closely, you will see a little bit of dirt around the bridge abutments. If you go back to my July 7 entry, you won't see any dirt around the bridge abutments.